TECHNICAL PROGRAM

Materials Science

& Technology

2008 Conference

& Exhibition

October 5-9, 2008

David L. Lawrence Convention Center

Pittsburgh, Pennsylvania

ABSTRACT BOOK

MS&T’08 • October 5-9, 2008 • Pittsburgh, Pennsylvania

About the Organizations Behind MS&T’08

The American Ceramic Society serves the informational, educational and professional needs of the global ceramics community. The Society’s more than 6,000 members comprise a wide variety of individuals and interest groups that include engineers, scientists, researchers, manufacturers, plant personnel, educators, students, marketing and sales professionals, and others in related materials disciplines. Our members are pioneering today’s research and information in fast growing ceramic fields such as nanotechnology, biomedicine, nuclear, armor and electronics, providing a platform for valuable research and discussion that will help build the future of ceramic materials. ACerS provides members in 80 countries with access to top ranked periodicals, books, meetings and online technical information. For more details, visit www.ceramics.org or contact Megan Mahan, director of membership and marketing, at (614) 794-5894.

Association for Iron & Steel Technology was established on January 1, 2004, by the merger of two longstanding societies, the Association of Iron and Steel Engineers (AISE) and the Iron & Steel Society (ISS). The goal of the association is to advance the technical development, production, processing and application of iron and steel. The best practices of both predecessor organizations were incorporated into AIST, and we now have a strong, international, member-based technical organization that can sustain itself in an environment of continual change. AIST is committed to presenting superior technical meetings, conferences, exhibits and publications to better serve those involved in the iron and steel community, including steel manufacturers, suppliers, consumers and academics. To learn more, visit www.aist.org.

ASM International is the worldwide society for materials engineers and scientists. Dedicated to advancing industry, technology and applications of metals and materials, ASM benefits the materials community by providing scientific, engineering and technical knowledge, education, networking, and professional development. The core values of ASM are: to provide exceptional member/customer service and input; to assure stewardship and integrity of materials information; to deliver the benefits of a diverse worldwide community of volunteers; to pursue continuous improvements and an adaptive, responsive and flexible organization; and to advance the importance of education, experience and lifelong learning. Learn more about ASM International’s global strategies, services, and member benefits. Visit www.asminternational.org.

The Minerals, Metals & Materials Society is the professional organization encompassing the entire range of materials science and engineering, from minerals processing and primary metals production to basic research and the advanced applications of materials. The Society’s broad technical focus covers light metals; electronic, magnetic and photonic materials; extraction and processing; structural materials; and materials processing and manufacturing. Included among TMS professional members are metallurgical and materials engineers, scientists, researchers, educators and administrators who work in industry, government and academia, as well as students. They hail from more than 70 countries on six continents. The mission of TMS is to promote the global science and engineering professions concerned with minerals, metals and materials. The Society works to accomplish its mission by providing technical learning and networking opportunities through interdisciplinary and specialty meetings; continuing education; publications, including four journals and proceedings; and its Web sites. To learn more, visit www.tms.org or www.materialstechnology.org.

Introduction

This volume contains abstracts for more than 1,750 papers to be presented duringthe Materials Science & Technology 2008 Conference and Exhibition (MS&T’08) inPittsburgh, Pennsylvania. The abstracts are reproduced as submitted by authors, aformat that provides for longer, more detailed descriptions of papers. MS&T’08accepts no responsibility for the content or quality of the abstract content.Abstracts are arranged by symposium then session title. An Author Index appearsat the back of this book. The Meeting Guide contains locations of sessions withtimes, titles and authors of papers, but not presentation abstracts.

How to Use the Abstract Book

Refer to the Table of Contents to determine page numbers on which specificsession abstracts begin. At the beginning of each session are headings that listsession title, location and session chair. Starting times for presentations precedeeach paper title. The Author Index lists each presenting author and the pagenumber on which their abstract can be found.

000.MST_Abs_IFC 9/3/08 3:01 PM Page 2

Table of Contents

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvaniaii

KEYNOTE & LECTURESFrontiers of Science and Society: Rustum Roy Lecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1Opening Session and Keynote Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32ASM/TMS Distinguished Lecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Alpha Sigma Mu Lecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Richard M. Fulrath Award Lectures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Arthur L. Friedberg Memorial Lecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90TMS Young Leaders Tutorial Luncheon and Lecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90Edward DeMille Campbell Memorial Lecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90Edward Orton Jr. Memorial Lecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91Robert B. Sosman Lecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .198

SPECIAL TOPICSACerS 110th Anniversary Symposium

ACerS 110th Anniversary Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Emerging Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54

Education and Professional DevelopmentEducation Trends and Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Professional Development/Industrial Perspective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54Undergraduate Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55

Industry Track 2008Industry Track 2008,Tuesday PM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135Industry Track 2008, Wednesday AM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Industry Track 2008, Wednesday PM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199

Perspectives from Emerging Materials Professionals: Early Strategies for Career DevelopmentKey Strategies for Career Development I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Key Strategies for Career Development II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199

SBIR Program; Development of Innovative Materials Technologies for Military SystemsDevelopment of Innovative Materials Technologies for Military Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135

The National Materials Advisory Board Dissemination Series (by invitation only)National Materials Advisory Board Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161

ELECTRONIC & MAGNETIC MATERIALSCopper and Copper Based Alloys in the Electronics Industry

Copper and Copper Based Alloys in the Electronics Industry I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Copper and Copper Based Alloys in the Electronics Industry II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56

Electroceramic Technologies: The Past and Future; ACerS Electronics Division 50th AnniversaryElectroceramic Technologies: Processing Advances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91Electroceramic Technologies: Advances in Ferroelectrics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92Electroceramic Technologies: Advances in Dielectric and Magnetoelectric Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Electroceramic Technologies: Microwave Dielectrics and Sensor Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136

Fabrication, Microstructures and Interfacial Properties of Multifunctional Oxide Thin Films Processing and Applications of Oxide Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Preparation and Properties of Oxide Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Microstructures, Defects, and Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227Fabrication Issues of Oxide Thin Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Microstructure and Dielectric Properties of Oxide Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .260

Ferroelectrics and MultiferroicsPiezoelectric Ceramics and Thin Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Domain Switching, Phase Transition Behavior,Texturing, and Lead-free Piezoelectrics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57

i-viii.MST_Abs.TOC.1st 9/3/08 3:03 PM Page ii

Epitaxial and Oriented Films, Materials Integration, Strain-induced Phenomena . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93Multiferroics and Magnetoelectric Composites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137Physical Properties and Nanoscale Phenomena in Ferroelectric, Ferromagnetic,

and Magnetoelectric Thin Films and Nanostructures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Single Crystals/Relaxors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200Physical Properties and Nanoscale Phenomena . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .229Piezoelectric Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261

Interfaces and Defects in Functional OxidesCharacterization of Functional Oxides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138Functional Oxides:Thin Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164

International Symposium on Advanced Dielectric Materials & Electronic DevicesComposition, Processing, Microstructure, and Property Relationships I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Composition, Processsing, Microstructure, and Property Relationships II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Composition, Processing, Microstructure, and Property Relationships III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94Synthesis and Properties I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139Advancement in Dielectric Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Synthesis and Properties of Thick and Thin Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Design, Preparation, and Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201

Low Temperature Processing for Integration of Microelectronics DevicesPiezoelectric Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202Direct Write Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Advanced System Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261

Pb-Free, Pb-Bearing Joining and Packaging Materials and Processes for MicroelectronicsMechanical Properties and Service Reliability of Solders and Solder Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Materials and Processes for Advanced Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Microstructural Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96

Perovskite Oxides: Films, Nanostructures, Properties, and ApplicationsPerovskite Oxide Films and Nanostructures I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Perovskite Oxide Films and Nanostructures II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Oxide Films and Nanostructures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92Physical Properties of Perovskite Oxides I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Physical Properties of Perovskite Oxides II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203Heterostructured Perovskite Oxides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Perovskite Oxides - Superconducting Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262

ENVIRONMENTAL & ENERGY ISSUESCeramics and Glass for Waste Minimization, Stabilization, and Disposition

Materials for Nuclear Applications and Environmental Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Low Temperature Waste Form Development and Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Waste Glass Leach Testing and Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Vitrification Technology Development and Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Waste Glass Chemistry and Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167

Energy MaterialsBatteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Characterization Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Energy Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Other Energy Materials I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Other Energy Materials II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Nuclear Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Other Energy Materials III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Thermoelectric Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169

Frontiers in Materials Science: Closing the Nuclear Fuel CycleAdvanced Nuclear Fuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203Nuclear Fuel Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231

www.matscitech.org iii

i-viii.MST_Abs.TOC.1st 9/3/08 3:03 PM Page iii

Fuel Cells: Materials, Processing, Manufacturing, Balance of Plant and Systems OperationFundamental Electrochemical Processes: Electrode Chemistry, Kinetics, and Degradation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Novel Fuel Cell Systems: Materials, Operation and Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Cell and Stack Component Materials I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Cell and Stack Component Materials II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Corrosion, Degradation and Protection Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Manufacturing, Balance of Plant, Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232

Green Technologies for Materials Manufacturing and ProcessingEnvironmentally Benign Process I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .171Environmentally Benign Process II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Green Technology Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .234Waste Minimization and Recycling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263

Materials and the Climate Change ChallengeMaterials and the Climate Change Challenge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235

Nanoscale Design of Materials for Extreme Radiation EnvironmentsFundamentals of Nanoscale Design for Radiation Damage Tolerance I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Fundamentals of Nanoscale Design for Radiation Damage Tolerance II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Irradiation Studies in Nanomaterials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101

Thermoelectric Materials: Science, Technology and ApplicationsThermoelectric Technology and Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65Nanoengineered and Oxide Thermoelectric Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Oxide Thermoelectric Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Thermoelectric Antimonides,Tellurides, and Borides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172Thermoelectric Materials Properties and Characterizations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .206

FUNDAMENTALS & CHARACTERIZATIONACerS Sosman Award Symposium: Kinetic Engineering of Interfacial Transport Processes

Robert B. Sosman Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173

Ceramic Surfaces, Grain Boundaries and InterfacesInterface Thermodynamics and Segregation/Adsorption I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39Interface Thermodynamics and Segregation/Adsorption II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Interface Structure and Properties I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Self Organization and Biomineralization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Thermodynamics, Kinetics and Atomistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236Interface Structure and Properties II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264

Discovery and Optimization of Materials through Computational DesignThermodynamic and Kinetic Processes for Materials Optimization I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39Thermodynamic and Kinetic Processes for Materials Optimization II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Ab Initio Approaches for Hydrogen Storage Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Multiscale Materials Design I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Multiscale Materials Design II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1743D Modeling and Design of Microstructures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208Mesoscale Modeling and Microstructural Evolution I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .237Mesoscale Modeling and Microstructural Evolution II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265

Failure Analysis for Problem SolvingJoining, Welding and Brazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Litigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Fatigue and Fracture I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Fatigue and Fracture II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Tools and Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Historical Case Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Modeling and Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238

Fatigue of Materials: Competing Failure Modes and Variability in Fatigue LifeCrack Initiations and Variability I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvaniaiv

i-viii.MST_Abs.TOC.1st 9/3/08 3:03 PM Page iv

Crack Initiations and Variability II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Very/Ultra High Cycle Fatigue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106Fatigue Variability/Statistical Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Fatigue of Steels, Nickel and Titanium Alloys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .176Fatigue of Advanced Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .210Modeling, Statistics, Life Prediction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .239

International Symposium on Defects, Transport and Related PhenomenaDefects and Transport Related to Fuel Cells and Batteries I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Defects and Transport Related to Fuel Cells and Batteries II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70Defects and Transport Related to Fuel Cells and Batteries III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107Defects and Transport in Ceramics I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .147Defects and Transport in Ceramics II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Defects and Transport in Ceramics III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211Defects and Transport in Ceramics IV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241

Lifecycle of Engineered Residual Stresses: Processing, Aging, and RejuvenationLifecycle of Engineered Residual Stresses: Processing, Aging, and Rejuvenation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242

Micro- and Nano- Mechanical Behavior of Low-Dimensional Structures and MaterialsMicro- and Nano- Mechanical Behavior of Materials - Metallic Materials I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Micro- and Nano- Mechanical Behavior of Materials - Metallic Materials II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Micro- and Nano- Mechanical Behavior of Materials - Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .147Micro- and Nano- Mechanical Behavior of Materials – Ceramics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .178Micro- and Nano- Mechanical Behavior of Materials - Soft Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211

Modeling of Multi-Scale Phenomena in Materials ProcessingStress Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42Microstructure Evolution I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42Solution Algorithms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Microstructure Evolution II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Microstructure Evolution III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110Multiple Length-scale Coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Microstructure Evolution IV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .148

Performance and Growth of Bulk and Thin Film Materials - Role of Surface and Interface PhenomenaRecent Advances in Growth of Thin Film Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .180Recent Advances in Growth of Inorganic and Organic Thin Film Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Microstructures and Properties of Thin Films in the Sub-Micron Range and Beyond . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Role of Surfaces and Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .266

Phase Stability, Diffusion Kinetics & Their Applications (PSDK-III)Microstructural Analysis, Control and Modeling I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Diffusion Kinetics I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Microstructural Analysis, Control and Modeling II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Diffusion Kinetics II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .149Diffusion Kinetics III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .181Thermodynamics and Phase Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214Microstructural Analysis, Control and Modeling III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .245

Phase Transformations & Microstructural Changes during Sustained Mechanical ForcingModeling and Simulation Approaches for Driven Transformations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113Deformation-induced Microstructural Changes and Phase Transformations I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Deformation-induced Microstructural Changes and Phase Transformations II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182

Recent Advances in Structural Characterization of MaterialsX-Ray and Neutron Diffraction: Developments and Applications I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43X-Ray and Neutron Diffraction: Developments and Applications II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74X-Ray and Neutron Diffraction: Developments and Applications III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Spectroscopic Techniques: Developments and Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115Structural Characterization of Materials: Panel Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150New Techniques and Multidimensional Approaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .183Electron Microscopy and Electron Diffraction: Developments and Applications I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .215

www.matscitech.org v

i-viii.MST_Abs.TOC.1st 9/3/08 3:03 PM Page v

Electron Microscopy and Electron Diffraction: Developments and Applications II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Electron Microscopy and Electron Diffraction: Developments and Applications III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .267

Structure-Property Relationships in Multi-Functional MaterialsStructure-Property Relationships in Multi-Functional Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247

The Effect of Electrical Fields & Stress on Diffusional Transport in Ceramics & Related PhenomenaInterface Kinetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Li+ Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Enhanced Sintering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .217

IRON & STEELAdvancements in Steel Production through EAF, Ladle Refining, and Continuous Casting Technologies and Practices

Advancements in Steel Production: EAF, Ladle Refining, and Continuous Casting Technologies and Practices . . . . . . . . . . . . . . . . . . . . . . . .249

International Symposium on Materials Engineering for Structural ApplicationsThermo-Mechanical Control Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Thermal Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150

New Developments in Processing and Properties of Zinc-Coated Sheet SteelsNew Developments in Processing and Properties of Zinc-Coated Sheet Steels I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44New Developments in Processing and Properties of Zinc-Coated Sheet Steels II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76

Recent Developments in Steel ProcessingSurface Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45Heat Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117

Refractory Innovations and Novel Applications in Iron & Steel ManufactureRefractories for Iron and Steel I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Refractories for Iron and Steel II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .217

Steel Product Metallurgy and ApplicationsPress-Hardening of Steels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Multiphase Microstructural Process Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Microstructure - Property Correlations I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Microstructure - Property Correlations II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Material Testing and Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Microstructure - Property Correlations III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218Property - Application Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250Microstructure Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .267

MATERIALS & SYSTEMSAdvances in Biomedical and Biomimetic Materials

Biomimetic Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Scaffolds for Tissue Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79Metallic Implant Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Advanced Biomaterials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .152Surface Modification of Biomaterials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188Bioceramics I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Nanoparticles for Medical Diagnosis and Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Bioceramics II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .252Bioceramics III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268

Advances in Characterization and Modeling of Cementitious MaterialsAdvances in Modeling the Behavior of Cement-based Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48New Developments Regarding Experimental Techniques for Characterizing Cement-based Materials I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81New Developments Regarding Experimental Techniques for Characterizing Cement-based Materials II . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121Modified Fresh or Hardened Properties and Nontraditional Applications of Cement-based Materials I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Modified Fresh or Hardened Properties and Nontraditional Applications of Cement-based Materials II . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153ACerS Cements Division Della Roy Lecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvaniavi

i-viii.MST_Abs.TOC.1st 9/3/08 3:03 PM Page vi

Amorphous Materials: Common Issues within Science and TechnologyPolymers and Related Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Metallic Glasses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154

Enabling Surface Coating Systems: Science and TechnologyThermal Barrier Coatings I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Thermal Barrier Coatings II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .155Environmental Barrier Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Tribology Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Advanced Processing and Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Multifunctional Coatings I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Multifunctional Coatings II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Biomaterial Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269

Glass and Optical MaterialsGlass and Optical Materials I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49ACerS Alfred R. Cooper Session and Award: Performance Stability of Glass Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Glass and Optical Materials II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125

International Symposium on Innovative Processing and Synthesis of Ceramics, Glasses and CompositesFilms and Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49Mechanism/Kinetics of Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Microwave and Plasma Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Combustion Synthesis/Reaction Forming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156Rapid Prototyping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Polymeric and Chemical Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .222Composite and Powder Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254

NANOTECHNOLOGYControlled Processing of Nanoparticle Structures and Composites

Nanoparticle Sintering I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Nano-enabled Structure-Property Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Nanoparticle Sintering II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Suspension Control and Nanoparticle Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Nano-enabled Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Novel Nanoparticle Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Nano-enabled Devices I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255Nano-enabled Devices II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259

Nano-Materials for Electronic & Multifunctional ApplicationsNanoscale Synthesis and Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Nanotubes, Nanorods and Nanowires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194Nanoscale Films and Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195

Nanotechnology for Power GenerationNanotechnology for Power Generation I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224Nanotechnology for Power Generation II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256

Nanotube-Reinforced Metal Matrix CompositesProcessing Techniques for Nanotube-Reinforced MMCs I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Processing Techniques for Nanotube-Reinforced MMCs II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85Properties of Nanotube MMCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128

PROCESSING & PRODUCT MANUFACTURINGInternational Symposium on Ceramic Matrix Composites

Carbon Nanotube and Nanocomposites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Composite Processing and Characterization I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Ultra High Temperature Ceramics and Composites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .129Composite Processing and Characterization II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Ceramic Fiber Composites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195

www.matscitech.org vii

i-viii.MST_Abs.TOC.1st 9/3/08 3:03 PM Page vii

Joining of Advanced and Specialty Materials XFriction Stir and Solid-State Joining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Micro and Nano-Joining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Joining of Ceramics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196Welding Metallurgy and Welding in Nuclear Industry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .225Repair of Critical Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257

Micro-Manufacturing: Material Behavior, Deformation Mechanics, Process Control & ApplicationsMicro-Manufacturing I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Micro-Manufacturing II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87

Paradigm Shift in the Metals IndustryParadigm Shift in the Metals Industry I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52Paradigm Shift in the Metals Industry II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Paradigm Shift in the Metals Industry III . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132

Processing, Properties and Performance of Composite MaterialsModeling of Composite Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Metal Matrix Composites – Laminates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88Aluminum Matrix Composites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133Metal Matrix Composites – Nanocomposites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Properties of Composite Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Metal Matrix Composites – Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226Polymer Matrix Composites I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Polymer Matrix Composites II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .270

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvaniaviii

i-viii.MST_Abs.TOC.1st 9/3/08 3:03 PM Page viii

Su

nd

ay P

M

www.matscitech.org 1

Sunday, October 5, 2008

Keynote & Lectures

Frontiers of Science and Society: Rustum Roy LectureRoom: 304/305

5:00 PMSociety and M.S.T. Materials, Science and Technology: WhereGIGA outshines Nano (Invited)R. Roy*, Pennsylvania State University, USA

It is not by coincidence that it is our field of Materials Science/Tech-nology (MST) which stands at the junction of humanity’s enormoustechnological observation– plus–experimentation based achieve-ments. Materials embody the only proof of ideas, concepts, theories.“Scientia substania res”–to paraphrase Biblical wisdom. Few of ourown practitioners realize this central role of materials “science” in allof S/T. Philosophers and historians of S/T have long recognized this.Today’s S/T community including MST must fully grasp this, becausethe implications of this centrality of MST, are especially profound for:

• Science Education; K-12 to post Ph.D.• The disfunctionality of disciplinarity as the architectural

scheme of universities.• What MST curricula must include in the years ahead.• The obsolete-status of peer-review (of proposals and papers)

and simple, well-tested alternatives.• Re-designing public funding of research. The radical changes

needed in the current, failed, NSF and NIH systems incen-tivizing instead of punishing innovation. Return to timetested alternative.

• The negative consequences of “citation” data, and their misuse.• The corrupting role or “money” in all of science: from Nobel

prizes, to research funding of faculty.

It is time for MST to lead the so-called “science-community” awayfrom being “welfare queens in white coats” to responsible citizenswho as Einstein said should act…“in order that the creations of ourminds shall be a blessing and not a curse to humankind.”

Poster SessionRoom: Ballroom Foyer, 3rd Floor

6:00-8:00 PM

(ELEC-001) The Initial Oxidation Behavior of CuNi alloysobserved by in-situ UHV-TEMZ. Li*, J. C. Yang, L. Sun, University of Pittsburgh, USA

In order to extent the investigation of initial stage of oxidation from puremetal to alloys, we resume our study to the oxidation behavior of CuNialloys. Formation and evolution of oxide islands, oxide islands morphol-ogy, incubation time and the heteroepitaxial relationship between oxideislands and substrates will be investigated on the samples of Cu-2 at% Ni(001), Cu-8 at% Ni (001), Cu-15 at% Ni (001) and Cu-24 at % Ni (001)at P(O2)=5×10-4 torr and T=500 C~700 C . Preliminary study showedthat the initial oxidation behavior of Cu-24 at % Ni is similar to that ofCu (001) and CuAu (001) where oxide islands rapidly nucleate, grow andcoalesce; however there are some remarkable differences exist in two as-pects: 1) Secondary nucleation phenomenon of oxide islands, which isdifferent from the formation of stable saturation nuclei density of Cu andCu0.5Au0.5, is observed for the first time; 2) Polycrystalline Cu2O/NiOislands with some preferred orientations are observed surprisingly

(ELEC-002) Roles of Ba/Ti ratio on the Crystal Structure ofBarium Titanate PowdersC. Chang*, M. Tu, C. Su, C. Huang, National Cheng Kung University, Taiwan

The effect of Ba/Ti ratio on crystal structure and microstructure wasstudied using XRF, Raman spectra, XRD, SEM, and TEM. A series of

BaTiO3 powders were synthesized from high purity BaCO3 and TiO2powders with Ba/Ti ratio ranging from 0.98 to 1.02 at 1200oC calci-nation temperature for 4 h. The XRF results confirm the Ba/Ti ratioof these synthesized BaTiO3 powders is ranging from 0.98 to 1.02.The Raman spectra demonstrate that the BaTiO3 powders are tetrag-onal phase and without second phase. The XRD data show the a sig-nificant change in tetragonality (c/a ratio) with Ba/Ti ratio. The Ti ex-cess samples exhibit a higher tetragonality (c/a ratio = 1.0109) thanthat in Ba excess samples (c/a ratio = 1.0097). The SEMs show themorphology and the TEMs observe the domain structure of these Baexcess and Ti excess BaTiO3 powder samples.

(ELEC-003) Ferroelectric Properties of Ho-Doped BaTiO3CeramicsV. V. Mitic*, Faculty of Electronic Engineering, Serbia; V. Pavlovic, Faculty ofAgriculture, University of Belgrade, Serbia; V. Paunovic, M. Dragan, P.Petkovic, Z. Ljiljana, Faculty of Electronic Engineering, Serbia

Doped barium-titanate ceramic is attracting much interest for its ap-plication as resistors with a positive temperature coefficient of resis-tivity (PTCR), multilayer ceramic capacitors (MLCC), thermal sen-sors etc. In those article BaTiO3-ceramics doped with 0.01 up to 0.5wt. % of Ho2O3 were prepared by conventional solid state procedureand sintered up to 1350°C for four hours. The microstructure investi-gations were done with SEM-JEOL 5300 equipped with energy dis-persive spectrometer (EDS) system. It has been noticed that, with thehigher dopant concentration the abnormal grain growth is inhibitedand the grain size ranged from between 2-20 micrometers. In order tocorrelate the microstructure and dielectric properties of dopedBaTiO3-ceramics, the hysteresis loop and the capacitance and dielec-tric losses of the samples have been determined. Present results en-abled establishing parameters for the prognosis of ferroelectric prop-erties of BaTiO3-ceramics according to the triad synthesis(technology) - structure - property.

(ELEC-004) Predicting the morphotropic phase boundarycomposition in (Bi0.5Na0.5)TiO3-based lead-free piezoelectricceramicsW. Lee*, C. Huang, L. Tsao, National Cheng Kung University, Taiwan

A qualitative relationship between the morphotropic phase boundary(MPB) composition and the tolerance factor (t) in (Bi0.5Na0.5)TiO3-based piezoelectric ceramics was established. The t values of the MPBcompositions in BNT-based ceramics were at a nearly region, t ~ 0.991.To demonstrate it, two piezoelectric ceramic systems (1-x)(Bi0.5Na0.5)TiO3-x(Ba1-aSra)TiO3, a = 0.05 and 0.3 (abbreviated asBNBST5-x and BNBST30-x, x < 12%), were designed. The X-ray dif-fraction patterns and the lattice parameter calculations revealed thatthese two systems exhibited a single perovskite phase and a rhombohe-dral-tetragonal phase transformation. Besides, both the XRD analysisand property measurements confirmed that the MPB compositionswere BNBST5-06 and BNBST30-08, respectively. The results were agree-ing with the predictions and demonstrating that the MPB compositionshifts away from the BNT as the t of the non-BNT end member reduces.

(ELEC-005) Multiferroic Pb(Fe0.66W0.33)0.80Ti0.20O3 thinfilms: A room-temperature relaxor ferroelectric and weakferromagneticA. Kumar*, I. Rivera, R. Katiyar, UPR, USA

We report the synthesis of single phase Pb(Fe0.66W0.33) 0.80Ti0.20O3(PFWT20) thin films by chemical solution deposition techniques onPt/Ti/SiO2/Si(100) substrates. At room temperature it showed relaxorbehavior up to 50 kHz frequency and almost linear dielectric constantfor higher frequency. The dielectric diffusivity (γ=1.89) calculated frommodified Curie-Weiss laws and nonlinear Vogel-Fulcher fitting impliesrelaxor characteristics of the films. Capacitance variation as function ofapplied field showed perfect “butterfly loops” for frequency (>10 kHZ)at room temperature and for a full range of experimental frequenciesnear the freezing temperature (~ 240K). Magnetization vs. appliedmagnetic field displayed weak ferromagnetic properties.

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 1

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania2

(ELEC-006) Effect of SiO2 Interlayer to Plasma Resistance of Y2O3Coatings on the oxide substratesY. Oh, S. Lee, D. Kim, H. Kim*, KICET(Korea Institute of CeramicEngineering & Technology), South Korea; J. Lee, H. Kim, Inha University,South Korea

Plasma resistance of various oxide materials is important factors fordesigning the passive and active devices of the wafer processingequipment in the semiconductor industry. As the plasma conditionbecomes more severe, high erosion resistance materials such as Y2O3are widely adopted for that application. In this study, Y2O3 andoxynitride (Y-Si-Al-O-N) glass were investigated as main coating ma-terials and the amorphous SiO2-rich interlayer was used between thecoating and substrates. The SiO2 contents in the interlayer werechanged gradually or their thicknesses were controlled layer by layer.The plasma erosion resistances of the coated layers were measuredusing capacitor type etcher of dual frequency in the Si-etch condi-tion. Physical properties such as adhesion, hardness and elastic mod-ulus were checked using nano-indentation and microstructures wereinvestigated by SEM & EDS.

(ELEC-007) Crystal Habit Dependent Quantum ConfinedPhotoluminescence of Zinc Oxide NanostructuresI. J. Arellano*, R. V. Sarmago, L. M. Payawan, University of the Philippines,Philippines

Diverse zinc oxide crystal habits namely wires, rods, tubes, sheets,whiskers and tetrapods were synthesized via solution phase and car-bothermal reduction routes. The surface morphology of the nanos-tructures was analyzed via scanning electron microscopy (SEM). Themorphology and crystallinity of the as-synthesized nanostructure ar-chitectural motifs were related to their photoluminescence (PL). ThePL at 157 nm was taken using F2 excimer laser and a crystal habit de-pendent response was observed. Xray diffraction (XRD) analyseswere conducted to deduce the degree of crystallinity showing resultsconsistent with the excitonic emission at the band edge and visibleemission at the electron-hole recombination sites. PL emission spec-troscopy for the tetrapods exhibited an interesting PL reduction asso-ciated with high-energy deep traps in the nanostructures. Further-more, some intensity dependent characteristics were deducedindicating quantum confined properties of these nanostructures.

(ELEC-008) Fabrication and Properties of Ir/PZT/Ir Capacitors byLiquid Delivery MOCVDD. Xie, Y. Ruan, T. Ren, L. Liu, Tsinghua University, China; J. Cao*, Universityof Science and Technology Beijing, China

Pb(Zr,Ti)O3 (PZT) thin films were prepared on 8 inch and 4 inch Siand Ir-coated Si wafers by liquid delivery MOCVD using cocktailsources of Pb, Zr and Ti. It was found that the compositional unifor-mity depended on the wafer temperature uniformity greatly.Through optimizing the processing condition, such as depositiontemperature, deposition pressure, substrate rotation rate, gas flowand pressure etc, the best film growth conditions were obtained. Thethickness uniformity of PZT films on 8 inch substrate could be about±3.24%. The ferroelectric properties of Ir/PZT/Ir capacitors were ex-cellent with a remanent polarization of 22μC/cm2 and a coercivefield value of 40kV/cm. However, PZT films based on Pt substrateshowed poor ferroelectric properties. The reason may be due to thediffusion of Pb element, because it is found that the growth rate of Pbon Pt substrate was higher than that of Zr and Ti.

(ELEC-009) Epitaxial Growth of SnO2 Film on (001) TiO2Substrate by Excimer Laser-assisted Metal Organic Deposition atRoom TemperatureT. Tsuchiya*, National Institute of Advanced Industrial Science andTechnology, Japan; F. Kato, Chiba Institute and Technology, Japan; T.Nakajima, T. Kumagai, National Institute of Advanced Industrial Science andTechnology, Japan

In order to prepare the high performance device, the orientation con-trol of the film is effective. In this paper, we have successfully prepared

the epitaxial Sb-doped SnO2 film on the (001) TiO2 substrate usingELAMOD at a temperature range from 25 to 300°C. It was found thatthe crystallinity and conductivity of the film prepared at 25°C isgreater than that of the film prepared at 300°C. The resistivity of 2%Sb-doped SnO2 film was lowest when the Sb concentration ischanged from 1% to 10%. Based on the Hall measurements of thefilms prepared by ELAMOD and thermal MOD, the lowest resisitvityof the 2% Sb-doped SnO2 film was found to be caused by the highercarrier concentration in comparison with the film prepared by simplethermal process. Formation mechanism of the film is also character-ized by the TEM measurements, and the calculated film and substratetemperatures.

(ELEC-010) Measurement of non-180°° domain switching in PZTceramics under cyclic electric fieldsA. Pramanick*, J. Jones, University of Florida, USA

A novel time-resolved, laboratory X-ray diffraction technique usingCu Kα radiation has been developed. The technique is used to studythe change in non-180° domain fractions in La-doped, tetragonallead zirconate titanate (PZT) ceramics under sub-coercive cyclic elec-tric fields. This is achieved by synchronizing the applied electric fieldwith the collection of the diffraction patterns in time. The ratio of thevolume fractions of the non-180° domains in the material, repre-sented by η, is obtained from the ratio of the integrated intensities ofthe pseudocubic 002 diffraction peaks. During electrical cycling, thedifference in the values of η under high and low electric fields is re-lated to the change in the volume fractions of the non-180° domains.It is observed that the dynamic change in the volume fractions of thenon-180° domains is linearly dependent on the amplitude of the ap-plied electric field, which correlates with the Rayleigh law for con-verse piezoelectric effect.

(ELEC-011) Synthesis and Characterization of Lead Ferrite-Bismuth Ferrite Multiferroic CompositeA. Rossa*, Y. P. Cardona, R. Peréz, J. D. Jiménez, J. Silva, P. Vargas, O.Uwakweh, University of Puerto Rico, USA

The high energy ball milling process can create differences in thestructure therefore enhancing polarization and reducing grain sizes.Perovskite, 0.75Pb(Fe2/3W1/3)O3-0.25BiFeO3, was produced usingthe Spex Mixer 8000-D Mill. Perovskite was synthesized mixing PbO,Bi2O3, WO6 with (a) Fe2O3 or (b) Fe3O4. Samples were character-ized by X-ray diffraction (XRD), scanning electron microscopy(SEM). The aim of this investigation is realize both a spontaneous po-larization and magnetization at room temperature. This study tries tounderstand how ferroics properties in BiFeO3 ceramics can be en-hancement in a complex perovskite. An amorphous state was foundafter 5 hours ball milling with a reduction of particle size and disor-der effect. XRD results after heat treatment show an atomic reorgani-zation having the perovskite with Fe3O4 and an introduced of a newface in peroskite with Fe2O3. Characterization of Vibrating SampleMagnetometer (VSM) and Mössbauer Spectrometric Measurementsis in process.

(ELEC-012) Effect Of CoFe2O4 Coercivity By High Energy Ball MillJ. J. Silva*, Y. P. Cardona, R. Perez, A. Rossa, P. Vargas, O. N. Uwakweh,University of Puerto Rico in Mayaguez, USA

The effect of high energy ball milling on precast cobalt ferrite(CoFe2O4) leads to particle size and grain size reduction coupledwith both strain and coercitvity changes. Particle size reduction from70.46 nm to a minimum value of 10 nm was achieved for a minimumof 60 minutes ball milling. The strain induced on the milled materi-als reached a maximum of 0.006 after 3 hours of milling which re-mained unchanged with subsequent milling for up to 10 hours ofcontinuous milling. Maximum coercivity of 0.29 T corresponding to1 hour ball milling was observed, while continued ball milling led tocoercivity reduction to 0.097 T for a particle size of 9.46 nm corre-sponding to a strain of 0.0063. Totality of the results demonstrates

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 2

Su

nd

ay P

M

www.matscitech.org 3

that coercivity enhancement was not achieved with continuous parti-cle size reduction.

(ELEC-013) Hybrid Nanofractography of BaTiO3 ceramics by PFMand SNDMJ. Tatami*, S. Nakada, S. Tasaki, T. Wakihara, K. Komeya, T. Meguro,Yokohama National University, Japan

In this study, simultaneous evaluation of the crack and fracture sur-face profile and the electrical properties near the surface in BaTiO3ceramics was carried out using piezoresponse force microscope(PFM) and scanning nonlinear dielectric microscope (SNDM),which is named “Hybrid Nano-fractography”. The domain structuresin the grain were observed on the fracture surface, which were 0O /90O and 0O / 180O domains with straight and irregular domain walls,respectively. The domain structures observed by PFM and SNDMwere different depending on the detectable depth. Crack propagationbehavior on the polished surface was also observed. A crack inducedby Vickers indentation was slightly propagated by bending test. Do-main switching region extended during crack propagation in the oneside and the back of the crack tip, which was explained by the modelin consideration of local stress field at the crack tip.

(ELEC-014) Magnetic properties and microstructure of Soft andHard Ferrites MaterialsL. Rivas-Vázquez*, R. Suárez-Orduña, J. Hernandez-Torres, M. Valera-Zaragoza, Universidad del Papaloapan, Mexico; E. Rocha-Rangel, M. A.Romero-Romo, A. Altamirano-Torres, 2Universidad AutónomaMetropolitana, Azcapotzalco, Mexico

Soft and hard ferrites powders were prepared by the sol-gel methodand characterized by XRD, SEM and VSM techniques. The gel pre-cursor was characterized by the DTA analyses. The composition offerrites soft and hard prepared was Mn-Zn ferrite and Zn-Ti- substi-tuted barium ferrite powders, respectively. The magnetic properties atroom temperature were evaluated for different levels of dopant andheat-treatment temperatures. The magnetic properties of the hardferrites heat treated at 1000°C for 4 h were 60-65 emu/g and 5.4 kOefor the Magnetization of saturation and the coercitivity, respectively,with magnetoplumbite as a single phase. It was found that the varia-tion in the ratio Fe/Ba, Fe/Mn and Fe/Zn was effective in the controlof the magnetic properties, microstructure and composition ofphase. SEM micrographs showed that the crystallite average sizes forMn-Zn ferrites and Zn-Ti doped barium ferrite were below 100 nm,which decreased with the increase of the substitution level.

(ELEC-015) Structural, magnetic and dielectric properties ofmultiferroic CuFeO2P. P. Shojan, M. K. Singh*, G. L. Sharma, R. S. Katiyar, University of PuertoRico,, USA

Structural, magnetic and dielectric properties of a delafossite – typeoxide CuFeO2 has been studied. The thin films were grown on singlecrystalline sapphire substrates with c-axis orientation by rf sputteringmethod. The ceramic material of CuFeO2 was synthesize by sol gelprocess. The reitveld refinement analysis of X – ray diffraction dataindicates the formation of delafossite structure. Temperature depend-ent Raman spectra of CuFeO2 were measured from 80K to1273K andwe observed anomalous frequency and line width shifts with temper-ature, which were interpreted as an experimental evidence of com-bined effect of lattice expansion and anharmonic phonon – phononinteraction in CuFeO2. The magnetic susceptibility measurementshows the successive antiferromagnetic transition at 13 K (TN1) andat 9 K (TN2).

(ELEC-016) Pt/BiFeO3 /DyScO3 /Si MFIS structures for FeRAMapplicationsN. Murari*, R. Thomas, R. Katiyar, University of PuertoRico, USA

Fabrication of Metal- Ferroelectric- Insulator- Semiconductor(MFIS) structures is valuable in FeRAM applications as it preventsinter layer diffusion and reduces lattice mismatch between the ferro-

electric layer and the silicon substrate. But the generation of depolar-ization field and increase of the operation voltage is a concern andcan be overcome by introducing low ferroelectric and high bufferlayer. So we fabricated MFIS structure with 270nm of BiFeO3 and30nm of DyScO3 by chemical solution deposition method and Liq-uid Injection Metal Organic Chemical Vapor Deposition method, re-spectively. DyScO3 films on Si substrate were amorphous and smoothshowing negligible CV hysteresis. MFIS structures showed clock-wisehysteresis CV curves and a memory window ~ 0.7V. The operatingvoltage reduced with decreasing thickness of the ferroelectric filmand the buffer layer without sacrificing the memory window. ThusDyScO3 buffered BiFeO3 MFIS can be of interest in FeRAM devices.

(ELEC-017) Ferroelectric and magnetic properties of chemicalsolution deposited Bi(Fe0.9Ti0.05Co0.05)O3 thin filmsR. Malgerejo, N. Murari*, R. Thomas, R. Katiyar, University of PuertoRico, USA

The simultaneous occurrence of ferromagnetism and ferroelectricityat room temperature in BiFeO3 is promising for the realization ofnovel devices provided the high leakage current is reduced. Multifer-roic BiFe0.9Ti0.05Co0.05O3 films with Ti and Co double substitu-tion at the Fe site were prepared by chemical solution deposition.There was no shift in the 2q reflection positions ofBiFe0.9Ti0.05Co0.05O3 films compared to BiFeO3, showing per-ovskite structure with rhombohedral or pseudocubic symmetry.Temperature and frequency dependence of the dielectric constantand loss were studied. The leakage current reduced significantly andthe ferroelectric and the magnetic properties improved considerably.Hence the substitution of Ti and Co at the Fe-site improved the over-all properties of Multiferroic BiFeO3.

(ELEC-018) Effect of A-site Sr substitution on the orientation ofPb(Zr0.5,Ti0.5)O3 thin films on Pt(111)/TiOx/SiO2/Si substratesR. Thomas*, N. K. Karan, J. J. Saavedra-Arias, N. M. Murari, D. K. Pradhan,R. S. Katiyar, University of Puerto Rico, USA

Domain switch cycling degrades the polarization of ferroelectricPb(Zr0.5,Ti0.5)O3 and hence the realization of reliable integratedmemory devices is a concern. High stability associated with Sr-Obonding allows low density of oxygen vacancies and which in turn re-duce fatigue. The c-axis-oriented (Pb0.9Sr0.1)(Zr0.5,Ti0.5)O3 (PSZT)ferroelectric thin films were successfully prepared by the chemical so-lution deposition. From the X-ray diffraction studies, it was foundthat the orientation degree increases with the increase of annealingtemperature, and at the same time the grain morphology changes.The films were ferroelectric with the phase transition temperature(ferroelectric to paraelectric) at ~ 590K. The dielectric constant andthe loss tangent at room temperature were 530 and 0.06, respectivelyat 100 kHz. The remnant polarization and the coercive field were 11.4μC/cm2 and 68 kV/cm, respectively.

(ELEC-019) Structural and dielectric properties of strontiumdoped barium titanate stannate ferroelectric ceramics withdiffused phase transitionS. Yun*, D. Xu, School of Material Science and Engineering, Xi’an Universityof Architecture & Technology, Xi’an, 710055, China, China; X. Wang,Department of Materials Physics, School of Science, Xi’an JiaotongUniversity, Xi’ an, 710049, China, China

12 at.% strontium doped Ba1-xSrxTiO3 (BST, x=0.10, 0.20 and 0.30)ceramics prepared by the conventional mixed oxide method were in-vestigate. Sn doping significantly decreases the peak dielectric con-stant of BST ceramics and shifts the temperature of the peak dielec-tric constant to lower temperature for the different compositions.BST exhibits a normal-like ferroelectric behavior while a dielectric re-laxation behavior was observed in strontium doped BST, and the de-gree of the diffuseness and the relaxation of BST ceramics increasesafter introducing Sn. The results indicate that the selected system ex-hibits one broad dielectric peak in 12 at.% strontium doped BST ce-ramics with increasing x, i.e., the two phase transitions in BST ceram-ics are merged into one broad peak in 12 at.% strontium doped BST

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 3

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania4

ceramics. The abnormal dielectric behavior can be attributed to non-equivalence ions co-substitution to A- and B-site in ABO3 perovskitestructure.

(ELEC-020) Potential for textured bismuth titanate as a hightemperature piezoceramicT. Chavez*, C. DiAntonio, Sandia National Laboratories, USA

A quantum leap in the evolution of innovation can occur by develop-ment and re-design of components through novel materials, process-ing and fabrication techniques. This work moves away from ordinaryceramics with randomly oriented grains and isotropic properties tograin-oriented ceramics with anisotropy obtained by aligning thecrystal axis of each grain in a pre-determined direction. The preferredorientation provides a pathway to fabrication of ceramics with en-hanced piezoelectric and electromechanical properties. Molten saltsynthesis, coupled with shear induced orientation, has provided pref-erential crystallographic alignment to a highly textured bulk ceramic.The test vehicle to demonstrate this is the bismuth-layer structuredferroelectric compound bismuth titanate, Bi4Ti3O12. This materialand others in the bismuth layer-structured compounds family haveattracted considerable attention for their potential in high-tempera-ture piezoelectric devices and numerous other applications.

(ELEC-021) Features of Heterophase States in PMN–xPT SolidSolutions Near the Morphotropic Phase BoundaryV. Y. Topolov*, Southern Federal University, Russian Federation

The purpose of the study is to interpret examples of phase coexis-tence in the perovskite-type lead magnoniobate – lead titanate solidsolutions near the morphotropic phase boundary (0.30< x< 0.35). Inthis work two variants of experimental temperature dependence ofunit-cell parameters at x= 0.32 are used for a prediction of het-erophase states below Curie temperature. Domain state – interface di-agrams [1] are put forward to interpret heterophase states (e.g.tetragonal – monoclinic of the B type or tetragonal – monoclinic ofthe C type), the role of several domain types in forming a planar un-strained interface that separates the polydomain phases, and possiblescenarios of stress relief in wide temperature ranges. The studied het-erophase states and complete stress-relief possibilities are comparedwith those at x > 0.32 or x < 0.30, especially in the presence of the in-termediate monoclinic phases. [1] V. Yu. Topolov, H. Cao, and D.Viehland, J. Appl. Phys., v.102, 024103 (2007).

(ELEC-022) Comparative Analysis of ElectromechanicalProperties in Ferroelectric Perovskite-type CeramicsV. Y. Topolov*, Southern Federal University, Russian Federation

This work contains a review of electromechanical (i.e. elastic, piezo-electric and dielectric) properties in poled ferroelectric ceramicsbased on the perovskite-type oxides, such as barium titanate or leadzirconate-titanate. Over 30 complete sets of room-temperatureelectromechanical constants from experimental papers have beenanalysed to show important advantages and potential piezotechnicalapplications of these ceramic materials. An influence of electro-mechanical interactions in a ceramic medium on piezoelectric coeffi-cients, their anisotropy and electromechanical coupling factors of thestudied ceramics is discussed. An effect of domain structure and do-main-orientation processes in ceramic grains on the electromechani-cal properties has been considered using different model conceptsand published experimental data. Contributions from 90-degree do-main-wall displacements into electromechanical constants of thepoled ferroelectric ceramic of barium titanate have been analyzed.

(ELEC-023) Surface Analysis of Nano-structured Carbon NitrideFilms for MicrosensorsC. Chang*, J. Kim, Y. Jeong, Y. Seo, Kyungnam University, South Korea; S.Chowdhury, Intel Corporation, USA; S. Lee, Kyungnam University, South Korea

Carbon nitride films are deposited on silicon substrate by reactive RFmagnetron sputter with DC bias for microsensors. The surface analy-sis of deposited films is performed by AES, EDS, XPS, XRD and SEM.

The grain size of crystalline carbon nitride film, which has a gooduniformity, is about 30 nm and similar with a theoretical β-C3N4.When there is no pre-sputtering in the sample, the composition ratiodoes not change significantly according to the heat treatment condi-tions. However, when the sample is pre-sputtered before heat treat-ment, the carbon composition is increased and the nitrogen compo-sition is decreased on the subsurface, because the weak-bonednitrogen is removed during annealing. The EDS analysis shows thatthe chemical composition of the carbon nitride film is C2N. The im-pedance of CNx humidity sensor which had micro holes decreasesfrom 253kΩ to 4kΩ in the relative humidity range of 5 % to 95 %.

(ELEC-024) Impact of High Pressure Deuterium Annealing onElectrical Characteristics for 512Mb DRAMs with 80nm Design ruleH. Chang*, Korea Institute of Ceramic Engineering & Techology, SouthKorea; J. Suh, S. Hong, Hynix Semiconductor Co. Ltd, South Korea; M.Chang, H. Hwang, Gwang-ju Institute Science and Technology (GIST),South Korea; K. Choi, Korea Institute of Ceramic Engineering & Techology,South Korea

We investigated high pressure deuterium treatments and its impacton DRAM technology. High pressure deuterium annealing (HPDA)introduced during post metal anneal (PMA) improves not onlyDRAM performance but also reliability characteristics of MOSFET.In addition, it has been shown that data retention time through thedecrease of junction leakage currents using HPDA has been signifi-cantly improved.

(ELEC-025) Low-Temperature Polyol Synthesis of NanocrystallineCobalt and Cobalt-PlatinumJ. A. Pérez-Acosta*, university of Puerto Rico - Mayaguez, USA

The size-dependant magnetic properties of transition metal nanocrystalsfor magnetic storage is a key to new technology. High Ku (magnetocrys-talline anisotropy constant) nanostructures become very attractive for ul-trahigh density magnetic recording applications. Prominent candidatesare tetragonal intermetallic compounds (fct phases CoPt). The kinetics ofthe metal forming reaction strongly influences the stability conditions ofcobalt phases (we used a solution of Polyol-Co II). The hydroxyl ions, ac-celerated the formation of magnetic phases and their stability. Whenvarying the OH-/Co mole ratio and the type of cobalt salt used, differentphases were formed.Obtaining a metastable pseudo-cubic epsilon cobalt.The Pt ions cause a shortening of the time required for the magneticphase formation. This and a drastic quenching allowed the formation offace centered tetragonal CoPt nanoparticles. This is the first time that thedirect formation, with no need of annealing, of fct-CoPt is reported.

(ELEC-026) Understanding the Dielectric Behavior of(Sr0.8Pb0.2)TiO3-MgO Tunable Dielectric in Paraelectric PhaseJ. H. Wang*, H. Liu, Pennsylvania State University, USA; R. Guo, A. S. Bhalla,University of Texas at San Antonio, USA

The (Sr0.8Pb0.2)TiO3-MgO composite system has been studied bySomiya et. al. At room temperature, attractive relative permittivities(over 100) were obtained with an addition of MgO in (Sr0.8Pb0.2)TiO3.At the same time, low relative dielectric losses, tan(δ), in the range of 10-

4 to 10-3 were observed in the frequency range from kHz to 4GHz, re-spectively. In this study, finite element method with Monte Carlo simu-lation is conducted for the composition x (Sr0.8Pb0.2)TiO3: (1-x) MgOfrom x=0 to 1 in the paraelectric phase (from 220K to 450K), and the re-sults are computed and compared with the experimental data. The tem-perature dependence of the relative permittivity of composites was wellpredicted for materials in the paraelectric phase. The simulation resultsshow little discrepancy when compared with the experimental data.

(ELEC-027) Dielectric Behavior of (1-x) BaTiO3-x (Na1/4Bi3/4)(Mg1/4Ti3/4) O3L. Wu*, X. Wang, Xi’an Jiaotong University, China; R. Guo, A. S. Bhalla,University of Texas at San Antonio, USA

Solid solution compositions (1-x)BT-xNBMT (x 0.30) were synthe-sized. The XRD results show that when x<0.20, BT goes through a

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 4

Su

nd

ay P

M

www.matscitech.org 5

multiple phase transitions; at x 0.20 a single phase pseudocubic sym-metry was identified. From temperature dependent dielectric meas-urements, the three phase-transition temperatures corresponding toBT tend to merge with increasing NBMT content and finally the BT-NBMT exhibits a single diffuse phase transition at x 0.20. When x0.06, the permittivity, ε’, of the tetragonal-cubic transition peak isbroadened and transition remains frequency independent. Thestrong frequency dispersion of ε’ is observed below transition. In therange of 0.08 x 0.18, the saddle-back shaped ε’ versus T curve is ob-served, which disappears at x=0.20. When 0.06 x 0.18, the permittiv-ity does not strictly follow Curie-Weiss law for T>Tm, while forT>Ta(Tm-lower transition, Ta-upper transition), the calculated γ isclose to 1.

(ELEC-028) Novel Tunable Dielectric and Magneto-electricCompositesS. Agrawal*, J. Cheng, R. Guo, D. K. Agrawal, A. Bhalla, Pennsylvania StateUniversity, USA; S. Priya, University of Texas, USA

The composites of (Ba,Sr)TiO3:MgO and PMN-PT:NiMn0.1Fe1.9O4 were prepared to tailor the tunable dielectric properties andthe enhancement of magneto-electric coefficient properties. Thecomposites were synthesized with the combination of both micronand nano size particles to understand the effect of grain size and con-nectivity pattern on the resulted properties of the composites. Thetunable composites were processed in a multi-mode microwave ovenand the magneto-electric composites were processed in a single modemicrowave oven in pure electric or magnetic fields. The desired con-nectivity pattern of 0-3 was achieved in the composites with the useof micron/nano size particles and microwave processing. The maxi-mum tunability of 50% was achieved with the dielectric constantvalue of 100. In magneto-electric composites, the coefficient of 520mV/cm.Oe was observed for the composites sintered in a single modemicrowave oven.

(ELEC-029) Effects of BiScO3 addition on Dielectric Properties ofAcceptor-doped BaTiO3S. Jo*, SungKyunKwan University, South Korea; J. Hong, Samsung Electro-Mechanics, South Korea; Y. Han, SungKyunKwan University, South Korea

Effects of BiScO3 addition on the temperature stability of acceptor-doped BaTiO3 dielectrics were studied. Powders were prepared by aconventional ceramic processing technique. Formation of the per-ovskite structure was confirmed by X-ray diffraction analysis and nosecond phase was detected. As the BiScO3 content was increased, theCurie temperature (Tc) slightly moved to higher temperatures. Thesample doped with 2 mol% BiScO3 exhibited the highest dielectricconstant at room-temperature (~2400). The addition of Ho2O3-MgO-MnO-BiScO3 yielded fine grains and relatively higher dielec-tric constants at room temperature, compared with that of the sam-ple singly-doped with BiScO3. The addition of BiScO3 improved thetemperature stability of dielectric properties of acceptor-dopedBaTiO3 over the entire temperature range studied (-55~150°C).

(ELEC-031) Effects of non-stoichiometry on dielectric andpiezoelectric properties of Pb-free Bi based ferroelectric titanateceramicsY. Sung*, H. Lee, H. Yeo, T. Song, M. Kim, Changwon National University,South Korea

In developing Pb-free Bi based ferroelectric titanate ceramics includ-ing (Bi0.5Na0.5)TiO3 (BNT) and (Bi0.5K0.5)TiO3 (BKT), depolar-ization temperature (Td) and piezoelectric constant (d33) are twokey properties for practical applications. These dielectric and piezo-electric properties are very much dependent upon not only the com-positional variables of each system itself such as non-stoichiometry,doping, etc. but also the compositions between them such as mor-photropic phase boundary (MPB). Those properties so far reportedare rather inconsistent and furthermore none of those matches withproperties of Pb(Zr,Ti)O3 (PZT) based ceramics. In order to improvethose properties in a reproducible manner with better understand-

ing, in this study, effects of non-stoichiometry on the dielectric andpiezoelectric properties of Bi-based ferroelectric titanate ceramicswere investigated.

(ELEC-032) Standardization of bending impact test of lead freesolder paste jointJ. Park*, RIST, South Korea

Concern to lead free solder increase such environment regulation asRoHS. As use of lead free solder increase, intermetallic compoundformed at interface between solder and pad is main issue because ofweakness on drop impact. To simulate drop situation, drop impacttest methods is conducted, however, which is time consuming and ex-pensive. As a indirect evaluation method of drop impact for lead freesolder joint, we standardized bending impact test methods by cyclicbending fatigue machine. To obtain optimum test condition, bendingamplitude, frequency, and number of specimen were studied. Suit-able bending amplitude and frequency were 5-10mm range and 2.5-10Hz range respectively. Optimum test numbers were obtained bystatistical methods and 5 times.

(ELEC-033) Dissolution Kinetics and Diffusion of Cobalt in Pb-free Sn-Bi-In-Zn-Sb Soldering AlloysK. Barmak*, D. C. Berry, Carnegie Mellon University, USA; V. G. Khoruzha, V.R. Sidorko, K. A. Meleshevich, A. V. Samelyuk, V. I. Dybkov, Institute forProblems of Materials Science, Ukraine

To avoid the excessive loss of solid metals in contact with liquid sol-ders, data on metal dissolution rates in solder melts are needed. Inthis work, the dissolution kinetics of cobalt in Pb-free 87.5%Sn-7.5%Bi-3%In-1%Zn-1%Sb and 80%Sn-15%Bi-3%In-1%Zn-1%Sbsolders have been studied at 250-450°C. The dissolution process isdescribed by the Nernst-Shchukarev equation and can be character-ized by two quantities, namely, the solubility or saturation concentra-tion and the dissolution-rate constant. Their experimental values,and also diffusion coefficients of cobalt in liquid solders calculatedfrom the Levich and Kassner equations, are presented. Although thesolubilities of cobalt in the solders at a given temperature differ con-siderably, the dissolution rate constants are very close and vary in therange (1-9) × 10–5 m s–1 at disc rotational speeds of 6.45 to 82.4 rads–1. The same applies to the diffusion coefficients of cobalt, which fallin the range (0.16-2.02) × 10–9 m2 s–1.

(ELEC-034) Chemical Solution Deposited Ba[(Ni1⁄ 2,W1⁄ 2)0.1Ti0.9]O3 Thin Films for High Energy Density CapacitorsApplicationsD. K. Pradhan*, N. K. Karan, J. J. Saavedra-Arias, R. Thomas, R. S. Katiyar,University of Puerto Rico, USA

Pulsed power in mobile systems requires high-k dielectrics as highenergy density capacitors for energy storage and power compressiondevices. Ba[(Ni1⁄2,W1⁄2)0.1Ti 0.9]O3 thin films were fabricated by chem-ical solution deposition technique and the films were crystallized inthe perovskite phase at temperature ≥ 700°C. The dielectric constantand the loss tangent values at 100 kHz were 85 and 0.007 at 300 K.The temperature and frequency dependence of the dielectric constantand the loss tangent were small close to room temperature(300±25K). At low temperatures (≤300K), the breakdown field wasalmost temperature independent with a value of ~3.0 MV/cm [signif-icantly higher compared to BaTiO3 (0.45MV/cm)]. High capacitancedensity (3.1 fF/μm2) along with high energy density (34 J/cm3) andlow leakage current at room temperature signify high potential forthis material in integrated circuits and power electronic applications.

(ELEC-035) The Effect of Type of Glass on the MechanicalProperty of BaTiO3 Ceramics for MLCC ApplicationS. Ryu, H. Kim*, H. Kim, Korea Institute of Ceramic Engineering andTechonology, South Korea

As the need for multilayer ceramic capacitor(MLCC) of high capaci-tance with small size increases, the number of dielectric ceramic lay-ers increases and the thickness of the ceramic layers decrease, which

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 5

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania6

can cause mechanical failure due to the density difference betweeninner laye with electrode and margin layer. Therefore, the improve-ment of the strength of the sintered ceramic body has become an im-portant for producing MLCC chip with no structural defect. In thisstudy, the influence of type of sintering aid on mechanical property ofBaTiO3 ceramics was investigated. Two different glasses of BaO-CaO-SiO2 and BaO-ZrO2-SiO2 were used as sintering aid for the densifi-cation of BaTiO3. Mechanical properties of sintered BaTiO3 ceramicswere analyzed by measurements of bending strength and surfacehardness by nanoindentation.

(ELEC-036) Building nanostructured cathode-electrolyteinterfaces for high efficiency thin film SOFCJ. Yoon*, R. Araujo, Texas A&M University, USA; A. Serquis, InstitutoBalseiro-Centro Atomico Bariloche, Argentina; H. Wang, Texas A&MUniversity, USA

In order to increase the effective area of triple phase boundaries(TPB), thus improving kinetic performance, we built a verticallyaligned nanocomposite (VAN) layer in between the cathode and theelectrolyte, which is composed of both cathode and electrolyte mate-rials, in our case La0.5Sr0.5CoO3 (LSCO) and Ce0.9Gd0.1O1.95(CGO). This layer effectively increases the cathode-electrolyte inter-face area, and thus improves the interface gas diffusion efficiencywhich leads to the overall improved thin film SOFC performance.The VAN interlayer was deposited on various substrates (SrTiO3,YSZ, and pressed CGO disks) using pulsed laser deposition technique(PLD). Microstructures and electrochemical properties of the cath-ode/VAN interlayer/electrolyte stacks were characterized by cross-section TEM, and SEM, and the electrochemical measurements, re-spectively. In addition, the binary VAN interlayer could act as atransition layer and improve the adhesion between the cathode andthe electrolyte.

(ELEC-037) Electronic structure and electronic transportproperties of BaPrO3 doped with YbT. Higuchi*, Tokyo University of Science, Japan; S. Mimuro, S. Miyoshi,University of Tokyo, Japan; K. Kobayashi, NIMS, Japan; P. Glans, Y. Liu, P.Yao, J. Guo, Lawrence Berkeley National Laboratory, USA; Y. Oyama, S.Yamaguchi, University of Tokyo, Japan

The electronic structure of BaPr1-xYbxO3-delta has been examinedusing both advanced soft X-ray Emission and Absorption Spec-troscopy, and the discussion on the relation between electronic bandstructure and its peculiar conductivity behaviors is presented. A softX-ray Absorption Spectroscopy, Resonant Inelastic Soft X-ray Scat-tering, and Soft X-ray Emission Spectroscopy have been used for theobservation of unoccupied sate and occupied state. The results showpeculiar band structure with a pair of occupied and unoccupied stateof Pr4f orbital’s, suggesting the strong correlation between <Pr3++L-1> and <Pr4+>. Both Pr levels are reduced by the introduction ofYb3+ ions possibly due to the instability of <Pr3+>.

(ENVIRO-001) Characterization of Vitrified Savannah River SiteSB4 Waste Surrogate Produced in Cold CrucibleS. Stefanovsky*, SIA Radon, Russian Federation; J. C. Marra, SRNL, USA; A.Akatov, Institute of Technology, Russian Federation; O. Stefanovsky, SIARadon, Russian Federation

Savannah River Site SB4 waste surrogate with high aluminum andiron content was vitrified with Frit 503-R4 (8 wt.% Li2O, 16 wt.%B2O3, 76 wt.% SiO2) using lab- (56 mm inner diameter), bench-(236 mm) and large-scale (418 mm) cold crucible induction melters(CCIM). The waste loading ranged between 40 and 60 wt.%. The vit-rified products obtained in the lab-scale CCIM were nearly amor-phous with traces of unreacted quartz at 40 wt.% waste loading andtraces of spinel phase at 50 wt.% waste loading. The bench-scaleCCIM glass was composed of major vitreous and minor iron-richspinel phase whose content at ~60 wt.% waste loading was ~10vol.%. The glass produced in the large-scale CCIM was composed ofmajor vitreous and minor spinel phases with ~12 vol.% crystallinity.

The anionic motif of the glass network is built from rather shortmetasilicate chains and boron-oxygen constituent based on boron-oxygen triangular units.

(ENVIRO-002) Capacitance of ZnO Under UV LightC. Su, C. Huang, C. Tsai*, C. Chang, National Taipei University ofTechnology, Taiwan

The capacitance of zinc oxides (ZnO) under ultraviolet (UV) light isstudied. ZnO discs were heated at temperatures ranged from 500 to1300 degrees centigrade. Field emission scanning electron mi-croscopy (FESEM)is used to confirm abruptly-increased graingrowth and density for ZnO heated at temperatures higher than 1100degrees centigrade.The relative density reaches 95.87% and the hard-ness become 1.703 GP for ZnO heated 1300 degrees centigrade. Re-sults of Raman spectrum analysis show that less oxide defects exist inZnO heated at higher temperatures. It is found that the capacitance ismeasured as 18 nF for ZnO sintered at 1300 degrees centigrade and israised to 24 nF under UV light illuminating for 30 min.The influenceof heating temperature on microstructure and performance of ZnOdiscs is also discussed.

(ENVIRO-003) Vitrification of Radioactive Hospital WasteIncineration AshP. Stoch*, Institute of Atomic Energy, Poland; M. Ciecinska, AGH - Universityof Science and Technology, Poland; A. Stoch, Institute of Electron TechnologyKrakow Division, Poland

Vitrification of a hospital 137Cs contaminated waste incineration ashby comelting with Na-borosilicate glass was studied. Mechanism ofthe ash dissolution in a host glass, during heat treatment of ash andglass mixture and accompanying recrystallization processes werestudied, using XRD, FTIR, DTA, DSC, SEM and EDS methods. Influ-ence of Cs incorporation on the change of structure of glass and itsproperties were subject of the investigations. Increase of glass trans-formation temperature Tg and change of the specific heat capacityvalue accompanying the transformation are one of the visible effectsof the structural changes. CaO as the main component of ash in-creases the tendency of glass for crystallization. Cs is incorporatedinto the structure of newly forming crystal phases which are chemi-cally resistant alumino-siliactes : nepheline and pollucyte. Experi-mental results were compared with MDM simulation data.

(ENVIRO-004) Nanowell-like Growth of AgInSe2 Films for SolarCell ApplicationsD. Pathak*, R. Bedi, D. Kaur, GNDU-Physics, India

AgInSe2 (AIS) films were grown on glass substrate kept at 473K bythermal evaporation technique. The starting material were stoichio-metrically mixed Ag, In and selenium powders. The film thicknesswas controlled during deposition by means of quartz crystal monitorand was kept near 1.5 μm. X ray diffraction pattern indicate that thefilm and as prepared powder of AgInSe2 have preferential texture in(112) direction .The prepared AgInSe2 films have single phase withpredominant (112) orientation. Crystallite size has been calculatedfrom FWHM value of the (112) peak by using Scherrer’s equationand is observerd 11 nm for the films prepared at 473 K. The surfacemorphology of the films studied from AFM. It depicts nano well typestructures with depth of 250 nm. The variation of absorption coeffi-cient (α) as a function of wavelength λ (nm) has been studied fromoptical absorption data.

(ENVIRO-005) Plutonium Usage and Management in PWRA. E. Mohamed*, ims, Egypt

Main limitations due to the enhancement of the plutonium contentare related to the coolant void effect as the spectrum becomes faster,the neutron flux in the thermal region tends towards zero and is con-centrated in the region from 10 Ke to 1 MeV. Thus, all the capturesby Pu240 and Pu242 in the thermal and epithermal resonance disap-pear and the Pu240and Pu242 contributions to the void effect be-came positive. The higher the Pu content and the poorer the Pu

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 6

Su

nd

ay P

M

www.matscitech.org 7

quality, the larger the void effect. This paper discusses the differentsolutions to be used to overcome the difficulties that effect, on safetyparameters and on reactor performance, and analyses the conse-quences of plutonium management on the whole fuel cycle like (rawmaterials savings, fraction of nuclear electric power involved in thePu management. All through two types of scenario, one involving alow fraction of the nuclear park dedicated to plutonium manage-ment, the other involving a dilution of the plutonium in all the nu-clear park.

(ENVIRO-006) Sintering Behaviour of (La, Ca, Sr)1-xMnxO3 as anActive Magnetic Material for Magnetic Refrigeration at RoomTemperatureI. Biering*, M. Menon, N. Pryds, Risø National Laboratory for SustainableEnergy, Technical University of Denmark, Denmark

Magnetic refrigeration is a promising new technology for energy effi-cient and environmentally friendly cooling. When a magnetic mate-rial is subjected to an alternating external magnetic field it createstemperature changes which can be utilized in a heat pump cycle. Per-ovskite manganites are potential materials for practical applicatione.g. in the form of plates. The overall goal of the present study is to es-tablish the connections between functionality of these materials, andthe processing parameters used in their synthesis and shaping. Pow-ders of (La, Ca, Sr)1-xMnxO3 were synthesized and consolidated bypressing and sintering. The structure, morphology, sintering abilityand magnetocaloric properties of these bulk samples were examinedas a function of composition using VSM, DSC, SEM and XRD. Fi-nally, processing sintering path is suggested to offer a rapid and cost-effective route for the production of component plates.

(ENVIRO-007) Serpentinite Materials from Slovakia Inertized byMicrowave TreatmentsC. Leonelli*, D. N. Boccacccini, P. Veronesi, University of Modena and ReggioEmilia, Italy; M. Kovacova, S. Cuvanova, S. Jakabsky, Slovak Academy ofSciences, Slovakia

The asbestos was widely used mainly in building industry in the lastcentury. The main source of asbestos in Slovakia was mine in Dob-sina, where after closing the mining activity in 1998 stayed at the heaparound 1.3 milion tons of serpentinite, which belongs to the group ofasbestos`s minerals. The main components of serpentinite are SiO2and MgO that should be applied as refractory material after destroy-ing the fibre structure. This investigation was focused on the mi-crowave inertisation of serpentinite waste. Microwave energy is easilyabsorbed by the OH-containing serpentine structure, hence the insu-lating property of the material is bypassed. Serpentine samples washeated in microwave furnace (single and multimode) at frequency2.45 GHz and absorbed energy in material was measured. Accordingto ESEM measurements, the fibre structure resist up to 1000°C.

(ENVIRO-008) Processing Fly Ash from Coal Burning PowerStation in a Variable Radiofrequency FieldI. Lancellotti, L. Barbieri, F. Andreola, C. Leonelli*, University of Modena andReggio Emilia, Italy; M. La Robina, Institute of Materials Engineering,Australian Nuclear Science and Technology Organisation, Australia

The purpose of this experiment was to verify if induction heatingcould melt fly ash from a coal-burning power station in a more rapidmanner than conventional heating. Experiments were conducted inthe cold crucible facility at ANSTO using a new 30kW variable fre-quency generator configured as a standard Hartley oscillator with thetank capacitor able to vary from 110 pF to 4100 pF giving a frequencyspan of 5MHz to 18MHz. The applicator consisted of a coil with awater cooled base and top plate that formed an LC resonant cavity,which coupled to the RF generator by a single turn coil. A dark glasswas formed by applying a high frequency electromagnetic field be-tween two copper plates through a sample of fly ash. The tempera-tures reached were in excess of 1000°C causing the powder to fuseinto glass in a brief time of few minutes.

(ENVIRO-009) Structural and Electrochemical Properties ofLiMn0.5Ni0.5-xCoxO2 (X=0.2-0.3): A Cathode Material forSecondary Lithium-ion BatteriesJ. J. Saavedra-Arias*, N. K. Karan, A. Kumar, D. K. Pradhan, R. Thomas, R. S.Katiyar, University of Puerto Rico, USA

New generation cathode materials with lower costs and toxicities, andhigh discharge capacities to replace LiCoO2 are of great importancein Li-ion rechargeable batteries. However, the alternate layered mate-rials, like, LiNiO2 and LiMnO2 are not having the structural stabilityunder repeated electrochemical cycling. We therefore selected a com-bination of Ni, Co and Mn layered cathode materials in order to im-prove the stability. One such material, namely LiMn0.5Ni0.5-xCoxO2cathode material was synthesized by conventional ceramic route andannealing conditions were optimized for the single-phase formationof the layered structure. The structural properties were investigatedusing X-ray diffraction, and Raman Spectroscopy and showed or-thorhombic structure with R-3m symmetry. Cyclic Voltametry andthe galvanostatic charge-discharge showed promising results andhence addition of Co in Li(Mn,Ni)O2 is a promising way to improvethe stability.

(ENVIRO-010) Adsorption of Cadmium Ions Using Low-costMaterialsM. R. Chaves*, P. M. Büchler, São Paulo State University, Brazil; E. R. Dockal,São Carlos Federal University, Brazil; R. R. Souza, Amazonas FederalUniversity, Brazil

The Permeable Reactive Barriers and Zone of Reaction are technolo-gies used in the remediation of soil and contaminated groundwater.The adsorption is the processes physical-chemical that can be estab-lished in these barriers. However, the use of expensive adsorbentssuch as activated coal can raise the cost of these technologies. In thisway, the development of research on the toxic heavy metal removalwith materials of low cost is of great utility and importance. The silicaproduced by rice hulls ash had been evaluated as adsorbent of lowcost, with potential to be used in reactive barriers. This work presentsthe adsorption capacity of Cd2+ in aqueous medium through batchmethod, presented for the silica xerogel obtained from rice hulls ashin comparison the different low cost adsorbent materials. The resultsdemonstrated that the prepared silica presented superior adsorptioncapacity in relation to the studied adsorbents.

(ENVIRO-011) Corrosion of Materials in Molten SaltsK. Sridharan*, L. C. Olson, J. W. Ambrosek, D. C. Ludwig, Y. Chen, M. H.Anderson, L. Tan, T. R. Allen, University of Wisconsin, USA

Molten salts have many desirable thermo-physical properties such ashigh thermal conductivity and specific heat, low melting point andhigh boiling point, and low viscosity that make them attractive candi-date media for heat transfer and storage applications. Molten saltshave been used for thermal energy storage in solar energy applica-tions and are presently being considered as media for transfer ofprocess heat from high temperature nuclear reactor for the produc-tion of hydrogen. However, materials corrosion is a significant issuein molten salts, particularly in the fluoride and chloride salts that arebeing considered for nuclear reactor based hydrogen production. Ex-perimental challenges associated with corrosion testing and corro-sion performance of a number of high temperature alloys including,Incoloy 800H, Haynes 230, Hastelloy, as well as silicon carbide inmolten fluoride salt, FLiNaK (LiF-NaF-KF: 46.5-11.5-42 mol %), willbe presented.

(ENVIRO-012) Processing and dielectric properties ofNanostructured TiO2 film made by tape casting methodS. Chao*, V. Petrovsky, F. Dogan, Missouri University of Science andTechnology, USA

Nanosized TiO2 powder with a specific surface area about 40m2/g was successfully adapted for tape casting technique. The in-fluence of different solvent systems, type of dispersants and

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 7

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania8

amount of dispersants on the rheological behavior of the slurrywas studied so as to find out the optimum slip composition. It wasfound that the sinterability of the tape was greatly affected by theaddition of phosphate ester as dispersant. Electric and dielectricproperties of the tapes such as conductivity, current-voltage char-acteristics dielectric constant, dielectric loss and polarization-electric filed relations were measured and related to microstruc-tural features. The influence of residual phosphorus left byphosphate ester on the dielectric properties of the tape was alsodiscussed.

(ENVIRO-013) EBSP study of hydride precipitation behavior inZr-Nb alloysS. Nishioka*, M. Ito, H. Muta, M. Uno, S. Yamanaka, Graduate School ofEngineering, Osaka University, Japan

Zr–Nb alloys have a uniform distribution of β-phase particles. In thisstudy, Effects of β-phase on hydride precipitation behavior were in-vestigated. The preparation processes of Zr-1.0 wt%Nb and Zr-2.5wt%Nb were the same as that for the commercially supplied recrys-tallized Zircaloy-2. The specimens were hydrided by a modified Siev-erts’ UHV apparatus at different temperatures. Hydride precipitationbehavior and microscopic texture of these specimens have been ex-amined by electron backscattering diffraction patterns (EBSP) meas-urement. The formation of β and δ-hydride phase in the specimenshas been studied with their morphology, habit plane and orientationrelationship with the α matrix. The habit planes of hydride phasehave been determined and compared with those observed in otherstudies. The microscopic texture and hydride precipitation behaviorobtained by EBSP were consistent with the results obtained by XRDand TEM studies.

(ENVIRO-014) Preparation of CuInS2 Films by Electrodeposition:Effect of Metal Element Addition to Electrolyte BathT. Honjo*, M. Uno, S. Yamanaka, Osaka University, Japan

The ternary semiconductor CuInS2 is suitable for use in solar cells.The compound has direct bandgap energy of 1.5 eV and high lightabsorption coefficient. We succeeded in making CuInS2 thin film byelectrodeposition technique. In this study, we fabricated Ga incorpo-ration in CuInS2 films in order to control the bandgap energy byadding Ga3+ ion into the solution. The electrodeposition was carriedout in a three-electrode system, using SUS304 plate as a working elec-trode. The solution for deposition contained desirable concentrationsof Cu2+, In3+, Ga3+, S2O3

2- and LiCl, and the pH value was adjustedwith a buffer solution of pH=3. Deposition was performed potentio-statically. After the electrodeposition, the films were annealed in avacuum. The deposited film made in the solution with Cu2+:Ga3+

=2:1 contained about 4 at.% Ga. The film had p-type conductivityand its bandgap value was 1.6 eV.

(ENVIRO-015) Variable Charge Molecular Dynamics Simulationof Intergranular Films in SiC CeramicsY. Ma*, Xiangtan University, China; S. H. Garofalini, Rutgers, the StateUniversity of New Jersey, USA

The presence of amorphous films at grain boundaries in ceramics is ageneral feature of the liquid phase sintered covalent materials and anumber of macroscopic properties of those materials, such asstrength, toughness, creep behavior, are affected by the intergranularfilms (IGF). Molecular dynamics (MD) simulations are often used toinvestigate the structure and chemistry of the IGFs at atomistic level.In this work, MD simulations are used to study the IGFs in SiC ce-ramics. To account for the partial ionicity in SiC and its IGFs, electro-static interactions are included. Furthermore, to allow for a more re-alistic description of the disordered structure in IGFs, charges oneach atom are allowed to change during the course of the simulationbased on the electronegativity equalization principle. Charge transferbetween the IGFs and their neighboring crystals are observed and theequilibrium film thickness is found to be dependent on the chargetransfer.

(ENVIRO-016) Characterization of Composite Nitride PelletPrepared by SPS TechniqueH. Muta*, K. Kurosaki, M. Uno, S. Yamanaka, Osaka University, Japan

The nitrides is a good candidate as nuclear fuel of FBR and ADS dueto the wide solubility between (U,Pu)N and MAN(MA:minor ac-tinide). Conventionally, long milling process and high sintering tem-perature were necessary for fabrication of the high density pellets. Inthis study, TiN, ZrN, DyN, UN and their composites were preparedby carbothermic method and palletized by Spark Plasma Sintering(SPS) technique. SPS is a pressure-assisted sintering that utilizes anelectric current. The concentrated electric current activates a surfaceof the sample particles in the process and drastically decreases thesintering temperature and time. Pellets with 90 % of theoretical den-sity were obtained with low sintering temperature within 30 minuteswithout any milling process. The result indicates that application ofthe SPS technique can restrain an evaporation of minor actinide inthe sintering process.

(ENVIRO-017) Thermal expansion and elastic moduli ofYt0.08ZrO2, Sc0.1Ce0.01ZrO2, Sc0.11Ce0.002ZrO2 andGd0.2Ce0.8O2 electrolyte materials for Solid Oxide Fuel Cells as afunction of temperatureT. Manisha*, M. Radovic, Texas A &M University, USA; N. Orlovskaya,University of Central Florida, USA; B. Armstrong, Oak Ridge NationalLaboratory, USA

In an attempt to determine thermal stresses, thermo-mechanicalcharacterization of various electrolyte materials for solid oxide fuelcells (SOFCs) has been performed in temperature range 25-900C inair. Electrolyte materials studied in present work include Yt0.08ZrO2,Sc0.1Ce0.01ZrO2, Sc0.11Ce0.002ZrO2 and Gd0.2Ce0.8O2. Coeffi-cient of thermal expansion (CTE) and elastic properties namelyYoung’s (E), shear (G) moduli have been determined as a function oftemperature using Thermo-mechanical Analyzer (TMA) and Reso-nant Ultrasound Spectroscope (RUS) respectively. These thermo-me-chanical properties have been found to be a strong function of tem-perature, composition and residual porosity. In the case of scandiaand ceria doped zirconia, a decrease in elastic moduli has been ob-served with increasing concentration of dopants.

(ENVIRO-018) Chromium incorporation into SOFC cathodematerials and effects on electrical propertiesB. Jiang*, S. Chao, J. Jung, D. D. Edwards, S. T. Misture, Alfred University, USA

Incorporation of Cr3+ into SOFC cathode materials along with elec-trical behavior were studied to develop a basic understanding ofchromium poisoning from metallic interconnects. The reactivitystudies were performed over a range of oxygen partial pressures andunder hydrogen for LSC, LSCF and BSCF using Cr2O3, Crofer 22 andE-brite as Cr sources. Diffusion couples and bulk mixed powdersdemonstrate that BSCF is least reactive, with Cr penetrating only~100 microns after 7 days at 850°C. In contrast, LSC and LSCF reactto completion at temperatures as low as 600°C. The diffusion profilesfor Cr into the cathode is quantified using electron microprobeanalysis. The effects of the foreign ion on the electrical behavior wasalso determined using ac impedance measurements to 1000°C in air.

(ENVIRO-019) Increased Thermal Stability of Infiltrated NickelAnode Catalysts on YSZ Scaffolds by Chemical AnchoringTechniquesC. Law*, S. Sofie, Montana State University, USA

The addition of chemical anchors into YSZ electrode scaffolds havebeen investigated as a means to limit degradation of nickel infiltratedSOFC anodes. Utilizing carbon and graphite thermal fugitives,porous YSZ substrates were prepared for infiltration studies as a base-line testing medium. Aluminum titanium oxide and nickel oxide, inlow concentrations of 5-10%, were separately introduced into theporous YSZ anode scaffolds prior to the sintering process. The nickelcatalyst was infiltrated by means of a fully saturated nickel nitrate so-

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 8

Su

nd

ay P

M

www.matscitech.org 9

lution containing a pine oil based surfactant for pore penetration.Concentration of nickel in addition to catalyst stability testing bySEM and conductivity testing will be reported.

(ENVIRO-020) The effect of Al2O3 addition on the sinteringbehavior of 10% Y2O3 - 10% ZrO2 - CeO2 (mol %)G. S. Godoi*, D. P. Souza, Federal University of São Carlos, Brazil

The effect of 0.5 %mol of Al2O3 on the sintering behavior of 10%ZrO2 -10% Y2O3 - CeO2 (mol %) (CZY) were investigated by con-stant heating rate dilatometry (CHRD) and scanning electron mi-croscopy (SEM). The additive enhanced the sinterability of the pow-der compacts. However, low densities were obtained for samplessintered at lower heating rate even on the additive presence. Mi-crostructure analysis by SEM confirmed that the sintering occursthrough liquid phase mechanism. The heating rate has strong effecton the amount and distribution of the liquid phase produced duringsintering which determines the densification degree attained.The ac-tivation energies at the initial stage of sintering were also evaluated byanalyzing the densification curves.

(ENVIRO-021) Novel Single-chamber Solid Oxide Fuel CellDeveloped with E-beam/Photo Lithography TechnologiesZ. Xu, North Carolina A&T State University, USA; M. Yang*, S. Desai, NorthCarolina A&T State University, USA; D. Kumar, J. Sankar, North CarolinaA&T State University, USA

Nano scale thin film electrolyte enhanced the electrical conductivitysignificantly. Single-chamber(S-C) SOFCs shows excellent simplifyand reliability. To take advantages of the outstanding in-plane con-ductivity of thin film electrolyte and reliability of S-C SOFC, the au-thors have developed a novel S-C SOFC by lithography and vapordepositions. In this study, nanostructured thin film electrolytes ofsingle layer and multilayered Ce-SSZ : Al2O3 were prepared withpulsed laser deposition (PLD) in the patterns created with lithogra-phy methods. The electrodes were produced either by vapor deposi-tions or by soft-lithography. The effects of the layer thickness of theelectrolytes as well as the distance between of the electrodes on theconductivity were studied with ac impedance. Fuel cells with inter-digitized structure of electrolyte and electrodes have been developedand tested. The study showed a great potential of this novel type offuel cell in the future application

(ENVIRO-022) Gd-doped ceria (GDC)/Y-doped zirconia (YSZ)bilayer electrolytesT. Dias*, D. P. Ferreira de Souza, UFSCar, Brazil

GDC electrolytes have been considered the best option for substituteYSZ electrolytes on SOFC technologies. However, the reductive at-mosphere on the anode side induces electronic conduction on GDCdecreasing the cell performance. This problem may be solved apply-ing fine layer of YSZ on anode side GDC electrolyte surface. In thiswork GDC/YSZ bilayer samples were prepared by pressing layers to-gether obtained by tape casting. GDC powder (Ce0.8Gd0.2O2-δ) wasprepared by oxides mixture and YSZ was from Tosoh. Appropriateamount of organics addictives were used for prepare the slurries.Tape thickness was controlled through the slurry viscosity, doctorblade height and speed of carrier movement. Monolayers thickness ofGDC and YSZ stayed between 700-100 and 150-15 micrometers, re-spectively. Bilayer samples were sintered at 1600°C for 1h following aspecific program. Mono and bilayer samples were characterized byimpedance spectroscopy and scanning electron microscopy.

(ENVIRO-023) Zinc Oxide Microstructural Architecture showingEfficient Photocatalytic Activity towards the Degradation ofMethylene Blue and Rhodamine BI. J. Arellano*, R. V. Sarmago, L. M. Payawan, University of the Philippines,Philippines

Immobilized zinc oxide microstructural architecture was synthesizedvia carbothermal reduction in an oxidative muffle furnace. These di-verse ZnO crystal habits were characterized using field emission scan-

ning electron microscope (FESEM), Xray diffraction (XRD) and pho-toluminescence (PL). The synthesized architecture was used as pho-tocatalyst in the degradation of methylene blue (MB) and rhodamineB (RB). The photocatalytic degradation rate constants for methyleneblue are 0.0406, 0.0156 and 0.0138 min-1 for 10 ppm, 25 ppm and 50ppm, respectively. The rate constants for rhodamine B are 0.0132,0.0242 and 0.0192 min-1, for 5 ppm, 10 ppm and 25 ppm, respec-tively. For uncatalyzed reaction, a rate constant of 0.0010 and 0.0009min-1 for MB and RB were calculated, respectively. The efficiency ofthe degradation is dependent on the initial pH of the solution and anoptimal activity was observed at pH 7.

(ENVIRO-024) Novel Ceramics Fabrication for Reducing ProcessSteps and Energy Consumption -Development of CompactProcessing TechnologyK. Watari*, T. Shirai, M. Yasuoka, Y. Hotta, AIST, Japan

Conventionally the manufacturing of ceramic parts consists of vari-ous processes such as pulverization of raw materials, dispersion, mix-ing, drying, shape forming, removal of organic binder, sintering andmachining. We proposed novel manufacturing processes using mi-crowave technique, a technique named “compact process”, for the sig-nificant enhancement of manufacturing speed and ultimate improve-ment of productivity of ceramics fabrication, in which thecomplicated operations are reduced to simplified processes. In thisreport, the effects on the characteristics of sintered body and decreas-ing of energy consumption by compact process will be discussed.

(ENVIRO-025) Mechanical properties of PET- Portland CementCompositeL. Rivas-Vázquez*, R. Suárez-Orduña, M. Valera-Zaragoza, E. Ramírez-Vargas, Universidad del Papaloapan, Mexico; E. Rocha-Rangel, M. A.Romero-Romo, A. Altamirano-Torres, Universidad AutónomaMetropolitana, Azcapotzalco, Mexico

The effects of waste polyethylene terephthalate (PET) bottles light-weight aggregate (WPLA) as admixture agent in Portland cement atdifferent addition ratios from 1% to 12 %, were investigated. The re-inforced samples were prepared according to the ASTM C 150 Stan-dard (samples of 5 x 5 x 5 cm). The reinforcing fibers were millingwith two different sizes, i.e., 5/16 and 1/8 in diameter, from wastepolyethylene terephthalate (PET) bottles and used them to evaluatethe effects in mechanical properties in cement-based composites. Theevaluation of PET as additive was based on result of density and com-pression tests. The 28-day compressive strength of cement reforcedwith WPLA at a replacement ratio of 12 % was 10 MPa compared tothe control concrete (7.5 MPa). The density of cement replaced withWPLA varies from 2114.7 kg/m3 (0 % WPLA) to 1991.04 kg/m3 (12% WPLA) by the influence of WPLA.

(ENVIRO-026) Structural Evolution and Mechanical Properties ofClays Sintered with Additions of CaF2 NanoparticlesO. Dominguez*, M. Lomeli, Instituto de Metalurgia, Mexico; H. Valle, R.Torres, Mexichem Fluor, Mexico; J. Cruz, Instituto de Metalurgia, Mexico

Global warming is now a powerful driving forces to induce industrialchanges. Concerning traditional ceramics, reduction of the sinteringtemperature can lead to important reduction of CO2 emissions. Dif-ferent additives like Na2CO3 and CaCO3 have been used but themain disadvantage is that during decomposition they release moreCO2. In the present work, different amounts of nanometric CaF2(from 0.625 to 5.0 wt%) were mixed with two materials, purifiedkaolinite and a conventional ball clay. CaF2 nanoparticles were ob-tained using aqueous solutions of CaCl2 dissolved with a dispersantand aqueous solutions of HF. In this case, the nanometric powdershad a mean particles size of 30 nm. The thermal evolution of the syn-thesized nanocomposites were characterized using XRD, DTA/TGA,IR, SEM and TEM. Results indicated that the sintering process can beshifted by almost 100°C and emissions of fluoride compoundsavoided.

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 9

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania10

(ENVIRO-027) Deterioration of Waterproofing Sheets in BuildingSubstructureV. Husakova*, CTU in Prague, Czech Republic

In everyday life we have to face deterioration of various kinds of ma-terials. It is clear that all kind of materials change their properties intime. In this article we will focused on degradation of materials whichare used in building construction. In this article, there will be ana-lyzed influences which may bring about physical and chemical degra-dation of bitumens and plastics waterproofing membranes in foun-dations. The problem of deterioration waterproofing membranes isimportant because the aim of this membranes is to prevent the pene-tration of subsurface water and radon into structures as well as theinterior of underground parts of buildings.

(ENVIRO-028) Preparation of Metal Oxide Photocatalyst by SoftSolution Process Using Anion Exchange ResinY. Kamo*, M. Uno, S. Yamanaka, Osaka University, Japan

Photocatalysts are expected for removing an environmental pollutantonly with solar energy. Generally, the photocatalic powders are syn-thesized with high energy process such as the solid-phase synthesisand gas-phase process now. On the other hand, there is a concept formaking high performance material directly from solution, in soft andenvironmental friendly condition, which is called soft solutionprocess. In this study, we successfully prepared nano-particles ofmetal oxides using the ion exchange reaction. We focused on thefunction of anion exchange resin as the removal materials of anion,which affects the equilibrium reaction and promotes precipitation ofmetal hydroxide or oxide. In the case of ZnO, the average particle di-ameter was 9 nm at minimum. The sample calcined at 573 K showedthe highest photoactivity under irradiating UV light. Afterwards, thebasic physical properties of the as-prepared photocatalyst were char-acterized by TG-DTA, XRD, FE-SEM, BET, and UV-Vis.

(ENVIRO-029) Arsenic Removal from Ground Water Using NovelNanomaterialsV. RaviRaj*, B. Mandal, VIT University, India

Groundwater remediation by nanoparticles has received tremendousinterest in recent years. The objective of the present study is to syn-thesize and characterize the starch stabilized zerovalent iron nanopar-ticles and perform the batch scale studies for the removal of arsenic.The starch stabilized nanoparticles displayed much less agglomera-tion than those prepared without a stabilizer. The absorption spectraof the solution before and after reduction were compared. Before re-duction there was a peak at 302 nm. After reduction the spectrumdisplayed a monotonic dispersion as the wavelength increased. Thesuspension was also taken for characterization studies using TEM.The dimensions and the morphology of the particles with and with-out starch are compared. Some trials studies were also performed tocheck the removal of arsenic concentrations using FI-HG-AAS.Ap-preciable results were observed with the trial studies and then pro-ceeded to evaluate the size-removal relationship.

(ENVIRO-030) Calculation of distribution on depth of structuresof the introduced ions In and As in SiA. Togambayeva*, Al-Farabi Kazakh National University, Kazakhstan; F.Komarov, Belarus State University, Belarus

The spatial distributions of the introduced ions and radiating defectsat irradiation of Si by ions of As and In are described. The structuresof distribution of ions In, As on depth are calculated. The calculationof distribution of impurity on depth was carried out by way of mod-eling spectra until the complete agreement with the experimentallymeasured structures. The form of structure of the implanted atomsand radiating damages with the growth of energy of ions becomesmore and more asymmetric with the clear expressed peak of concen-tration on depth of a target. The maximal concentration In is regis-tered on depth 50 nm. On spectra of Rutherford’s opposite dispersionthe distribution of impurity of As and In on the depth is received. It is

shown, that the “hot” conditions of the implanted impurity result tothe “blur” of structures In and As and lessening of the maximal con-centration of the implanted impurity in comparison with the data ofmodeling with use of the program SRIM’2006.

(FUND-001) Upper Bounds for Coarsening: TemperatureDependenceA. Novick-Cohen*, Technion, Israel; A. Shishkov, Institute of Applied Mathand Mechanics, Ukraine

Coarsening is considered in the context of the Cahn-Hilliard equa-tion with a concentration dependent mobility and with a tempera-ture dependent free energy. Upper bounds on coarsening are ob-tained for arbitrary mean concentrations and for all temperaturesbetween 0 and the critical temperature. We demonstrate that transi-tions may take place in the nature of the coarsening bounds as coars-ening progresses.

(FUND-002) Deformation Microstructures of Mg Alloys Inducedby Sliding Contact at Elevated TemperaturesS. Das*, University of Windsor , Canada; A. T. Morales, General Motors R&DCenter, USA; A. T. Alpas, University of Windsor , Canada

Laboratory scale tribological tests were performed in order to under-stand the microstructural changes induced on sheet Mg alloys duringhigh temperature sliding. Two different Mg alloys (AZ31 and AZ91)were studied at temperatures ranging from room to 673K. Duringsliding of Mg alloys at elevated temperatures, material transfer andadhesion are caused by plastic deformation. The plastic deformationhas been correlated to the grain boundary sliding mechanism at thattemperature. Electron back scattered diffraction techniques are beingused to study the orientation changes in the grains of transferredmaterial as well as the subsurface of worn samples along the slidingdirection.

(FUND-003) Atomistic Study of Structure and Failure of fcc/bccHeterophase BoundariesA. Hashibon*, University of Karlsruhe, Germany; C. Elsaesser, Fraunhofer-Institut fuer Werkstoffmechanik (IWM), Germany; Y. Mishin, George MasonUniversity, USA; P. Gumbsch, Fraunhofer-Institut fuer Werkstoffmechanik(IWM), Germany

The structure and mechanical properties of the technologically im-portant Cu-Ta interface system are investigated by atomistic molecu-lar dynamics and static energy minimization methods, employing anew angle dependent interatomic potential. Initial models with wellknown low energy orientation relationships for fcc/bcc interfaces areconsidered. The optimal interface structure is found by a combina-tion of vacancy formation energy profile calculations and thermalannealing. It is found that for the equilibrium interface structure, thefirst layer of Cu has a distinct structure from the rest of the fcc Cu lat-tice. This layer facilitates the transition from the bcc to the fcc crystalstructures across the interface. Mechanical failure under tensile stressis found to occur above the first Cu interface layer. The properties ofthis specific layer, its role in interface adhesion, and dislocations at theinterface will be presented.

(FUND-004) Phase field modeling of island formation in thinfilms under the influence of stress centersA. Boyne*, M. D. Rauscher, S. A. Akbar, S. A. Dregia, Y. Wang, The Ohio StateUniversity, USA

In previous work, we have shown that gadolinium doped ceria thinfilms deposited on yttria-stabilized zirconia substrates can developperiodic arrays of single crystal islands upon subsequent de-lamina-tion and heat treatment. It has been observed that these features tendto form near centers of surface stress. In the present work we describeefforts to further quantify this relationship. We have analyzed the ini-tiation of the islands within the framework of the Asaro-Tiller-Grin-feld instability, which describes the tendency of a stressed surface toroughen. Using a phase field model that is able to describe consis-tently both the stress state and the morphological evolution of a

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 10

Su

nd

ay P

M

www.matscitech.org 11

stressed surface, surface roughening and island formation are exam-ined as a function of the source of surface stress. Experimentally ob-served surface structures that may serve as the centers of surface stressare used in the simulations. The simulation results are compared withexperimental observations.

(FUND-005) Reception of Ceramic Aluminum Silicate CastablesIntended for Aluminium Electrolytic TankB. Sereda*, S. Sheyko, I. Krugljak, V. Sharapova, ZSEA, Ukraine

In this work the properties, characteristics and phase structure ofdense chamotte products received with use of the additive mullitecorundum chamotte (C-45) is resulted. The lead comparative analy-sis of products C-43 and C-45 has shown, that in products C-45 theinterstice share in diameter of 1-4 mm is about 67 % and in productsC-43 is about 51,5 %. The open porosity has made about 8%(C-45)and 12% (C-43). The average apparent density of C-45 – 2,43 gramper sm3, C-43 is 2,29 gram per sm3. The glass phase in products hasthe following optical properties Ng=1,477-1,498 and Np=1,546-1,606. The mass fraction of chemical elements in mullite is following:Al 38,8 %, Si 11,2 %, Ti 1,1 %, Fe 0,24 %. Element structure of glass isfollowing: Al 7,6 %, Si 30,5 %, Ti 1,7 %, Fe 3,8 %, Ca 4,5 %, Mg 2,8 %,K 0,6 %. Microhardness of mullite joints, cemented by glass layers, inproducts C-45 makes 1234 HV.

(FUND-006) A Study Of Oxide Defects On Surface Of ZnO FilmsC. Su, C. Huang*, C. Chang, C. Tsai, National Taipei University ofTechnology, Taiwan

The study aims at oxide defects in the ZnO films prepared at varioustemperatures. ZnO powders of average size of 255 nm were mixed withalcohol and then were spread on (100) silicon (Si) substrates by spin-coating. ZnO films were heated at temperatures ranged form 300 de-grees Celsius to 1300 degrees Celsius by a programmable furnace. Thesizes of preferably-oriented grains were determined using FWHManalysis based upon XRD measurement. The relative intensities ofcharacteristic (101)-peak are higher for ZnO films heated at highertemperatures. FESEM is used to examine surface morphology of as-ob-tained ZnO films. The electrical resistances were found to be decreasedfor those ZnO films heated at higher temperatures using both fourpoint probe measurement and LCR-meter. Raman spectroscopy analy-sis shows the relative intensity of E1 (415 cm-1) peak is higher for filmsprepared at higher temperature. The characteristic of the wurzite struc-ture is more accentuated in those films heated at higher temperatures.

(FUND-007) Relative Grain Boundary Sliding in a Three PhaseSuperplastic Alumina – Zirconia – Mullite CompositeC. Hoo*, L. Taherabadi, D. Men, Q. Ying, M. Mecartney, University ofCalifornia, Irvine, USA

Relative grain boundary sliding in a three-phase superplastic ceramicafter compressive deformation was measured using atomic force mi-croscopy (AFM) to investigate the contribution of sliding between dif-ferent grain boundaries to the total deformation of the composite. Thealumina (40 vol%), zirconia (30 vol%) and mullite (30 vol%) composite(AZ30M30) had an average grain size of 0.3 μm and was deformed incompression under constant stress conditions at 1400°C up to 20%strain. Of the six different types of grain boundaries (alumina/alumina,zirconia/zirconia, mullite/mullite, alumina/zirconia, alumina/mulliteand zirconia/mullite) it was found that the average grain boundary slid-ing displacement of each of the six types of boundaries yielded similaraverage displacement values suggesting that cooperative grain boundarysliding occurs in AZ30M30. Additional results from x-y displacementsmeasured in the scanning electron microscope will also be discussed.

(FUND-008) Overview of Recent Results in Simulation ofDislocation NucleationM. A. Tschopp, Universal Technology Corporation, USA; G. Tucker, D. L.McDowell*, Georgia Tech, USA

Results of recent atomistic simulations of dislocation nucleation infcc Cu and Al are summarized, including: (i) applicability of the

structural unit model for energy of general high angle boundaries,(ii) non-Schmid character of nucleation of partial dislocations fromthe interface due to tensile stress applied normal to the boundary(NPT ensemble), as well as homogeneous nucleation, (iii) lack of in-crease of tensile strength associated with CSL structures, (iv) strongtension-compression asymmetry of nucleation, (v) strong effects ofboundary inclination on faceting and nucleation, and (vi) effects offree volume arrangement and density. Some implications for finitetemperature kinetics are discussed.

(FUND-009) Enhanced Conversion of Polycrystalline Ceramics toSingle Crystals Using Selected DopantsG. C. Wei*, A. M. Scotch, Osram Sylvania, USA

Conversion of polycrystalline ceramic to single crystal was first re-ported in BaTiO3 and MnZn ferrites, and then in piezoelectric PZN-PT and PMN-PT.Translucent MgO-doped polycrystalline alumina(PCA) was converted to sapphire tubes. Co-dopants of MgO plusY2O3, or plus Y2O3 and ZrO2 retarded the conversion. Ga2O3dopant reportedly enhanced the conversion rate; it was attributed toaccelerated diffusion of Mg along boundaries. Mo dopant was alsofound to enhance conversion.The conversion of PCA to sapphire bylocally addition with SiO2 to trigger abnormal grain growth wasdemonstrated.More recently, boron dopant has been explored tospeed up the conversion of PCA. While a better understanding is re-quired for the structure of boundaries, and the mechanisms of inter-face transport involved, the experiments showed a significant en-hancing effect on conversion due to the boron-based dopant. Theresults will be disclosed, and compared with other reports of the ef-fects of dopants on conversion.

(FUND-010) Effects of Particle Shape on Measured Particle SizeG. Thiele*, M. Poston, L. Dudu, T. Thornton, P. Bouza, MicromeriticsAnalytical Services, USA; R. Brown, MVA Scientific Consultants, USA

Particle size analysis is a commonly performed test with a broadrange of applications encompassing virtually all industries. Numer-ous techniques exist for measuring particle size distribution, most ofwhich express the results in terms of equivalent spherical diameter.However, when the particles are not spherical, different measurementtechniques produce different particle size distributions for a givensample. Understanding what the particle size technique actuallymeasures, how it performs the measurement, and the key assump-tions around which the technique is based are crucial when selectinga particle size technique for your sample or application. Samples ofglass beads, garnet, and wollastonite were selected for their shape fea-tures; spherical, cubic, and rod-shaped particles respectively. The par-ticle size distribution of each material was analyzed using laser lightscattering, x-ray sedimentation, electrical sensing zone, dynamicimage analysis, and scanning electron microscopy. The results clearlydemonstrate the effect particle shape can have on the reported parti-cle size. Each technique showed good repeatability using the samesample with the same technique. However, it is important to under-stand that different techniques will produce potentially dramaticallydifferent particle size results and that the different in the results are tobe expected.

(FUND-011) Preparation and characterization of silica nanorodsG. Zhu*, Beijing Information Technology Institute, China

A simple method is presented for the preparation of silica nanorodswith a diameter of about 400nm with smooth surface. The silicananorods were synthesized by chysical vapor deposition method. Thesynthesized samples were characterized by means of scanning elec-tron microscopy, transmission electron microscopy and Raman spec-troscopy. The results show that synthesized silica nanorods have auniform size, well-defined shape, and smooth surface, and the mor-phology and microstructure of silica nanorods are affected by synthe-sis conditions, such as synthesis temperature, synthesis time, and pro-tection of gas flow rate etc.. The possible the growth mechanism of

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 11

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania12

silica rods in this process is proposed, and a possible multiple-reac-tion model was proposed to explain the formation of silica nanorods.The present method has some advantages such as simple experimentset-up, flexible synthesis conditions, and large area synthesis of silicananorods.

(FUND-012) Oxygen Transport and Growth Kinetics of OxideFeatures at the Aluminum-Sapphire InterfaceS. Dutta, H. M. Chan*, R. P. Vinci, Lehigh University, USA

A study of solid state oxidation at the aluminum-sapphire interfaceprovides insights into the metal-ceramic interaction and low temper-ature inward oxygen diffusion behavior. Annealing of Al thin films onc-plane sapphire substrates leads to the formation of sub-surfaceoxide features at the interface. Removal of the remnant metallic Al re-vealed hollow, truncated pyramidal structures surrounded by lowridge-like α-alumina walls. The coated substrates were subjected toisochronal heat treatments and the number density of the interfacialfeatures were calculated as a function of time. Use of different anneal-ing environment showed the effect of presence of oxygen on the den-sity of the interfacial features and their morphology. Our findingshelped us to understand the kinetics of low temperature oxygen dif-fusion for which limited data is available.

(FUND-013) Study on Analyzing the Fabrication Process of MetalMatrix CompositesI. Ss, K. Shankar*, S. Krishnan, Anna University, India

Metal matrix composites refer to a family of metal -based materialsreinforced with fibre, whisker or particulate, which can produce con-siderable alteration in the physical and mechanical properties of basemetal. In this paper a detailed study is made on the analysing the fab-rication process of Metal Matrix Composites (Al-Al203, AlSiC) andtheir applications. One of the fabrication process, squeeze castingprocess is explained in detail. The machining and finishing operationof MMC is also discussed.

(FUND-014) Twinning of TiO2 Precipitates in Sapphire MatrixJ. He*, GE Consumer & Industrial Lighting, USA; P. Lagerlof, A. Heuer, CaseWestern Reserve University, USA

Ti-doped sapphire single crystal was annealed at 1200c. TiO2 non-twinned precipitate of alpha-PbO2 structure was first formed. As itgrows, it formed twinned precipitate and further transformed itscrystal structure into rutile structure as a mechanism to minimizestrain energy. Kachaturyan’s method was used to calculate the strainenergy of twinned and non-twinned TiO2 precipitate, twinning inter-face energy of alpha-TiO2 and rutile precipitate was estimated basedon the observed critical twinning precipitate size. High ResolutionTransmission Electron Microscopy (HRTEM) was used to character-ize the twinning interface. The twinning was concluded to be growthtwinning rather than mechanical twinning.

(FUND-015) Alumina Dissolution Rate into Glasses that MimicGrain Boundary ChemistryK. J. DeCarlo*, T. F. Lam, B. Ponack, K. Strong, W. Carty, Alfred University, USA

Many ceramics are sintered via the liquid-phase because it allows forlower sintering temperatures to be used. During liquid-phase sinter-ing some of the grain material will dissolve into the grain boundary.Since liquid-phase sintered ceramics do not have the same grain sizeit is important to understand the effect that grain size has on the dis-solution process. Samples were prepared using alumina grains dis-persed in a glassy matrix, used to mimic a typical grain boundary,which was then heat treated and then air quenched. The grain sizesused, holding temperature, and holding time were all varied. Thestudy demonstrated that grain size does not affect dissolution rate.This indicates that diffusion, rather than dissolution is the rate limit-ing step of the process and that the grain, regardless of its size, willdissolve at the same rate consistent with other studies addressing, forexample, mullite.

(FUND-016) Origins of Grain Boundary Resistance for Oxide IonConduction in Ziconia by Molecular DynamicsM. Yoshiya*, Y. Yoshizawa, K. Shimizu, H. Yasuda, Osaka University, Japan; T.Oyama, Murata Manufacturing Co. Ltd., Japan

Lattice discontinuity at grain boundaries brings about grain bound-ary (GB) segregation, enrichment of foreign atoms or defect species.This significantly modifies characteristics of GB for transport phe-nomena, including ionic conduction. The modification at the GB isinevitable in poly-crystals and is referred to as “GB resistance” since itoften results in the decrease in ionic conduction across GB. In orderto obtain physical insight of structure-chemistry-property relation-ship at GB molecular dynamics simulation has been carried out to in-vestigate local ionic conductivity at symmetric tilt GBs with sponta-neous segregation in zirconia. It is found that local ionic conductivityacross GBs dropped from that in grain interior, resulting in the GBresistance. Further analysis revealed that the resistance is correlatednot only with lattice discontinuity at GB but also with local chemistrymodified upon segregation.

(FUND-017) Influence of the Silica Nanoparticles on theCrystallization Behavior of the Cesium Hydrogen SulfateM. Kislitsyn*, California Institute of Technology, USA

Cesium hydrogen sulfate (CsHSO4) can crystallize in one of twomonoclinic forms at room temperature, with phase III being the sta-ble phase and phase II metastable. Under ambient conditions, phaseIII preferentially crystallizes from aqueous solutions. Here the influ-ence of 10 nm SiO2 on the phase behavior of CsHSO4 is explored.Addition of collodial silica to aqueous solution precursors ofCsHSO4 was found to lead to preferential crystallization of phase II.The volume fractions of phase II, phase III, and amorphous materialfor composition spanning from entirely CsHSO4 to entirely SiO2were quantified using X-ray powder diffraction and solid state NMRmethods, with results of the two techniques showing good correspon-dence. Knowledge of the phase behavior in the presence of silica is animportant first step towards assessing the role of SiO2 on the protontransport properties of CsHSO4.

(FUND-018) Cross-interface Diffusion in Fiber DrawingNanomanufacturingM. Su*, Z. Ma, Y. Hong, University of Central Florida, USA

The cross-interface diffusion at high temperature is an omni-pre-sented phenomenon. Due to the small feature sizes, such diffusion innanostructured materials would have a profound effect on propertiesof materials. We have used fiber drawing nanomanufacturing tomake long nanowire arrays. In this method, a glass tube is filled withpower or rod of an appropriate material, and drawn into long fibersat high temperature. The long fibers are cut to short and even length,and stacked together for the next drawing. By repeating the simpledraw-cut-stack process, both the diameter and the spacing betweenfilling materials will decrease. The method has been used to makemicro/nanowires of metal, semiconductor, and inorganic materialswith minimal diameters between 200 to 700 nm. The cross-interfacediffusion is believed to have a predominant role in determining thediameter, structure, and quality of the wires. We will discuss the effectof materials and drawing conditions on the cross-interface diffusion.

(FUND-019) Cohesive Strength of Metal/Ceramic InterfacesFe/M[C,N] and the Role of Misfit Dislocations and SurfaceRoughnessO. Y. Kontsevoi*, A. J. Freeman, G. B. Olson, Northwestern University, USA

The dispersed inclusions of carbides and nitrides were shown toprovide superior fracture toughness for steels. We investigated thetheoretical cohesive strength of Fe/M[C,N] (M=Ti,V,Nb,Mo) in-terfaces using the ab initio FLAPW calculations. For the coherentinterfaces, the theoretical strength of 3.89 J/m2 was obtained forthe Fe/TiC interface, and it decreases from Ti-V-Nb-Mo. Thestrength of nitride interfaces is lower than for carbides. Within the

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 12

Su

nd

ay P

M

www.matscitech.org 13

Peierls-Nabarro model with generalized stacking fault energetics,we estimated that the misfit dislocations decrease the interfacestrength by 20%. The strength of semicoherent interfaces thatcontain primary misfit dislocations was found to be 30% lower.The effect of interface steps and roughness on strength is also in-vestigated. We identify the origins of strong interfacial bondingbased on electronic structure and charge densities analyzes. Sup-ported by the ONR through Dynamic Microstructure DesignConsortium.

(FUND-020) Effect of Impurities on Grain Boundary Strength inChromiumO. Y. Kontsevoi*, A. J. Freeman, Northwestern University, USA

Chromium shows great promise as a high-temperature structuralmaterial due to the combination of high melting point, good oxida-tion resistance, low density and high thermal conductivity. Unfortu-nately, it lacks ductility at low temperatures connected with light el-ement impurities; however, the exact mechanism of theirdetrimental effect is not clear. We determined the effect of segregatedC, N, O impurities on the cohesive properties of a Cr Σ3[110](111)grain boundary by means of first-principles FLAPW calculations ofthe decohesion process. The ideal tensile strength of the grainboundary increases in the presence of C and N impurities and de-creases with O additions. Coincidently, the work of separation is in-creased by C and decreased by N and O segregation. Thus carbonacts as grain boundary cohesion enhancer, oxygen as an embrittler,while segregated nitrogen weakens the grain boundary but increasesits resistance to crack nucleation. Supported by the AFOSR (grantNo. FA9550-07-1-0174).

(FUND-021) Effect of Impurity Segregation on Grain BoundaryCohesion of AlS. Zhang*, O. Kontsevoi, A. Freeman, G. B. Olson, NorthwesternUniversity, USA

The embrittling and cohesion-enhancing effects of H, B, Na, Mg, Cuand Zn on a Σ5(012)[100] aluminum grain boundary are investi-gated by means of the full-potential linearized augmented plane-wave (FLAPW) method with the generalized-gradient approxima-tion (GGA) formula within the framework of the Rice-Wangthermodynamic model. Analysis of the atomic and electronic struc-tures identifies the roles of atomic size and the bonding behavior ofthe impurity with the surrounding Al atoms. The results show thatH, Na, Mg and Zn are embrittlers, that B acts as a cohesion enhancerand that Cu has a mild effect on grain boundary cohesion. Thiswork provides a fundamental electronic level understanding ofstress corrosion cracking in Al alloys and aids in the design of highstrength Al alloys. Work supported by the AFOSR (grant No. FA9550-07-1-0174) and the Ford-Boeing Nanotechnology Alliance atNorthwestern.

(FUND-022) Role of Grain Boundary Complexions in theSintering of Undoped and SiO2-doped Y2O3S. Ma*, C. Kiely, M. Harmer, H. Caram, Lehigh University, USA

A new concept of interface complexion has been proposed. It recog-nizes grain boundaries as distinct “phases”, which have complex andimportant three-dimensional structure at the atomic level. In thepresent research program, we have performed a fundamental graingrowth kinetic study of the sintering of yttrium oxide nanoparticleswith the aim of understanding the factors that favor the formation ofa dense, nanograined, optically transparent ceramic material. Over anarrow temperature range an abrupt increase in grain growth rateand a significant discontinuity in grain boundary mobility have beenidentified. Chemical analysis and preliminary transmission electronmicroscopy indicates that such a grain growth transition is correlatedwith a grain boundary structural (complexion) transition which isassociated with silica impurities segregated to the grain boundary.The effect of a deliberate silica doping was also investigated.

(FUND-023) Wetting of Liquid Metals on Multiphase CeramicsW. Jackson*, University of Pittsburgh, USA; C. Eckert, Apogee Technology,Inc. , USA; F. S. Pettit, G. H. Meier, University of Pittsburgh, USA

The interfacial properties of ceramics and liquid metals are impor-tant in many industries, notably, in the creation of ceramic-metal ma-trix composites, and in the processing of metals. This study looks at amodel system, Cu, NiO-YSZ to study the interfacial phenomena be-tween liquid metals and multiphase ceramics which have differentwetting properties. Emphasis will be placed on the effect that the ce-ramic microstructure has on the properties of the system. Theseproperties were investigated using the sessile drop technique, and mi-crostructural characterization was performed using optical and scan-ning electron microscopy.

(FUND-024) Segregation and Disordering at Tungsten GrainBoundaries in Well-Quenched SpecimensX. Shi*, J. Luo, Clemson University, USA

Equilibrium-thickness intergranular films (IGFs) have been widelyobserved in ceramics. Recently, metallic IGFs of similar characterhave been observed (Acta Mater. 2007, 55:3131) and bulk CAL-PHAD methods have been extended to quantitatively explain grainboundary (GB) disordering in binary alloys (APL 2008, 92:101902).In this study, temperature- and composition-dependent GB adsorp-tion and disordering in doped tungsten are characterized by Augerelectron spectroscopy and HRTEM using well-quenched specimens.Binary GB complexion (phase) diagrams are constructed. These sub-solidus quasi-liquid IGFs have broad technological implications inactivated sintering, grain growth, creep, liquid metal embrittlement,and other GB-controlled properties. Furthermore, these dopedtungsten alloys serve as relatively simple model systems for under-standing IGFs in ceramics, where the presence of London dispersionforces and electrostatic interactions should produce more complexinterfacial phenomena.

(FUND-025) Meshless Numerical Simulation of Stress-AssistedCrack Growth in a Brittle SolidZ. Tang*, G. Liu, Zhejiang Ocean University, China

The evolution of a crack-like defect that propagates by stress drivencorrosion in an isotropic, linear elastic solid is simulated by applyingMeshless Local Petrov-Galerkin (MLPG) method, where the MLPG5method has been adopted. Depending on material properties, load-ing, and temperature, three possible behaviors are observed for theflaw: (i) gross blunting at the crack tip; (ii) stable, quasi-steady statenotch-like growth; and (iii) unstable sharpening of the crack tip. Therange of material parameters and loadings that cause each type of be-havior is computed. The results confirm the existence of a thresholdstress level that leads to crack sharpening and ultimately to cata-strophic fracture.

(FUND-026) Development of a Polarizable, Variable ChargePotential for the Molecular Dynamics Simulation of Aluminum–Aluminum Oxide InterfacesB. D. Devine*, A. McGaughey, S. R. Phillpot, S. B. Sinnott, University ofFlorida, USA

Large scale molecular dynamics simulations of metal – metal oxideinterfaces provide tremendously valuable insight into the atomicscale processes that influence the form and function of compositenanostructures. The simultaneous simulation of a metal coupledwith its oxide requires at least a variable charge potential that de-scribes bonding in widely different electrostatic environments. Thiswork presents the development and application of a polarizablecharge transfer potential for simulations of the aluminum and alu-minum oxide interface. The potential is based on the embedded atommethod coupled with a variable charge electrostatic scheme. We havefound, however, that when applying such a potential to interfaces, in-clusion of polarization to at least the dipole moment is necessary tostabilize the alpha-alumina phase in both real and charge space. This

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 13

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania14

work is supported by the National Science Foundation (grant no.DMR-0426870).

(FUND-027) Computational Tools for the Design of Weldable andCreep Resistant SuperalloysF. Tancret*, Université de Nantes, France

One major drawback of many nickel-base superalloys is their poorweldability. In particular, cracking can occur during solidification, inthe so-called Brittle Temperature Range, or Brittleness TemperatureRange (BTR). Another type of cracking is due to the formation of liq-uid films in the heat affected zone (HAZ), by the liquation of lowmelting point phases like carbides or intermetallics. In this work,CALPHAD-type computing tools (Thermo-Calc, Dictra) are used topredict the occurrence of cracking, and to design Ni base alloys byminimizing both the BTR and the risk of γ’ liquation, while keeping agood phase stability and good mechanical properties in the expectedservice temperature range. Among others, the creep rupture resist-ance is estimated through the multivariate regression of existing data,using artificial neural networks or Gaussian processes. Predictions arefirst compared to data in the case of existing alloys, and then used topropose new weldable and heat-resistant superalloys.

(FUND-028) Investigating Predictive Capabilities of Image-basedModelling for Woven Composites in a Scalable ComputingEnvironmentJ. K. Farooqi*, F. C. Plaza, L. Margetts, M. A. Sheikh, P. Mummery, TheUniversity of Manchester, United Kingdom

This paper covers research on preparing best possible 3D compositematerial models that capture the complexity of woven textiles inthese Carbon-Carbon composites. X-ray microtomography has beenused for this purpose. Higher resolution models, necessary to estab-lish phase separation between constituents, form very large data setsthat have been accommodated in parallel-processing supercomput-ers. Basic stress/strain behaviour has been captured with due agree-ment with experimental results through in-situ measurement incompression tests. Mechanical strain measured through eitherprocess bears decent resemblance to the other, thus validating theimage-based modelling route for this and other future applications.

(FUND-029) 3D Phase Field Simulations of Grain Growth in ThinFilms: Pinning Effect of Second-Phase Particles and ThermalGroovingN. Moelans*, K.U.Leuven, Belgium

At elevated temperatures, where the mobility of the atoms is high,considerable grain growth and thermal grooving occurs in all poly-crystalline materials. Surface tension and thermal grooving have animportant effect on grain growth in thin films due to the high ratio ofsurface to bulk material. The thermal grooves have a pinning effect onthe grain boundaries and hinder normal grain growth. Furthermore,small particles or impurities that lead to the formation of small pre-cipitates are often added to thin films for extra pinning of the grainboundaries. Mostly the purpose is to induce abnormal grain growth(=secondary recrystallization) and, in this way obtain films with largecolumnar grains. A phase field model for grain growth that takes ac-count of the surface energy of the grains and the presence of second-phase particles is presented and simulation results are shown.

(FUND-030) Effect of Antimony Dopants on the PlasticDeformation Behavior of Single Crystal and Nanocrystalline CopperR. K. Rajgarhia*, D. E. Spearot, A. Saxena, University of Arkansas, USA

Molecular dynamics simulations have been used to study dislocationnucleation under constant tensile strain in single crystal andnanocrystalline copper with varying concentrations of antimony(0.0-2.0 at.%). In low concentrations, antimony does not form clus-ters or precipitates in copper and completely segregate to grainboundaries. Therefore for the initial configuration, antimony atomswere randomly distributed in the single crystal model. It was ob-served that the strained regions around the antimony atoms act as

sources for partial dislocations and the maximum stress decreasedwith the increasing concentration of antimony. In the nanocrystallinemodel, antimony atoms were preferentially located at grain bound-aries and the effect of grain size and antimony concentration will bediscussed. The ultimate goal is to understand the underlying mecha-nisms involved with plasticity in Cu-Sb to fabricate a Cu-Sbnanocrystalline alloy with superior mechanical properties.

(FUND-031) First-Principles Phonon and ThermodynamicProperties of Disordered Alloys: Application to the Ni-Pt SystemS. Shang*, Y. Wang, Z. Liu, Pennsylvania State University, USA

Besides the time-consuming first-principles molecular dynamics, thetreatment of temperature and disordering in first-principles calcula-tions is still a pending issue. In the present work, we aim to investigatethe thermodynamic properties of disordered alloys as a function ofcomposition and temperature, wherein (i) the disordering of compo-sition is described by both the special quasirandom structure (SQS)and the statistical approach of ordered structures; (ii) the tempera-ture effect is treated by the quasiharmonic approach starting fromfirst-principles phonon calculations. Using FCC-based Ni-Pt alloy asa prototype, we predict the first-principles phonon properties of thedisordered alloys based on the 8-atom and 16-atom SQSs as well asthe selected ordered structures, which are in good agreements withthe measurements. To the end, the finite-temperature thermody-namic properties of the Ni-Pt alloys have been calculated and com-pared with available experiments.

(FUND-032) Direct First-Principles Approach to the Order-Disorder TransitionY. Wang*, S. Shang, L. Chen, Z. Liu, Penn State, USA

A precise first-principles description of order-disorder phase transi-tion has been a challenge subject. In this study, an attempt is made tocreate a finite temperature framework for the order-disorder phasetransition within which all the input energies of the varieties of con-figurations are completely taken from the first-principles calculation.Cu-Au has chosen as the example. With three 12-atom supercells, wehave calculated the energies of 439 symmetrically nonequivalentstructures which are reduced from 3x4096 configurations. With thecalculated energies, we further build the partition function fromwhich all thermodynamic quantities can be derived.

(FUND-033) Corrosion behavior of SiC ceramics under HighTemperature Sulfuric Acid ConditionsC. Jung*, C. Park, J. Park, Korea Atomic Energy Research Institute, South Korea

IS (Iodine sulfur) process, a hydrogen production, is one of the candi-date process for using its high temperature energy of very high tem-perature gas cooled reactor (VHTR) in the nuclear power industries.The IS process is efficient and promise for a hydrogen production,however, the highly corrosive environment condition of this overallprocess limits an application of this process for H2 production.Therefore, the corrosion behavior of special materials was importantparameter for material’s integrity assessment Corrosion tests of SiCmaterials (RBSC and coated SiC on Ni based alloy) were performedin boiling 98wt% sulfuric acid solution. Corrosion rates were meas-ured by using the weight change. The surface morphologies were ex-amined by using SEM-EDS. A silicon oxide passive layer on SiC sur-face is attributable to a corrosion resistance for RBSC in boiling98wt% sulfuric acid.

(FUND-034) Cluster Variation Method in Defective SolidsD. S. Mebane*, Max Planck Institute for Solid State Research, Germany; J.Wang, National Chiao Tung University, Taiwan; M. Liu, Georgia Institute ofTechnology, USA

The cluster variation method (CVM) can be viewed as a first-orderimprovement over mean-field descriptions of lattice interactions. Atthe same time, it possesses a tractable, closed mathematical form thatmay make it easier to use than cluster expansion methods. This posterpresents the adaptation of CVM, which has been applied primarily in

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 14

Su

nd

ay P

M

www.matscitech.org 15

the realm of full-lattice, substitutional metal and oxide solutions, to aproblem involving a highly defective oxide lattice with short-rangeinteractions in the fluorite structure. Results are compared withMonte Carlo simulations.

(FUND-035) Effects of Inner Ag/Pd electrode on Microstructureand Resistivity of Cofired PZT-SKN Multilayer ActuatorsJ. Kim*, N. J. Donnelly, C. A. Randall, Center for Dielectric Studies, MaterialsResearch Institute, The Pennsylvania State University, USA

A lead zirconate titanate (PZT) ceramics incorporating the dopantsSr, K, and Nb (SKN) were co-fired with the inner Ag/Pd electrode andthe physical and electrical properties of PZT-SKN multilayer actua-tors were investigated. Also PZT-SKN multilayer actuators withoutthe inner electrode were prepared to examine the effects of the innerAg/Pd electrode on the properties of the multilayer actuators. Insula-tion resistance was considered under the time dependent conditionsat the elevated temperatures, and/or under the high humidity condi-tions. Relative changes in insulation resistance were measured withimpedance spectroscopy, and thermal stimulated current techniques.

(FUND-036) Measurement of Chemical Diffusivities of ProtonConductor OxidesJ. Kim*, H. Yoo, Seoul National University, South Korea

The electrical conductivity relaxation upon an abrupt change of, e.g.,oxygen activity of an oxide MO is normally monotonic and hence,often employed to determine the chemical diffusivity of the binaryoxide. For a ternary proton conductor oxide, however, the relaxationwith time appears nonmonotonic exhibiting a local extremum withtime, particularly upon abrupt change of water activity in fixed oxy-gen activity atmospheres. This unusual, nonmonotonic relaxation,that thus long remained unelucidated, has recently been solved ana-lytically in terms of two coupled chemical diffusion of H and O undertwo independent chemical driving forces. By applying the analytic so-lution, we have measured the four chemical diffusivities on the sys-tems of ACe0.95Yb0.05O3-δ(A=Ba, Sr) as functions of the activities ofH2O and O2, at different temperatures (600-900oC). We report thenumerical values for the chemical diffusivities, together with the ex-perimental details.

(FUND-037) Oxygen reduction kinetics of LSM model cathodes:partial pressure dependence and rate limiting stepsJ. Fleig*, Vienna University of Technology, Austria; K. Hae-Ryoung, MaxPlanck Institute for Solid State Research, Germany; J. Jamnik, NationalInstitute of Chemistry, Slovenia; J. Maier, Max Planck Institute for Solid StateResearch, Germany

Sr-doped LaMnO3 (LSM) thin film microelectrodes prepared byPLD and photolithography on yttria stabilized zirconia electrolytesare investigated by impedance spectroscopy. Oxygen partial pressure,microelectrode diameter and microelectrode thickness are varied inorder to achieve a mechanistic interpretation of the impedance spec-tra. By means of an equivalent circuit based on a continuum model aquantitative analysis of the spectra was possible and allowed a separa-tion of the resistances associated with oxygen exchange at the surfaceof the LSM electrodes and oxide ion transport through the thin filmelectrodes (bulk path of oxygen reduction). At low oxygen partialpressures the surface-related resistance is rate-limiting while on in-creasing partial pressure a change in the limiting step results. The ex-perimental data are used for calculating the polarization resistance ofoxygen reduction via bulk path in porous LSM electrodes.

(FUND-038) Point Defects and Cation Diffusion inCobaltorthosilicateQ. Tang*, R. Dieckmann, Cornell University, USA

A study of point defects and the diffusion of cobalt in cobaltorthosil-icate has been initiated. This study involves producing colbalt-or-thosilicate powder by a ceramic and by a sol-gel route, the growth ofsingle crystals with difgferent orientations by the floating zonemethod, thermogravimetric measurements on the variation of the

oxygen content and cobalt tracer diffusion experiments. First experi-mental results will be presented and discussed.

(FUND-039) Effects of Oxygen Vacancies on the DielectricRelaxation Behavior of Al-doped BaTiO3S. Lee*, Y. Han, Sungkyunkwan University, South Korea

Curie point (Tc) of Ba(Ti1-xAlx)O3-δ shifted to lower temperatures asAl content (x) was increased. At lower frequencies(<1 kHz), dielectricconstants steeply decreased with increasing frequency. At > 1kHz, di-electric constants blended into a simple line and became independentof Al-doping levels. Dielectric loss (tanδ) peaks moved to higher fre-quencies with increasing Al content (x) in the Ba(Ti1-xAlx)O3-δ system(0.0005 ≤ x ≤ 0.02) at 250oC. The activation energy was estimated tobe 0.42-0.65eV at 150~300oC and 0.90~1.06eV at 350~500oC. Theactivation energy at higher temperatures was due to the extra energyrequired for the dissociation of the defect complex (Al′Ti-VO

..) in ad-dition to the dipolar motion of oxygen vacancies. Second phases weredetected in the specimen doped with 2.0 mol% of Al. With increasingAl contents, the grain size decreased up to 1.0 mol% Al, whereas, asignificant change in grain size was observed with 2mol% Al.

(FUND-040) Grain Conductivity of Accepter or Donor-dopedPolycrystalline AlN CeramicsS. Lee*, H. Kim, Y. Oh, H. Kim, KICET(Korea Institute of CeramicEngineering & Technology), South Korea

Aluminum nitride ceramics is one of the widely adopted materials toguarantee the temperature uniformity in the wafer processing equip-ment in the semiconductor industry. To enhance the uniformity, thewafer is chucked tightly to the AlN ESC by applying high DC electricfield. In this study, electrical conductivity were investigated when ac-ceptor(Mg2+) or donor(Si4+) were doped to AlN ceramics sinteredat 1850 degree C with 1 wt% Y2O3. As Mg2+ were doped, the grainconductivity, which was separated using impedance spectroscopy, de-creased. DC conductivity measurement showed similar results, im-plying that the grain conductivity have significant effects on the DCconductivity

(FUND-042) Study of Properties in MgB2 Doped with CaB6 byHigh Energy Ball Mill (SPEX 8000D)Y. P. Cardona*, R. Perez, University of Puerto Rico in Mayaguez, USA; J. Silva,A. Rossa, O. Uwakweh, University of Puerto Rico, USA; E. E. Hellstrom, D. C.Larbalestier, Florida State University and the National High Magnetic FieldLaboratory , USA

The doping of magnesium diboride (MgB2) by the addition of cal-cium boride (CaB6) at 5 at% will be carried out by high-energy ballmilling at 300 minutes of milling. All the samples will be processed inSPEX 8000D followed by cold and hot isostatic pressing. The ob-tained samples will be characterized by measuring critical currentdensity (Jc) and critical temperature transition (Tc), while structuralcharacterization will be undertaken with X-ray diffraction and Scan-ning Electron Microscopy (SEM). The values of these properties willbe compared with the ones obtained in previous studies carried outon bulk and doped MgB2. In addition, doping with other transitionmetal diborides such as Titanium Diboride (TiB2), ChromiumBoride (CrB2) and Niobium Boride (NbB2) will be carried out. Theresults of this work will be an important contribution towards the de-velopment of improved superconductors with better Jc capable ofperforming at higher Tc.

(FUND-043) Fabrication and characterization of ZnO nanorodarrays and nanowires from aqueous solutionsY. Su*, Beijing Information Technology Institute, China

We are reporting here on an inexpensive and fast fabrication methodfor ZnO nanorod arrays and nanowires in aqueous solutions. Thesynthesis involves a template-less, surfactant-free and moderate tem-peratures aqueous method with controlled complexity. It enable eas-ily obtained arrayed ZnO nanorods and nanowires on various sub-strates from an aqueous solution of zinc salt, and the obtained ZnO

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 15

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania16

nanorods are uniformly distributed on the surface of substrates. Itenables the control of the size of nano-, meso-, and microcrystallites.Process parameters such as concentration, temperature and time,type of substrate are critical for the growth of nanorod arrays withthin diameter. We use X-ray diffraction, scanning electron mi-croscopy, energy dispersive spectroscopy and transmission electronmicroscopy to characterize the morphology and microstructure ofthe arrayed ZnO nanorods and nanowires.

(FUND-044) Statistical Analysis: Effect of Boron in Al-SiComposites Under Different Types of CastingsA. Cintron-Aponte*, O. Suarez, J. Gonzalez, L. Principe, University of PuertoRico, Mayaguez, USA

In the aerospace industry Al-Si alloys have multiple applications be-cause of their attractive mechanical properties and low density. Thiswork discusses the effect of diboride particles in the mechanicalproperties of an Al-Si composite manufactured via different types ofcasting to compare them to gravity and centrifugal casting. Charac-terization techniques include hardness testing, tension testing anddistance between reinforcement particles. These techniques will beunder study with via a 2k design of experiment and statistical analy-sis. The interaction of those factors will be of particular interest dueto its impact on the final properties of the composite.

(FUND-045) Phase Constituents and Microstructure of TernaryUranium-Alloys and Their Interdiffusion with AlA. Ewh*, University of Central Florida, USA; D. D. Keiser, Idaho NationalLaboratory, USA; Y. Sohn, University of Central Florida, USA

Uranium-based metallic nuclear fuels are being developed for re-search reactors with low-enrichment. In this study, we have examinedthe phase constituents and microstructure of four ternary alloys, U-10Nb-4Zr, U-8Mo-3Nb, U-7Mo-6Zr, and U-7Mo-3Ti (wt.%) thatwere arc-melted and homogenized at 950°C for 96 hours. X-ray dif-fraction, scanning electron microscopy with X-ray energy dispersivespectroscopy, and transmission electron microscopy via focused ionbeam in-situ lift-out was employed to observe the equilibrium phaseconstituents and their microstructure. Interdiffusion behavior ofthese ternary alloys against Al was also examined with solid-to-soliddiffusion couples annealed at 600°C for 10 hours. Phase constituentsand growth kinetics of reactive diffusion layer, that primarily con-sisted of various aluminides were determined for four ternary alloyswith respect to polymorphic stability of U-alloys.

(FUND-046) Effect of Heat Treatment on Aluminum Boron SiliconCompositesC. F. Benitez*, university of puerto rico at mayaguez, USA; O. Suarez,University of puerto rico mayaguez campus, USA

Aluminum boride reinforces can improve aluminum matrix compos-ites intended for aerospace components and applications. This re-search compares the effect of melt treatments on AlB12 particlespresent in Al-B-Si composites and the resulting mechanical proper-ties of those composites. Melt treatment of semisolid composites con-taining 0- 2 wt.% Si allowed studying the kinetics of the AlB12 trans-formation in the presence of Si in the melt (0% Si was used as controlsample). Characterization techniques used included optical mi-croscopy, x-ray diffraction, scanning electron microscopy (SEM),Charpy impact test and quantitative metallography. Our resultsshowed that silicon stabilizes AlB12. Al-B-Si samples are more brittlecompared to Al-B samples. The results provides alternative means toimprove ductility in Al matrix composites.

(FUND-047) Growth Mechanisms of Fine and Coarse Precipitatesin the Superalloy IN738LCD. Erdeniz*, E. Balikci, Bogazici University, Turkey

IN738LC is a polycrystalline, nickel-base superalloy, which provideshigh performance in aggressive environments at temperatures above650°C. Some of the expected properties are corrosion resistance,creep and fatigue resistance. These required properties are obtained

via solid solution hardening and precipitation hardening of face-cen-tered cubic (fcc) Ni matrix phase. The size, morphology, and distri-bution of precipitates determine the properties of the material. Thus,microstructure control is extremely important for effective use ofIN738LC. In this study, aging treatments at 950°C and 1120°C werecarried out from 1 hour up to 480 hours. Microstructural evolutionmechanisms of fine and coarse precipitates were discussed separately.It was observed that precipitates were growing via solute absorptionfrom the matrix or merging with adjacent ones. The results showedthat fine precipitates grow faster than coarse ones, but 480 hours werenot sufficient to obtain a unimodal microstructure at 950 °C.

(FUND-048) Athermal Martensitic Transformation in YttriaDoped ZirconiaJ. Pee*, Y. Kim, H. Kim, E. Choi, KICET, South Korea

A metastable tetragonal phase could be obtained at room tempera-ture by rapid cooling of the high temperature cubic phase zirconiadoped with low contents yttria. The metastable tetragonal phasereadily transformed into the stable monoclinic phase by heating ataround 500K. More interestingly, the metastable tetragonal phase un-derwent a burst-type martensitic transformation into the monoclinicphase during a subzero cooling to the liquid nitrogen temperature.The occurrence of both isothermal and athermal transformations inthe sample of the same chemical composition is very rare. In thispaper, the kinetics of athermal transformation was studied with spe-cial interests in its dependence on the composition, grain size andaging treatment. Metastable tetragonal phase of zirconia doped with1.40~1.60mol% of yttria exhibited a burst-type martensitic transfor-mation at subzero temperatures. The burst temperature strongly de-pended on yttria content and grain size.

(FUND-049) Thermal Characterization of a Metastable AluminumBoridesJ. Torres*, J. R. Vazquez, O. Suarez, University of Puerto Rico, MayaguezCampus, USA

The main goal of this research has been to thoroughly investigate thismetastable dodecaboride in order to predict its behavior under a widerange of temperatures. Preliminary experiments allowed determiningthe time necessary for the decomposition of AlB12 to AlB2 at 650°C.After determining the time needed for the reaction to occur, a seriesof heat treatments were devised to pinpoint the minimum tempera-ture at which this phase transformation occurs in the solid state. Thesamples were obtained via gravity casting. The microstructures wereanalyzed using optical microscopy and Scanning Electron Mi-croscopy (SEM) in backscattered electron mode. The samples werecompared with X-Ray Diffraction (XRD) standards produced withAlB2 and AlB12. The heat treatments demonstrated that the destabi-lization occurs at a faster rate when the temperature is close to 650°C.This research is sponsored by the National Science Foundation underGrant No. 0351449 (PREM Program).

(FUND-050) Effect of Stress on the High TemperatureMicrostructural Stability of γγ-TiAl alloysK. Subramanian*, R. Babu, Indian Institute of Science, India

The microstructural stability of duplex and fully lamellar γ-TiAl al-loys was studied under thermal exposure and creep conditions. Themicrostructure of exposed and tertiary-crept samples was character-ized using SEM-EBSD and TEM. Loss of excess α2 and precipitationof B2 were observed in thermally exposed samples. On the applica-tion of stress, the duplex alloy exhibited dynamic recrystallization,the extent of which depended on the creep strain. In crept samples ofthe fully lamellar alloy, loss of α2 and the lamellar structure were ob-served in addition to dynamic recrystallization. Stabilizing the mi-crostructure before loading significantly depresses tertiary creep, im-plying that retention of excess α2 is the primary cause of loss oflamellar microstructure. Microstructural degradation and tertiarycreep behavior are different under tension and compression under-

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 16

Su

nd

ay P

M

www.matscitech.org 17

scoring the role of the transformation strains (associated with α2 dis-solution) in dictating microstructural evolution under stress.

(FUND-051) Phase studies of the Fe3PO7 -FePO4 systemL. Zhang*, M. E. Schlesinger, R. K. Brow, UMR, USA

The phase equilibria of Fe2O3 –FePO4 system have been investigatedusing DTA and TGA. The decomposition of Fe3PO7, iron reductionand liquidus surface in the system were studied using SEM-EDS sys-tem and X-ray diffraction on a series of quenched samples. The re-sults show that Fe3PO7 decomposes to solid Fe2O3 and a liquid at tem-perature higher than 1090±10°C. Iron reduction is an endothermicprocess, which prefers the direction to reduced state at high tempera-ture. The enthalpy changes were calculated and discussed for iron re-duction in Fe3PO7 and that in FePO4. Finally, phase diagram has beenmodified and discussed based on the combination of DTA and SEM-EDS. The eutectic composition of Fe3PO7-FePO4 system is at 42.5 wt-% Fe and eutectic temperature is 1070±10°C.

(FUND-052) First-Principles Calculation of Diffusion CoefficientsM. Mantina*, Y. Wang, S. Shang, L. Chen, Z. Liu, Pennsylvania StateUniversity, USA

We report diffusion coefficients in metals and dilute alloys from anentirely first-principles-based procedure. In particular, the diffusionprefactor and activation energy of self-diffusion and solute diffusionof normal elements and 3d transition elements in Al are presented asa function of temperature. Excellent match of diffusivities with ex-periments is attained. Application to diffusion of rare earth solutes inmagnetic and non-magnetic host elements will be discussed. Extend-ing the ab-initio approach to concentrated solutions is also underconsideration.

(FUND-053) Critical Evaluation and Thermodynamic Modeling ofthe Mg-Mn, Al-Mn and Mg-Al-Mn systemsM. A. Khan*, M. Medraj, Concordia University, Canada

A self-consistent thermodynamic description of the ternary Mg-Al-Mn system has been developed using the modified quasichemicalmodel for the liquid phases, random solution model for the terminalsolid solutions and the compound energy formalism for the interme-diate solid solution phases. The thermodynamic descriptions of thebinary sub-systems are assessed and combined to calculate the ter-nary Mg-Al-Mn system. Only one composition dependent ternaryparameter has been used to describe the ternary liquid phase. All theavailable experimental phase diagram and thermodynamic informa-tion in the literature have been evaluated and compared with the cur-rent results. The optimized parameters of the present assessment canreproduce the experimental data within the experimental error limit.The ternary database thus forms the basis for the design of experi-ments and the subsequent update with the availability of new experi-mental data.

(FUND-054) Phase separation in Sr1-xBaxSO4 solid solution byHydrothermal SynthesisR. Suarez-Orduña*, L. P. Rivas-Vázquez, Universidad del Papaloapan,Mexico; J. C. Rendon-Angeles, Centro de Investigación y de EstudiosAvanzados del IPN, Unidad Saltillo, Mexico; K. Yamagisawa, ResearchLaboratory of Hydrothermal Chemistry, Kochi Universityy , Japan

The phase stability of the Sr1-xBaxSO4 solid solution during the ex-change reaction of SO4

2- ions with CO32- ions in barium strontium

sulfate solid solution under hydrothermal conditions was investi-gated. The Experiments were performed at several temperaturesranging from 423 to 523 K for different reaction times between 1 and96. Structural characterization of partially and completely convertedSrCO3 crystals was conducted by XRD, FTIR, ICP and SEM. Underhydrothermal conditions, it was observed that the Ba2+ ions wereeliminated from the solid solution structure (Sr1-xBaxSO4). Accordingto the obtained results, the reaction occurs in a two stage process: thefirst stage was a surface dissolution of the solid solution Sr1-xBaxSO4,and the subsequent precipitation of the Sr1-xBaxCO3. The last stage to

obtain the SrCO3 phase, free of impurities consists in dissolution –recristallization mechanism with the Barium release, due to the low-est stability of the Ba2+ ion under hydrothermal conditions.

(FUND-055) Thermodynamic Model of the Mg-Ca-Zn SystemS. W. Rahman*, M. Medraj, Concordia University, Canada

A thermodynamic description of the ternary Mg-Ca-Zn system hasbeen developed as a part of a multicomponent thermodynamic data-base for Mg alloys that includes most of the important alloying ele-ments. The available thermodynamic and phase diagram data werecritically evaluated for the binary subsystems. Optimized thermody-namic properties of the binary systems were then used to model theternary system. The literature included contradicting information re-garding the ternary compounds in this system. Therefore thermody-namic modeling of phase equilibria was used to determine the mostlikely description of this system and to exclude the self-contradictingexperimental observations. The liquid phase was described by themodified quasichemical model while the intermediate solid solutionswere modeled with the compound energy formalism. The resultingmodel predicted 7 saddle, 10 quasi-peritectic, 3 peritectic and 5 ter-nary eutectic points. The calculated results were found in accord withthe available experimental data in the literature.

(FUND-056) Deformation Mechanisms and Phase Stability in LowModulus ββ-Ti AlloysS. Rajagopalan*, The Ohio State University, USA; Y. Murayama, NiigataInstitute of Technology, Japan; S. Nag, R. Banerjee, University of North Texas,USA; G. Viswanathan, H. L. Fraser, The Ohio State University, USA

Low modulus β-Ti alloys exhibit several attractive properties, partic-ularly suited for biomedical applications. This work examines thephase stability in candidate low modulus alloys based on Ti-Nb-Zr-Ta, Ti-Cr-Sn and Ti-Cr-Zr-Sn systems. The effect of varying alloycomposition on the observed microstructure and the consequent de-formation mechanisms is addressed. Of particular interest are the keyparameters differentiating twinning and deformation by slip, and therole of the omega phase in the deformation process. The effect ofthermal history on the macroscopic mechanical properties is dis-cussed. Finally, an attempt is made to provide a mechanistic under-standing of the key processes governing the transition in deformationmodes with varying β-stabilizer content.

(FUND-057) Investigation of Brazing Steel Sheets forLaminated ToolsX. Wu*, Wayne State University, USA; M. Lowney, Fast4m, USA

Three-dimensional forming dies can be manufactured by brazinglaser-trimmed steel sheets to near-net-shape, and the new process al-lows significant reduction of tool lead-time and achieve internalcooling at high cooling rate and with desired temperature distribu-tion, being important for enhancing productivity and quality. Inorder to increase the brazing strength, different copper-based brazingalloys and under different brasing conditions are studied extensively.The ultimate tensile strength of round samples with the bonded lam-inates perpendicular to the tensile axis has reached up to 95% of thebase steel. SEM examination and chemical analysis indicate that in-terface reaction and interdiffusion control is critical factor for achiev-ing a high brasing strength

(FUND-058) Compressive Deformation Behavior of HighTemperature Mo-Si-B AlloyX. Wen*, University of Cincinnati, USA; P. Jain, Brown University, USA; J.Schneibel, Oak Ridge National Laboratory, USA; K. Kumar, BrownUniversity, USA; V. K. Vasudevan, University of Cincinnati, USA

Alloys based on Mo-Si-B ternary system are of interest for very hightemperature structural applications. The compression behavior at1200, 1300 and 1400°C of a nominally Mo-20Si-10B (in wt.%) alloythat was processed such as to yield varying α-Mo volume fractions

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 17

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania18

(from 5 to 46%), with the balance made up of Mo3Si and T2-Mo5SiB2 phases, was studied. The results of constant strain rate com-pression tests showed that the stresses required to maintain a givenstrain rate increased with a decrease in temperature and decreasedwith an increase in the α-Mo volume fraction at any given tempera-ture. The values of the stress exponents determined from the dataranged from ~3-9, depending on temperature and volume fractionof α-Mo; the activation energy for creep was found to be in the rangeof ~200-600 kJ/mole depending on stress level and volume fractionof α-Mo. These results were correlated with SEM and TEM observa-tions of the damage processes, deformation structures and deforma-tion mechanisms.

(FUND-059) Electron Microscopy Observation of R5(Si,Ge)4 AlloysZ. Qian*, L. Chumbley, Iowa State University, USA

Optical and electron micrographs reveal that R5(Si,Ge)3 type com-pounds, existing as thin plates, are prevalent in R5(Si,Ge)4 com-pound systems (R equals a lanthanide element). The purpose of thisresearch is an attempt to better understand the formation of thesethin plates by extending microstructural examination to otherR5(Si,Ge)4 systems where R5(Si,Ge)3 compounds are less likely toform. Ho, Yb alloys and Sb, Ga, Sn substituted compounds were ex-amined by X-ray powder diffraction (XRD), scanning electron mi-croscopy (SEM) and energy dispersive spectroscopy (EDS). Thinplates of R5(Si,Ge)3 type compounds were observed in the Ho andYb based systems and Sn compounds but not in alloys where Sb or Gawas substituted for Ge/Si. The absence of plates in the Sb/Ga-substi-tuted alloys is related to the deviation of the lattice matching condi-tion and the valence electron concentration from the conventionalR5(Si,Ge)4 systems.

(FUND-060) Amorphous Orientation and Its Relationship toProcessing Stages of Blended Polypropylene/Polyethylene FibersA. Trottier*, J. W. Zwanziger, Dalhousie University, Canada

Changes in the molecular orientation, melting behavior, and percentcrystallinity of the individual components in a fibrous blend of iso-tactic polypropylene (iPP) and high-density polyethylene (HDPE)that occur during the melt extrusion process were examined usingwide-angle X-ray diffraction (WAXD) and differential scanningcalorimetry (DSC). The crystalline orientation of each componentwas found using Wilchinsky’s treatment of uniaxial orientation anddescribed by the Hermans–Stein orientation parameter. The amor-phous orientation was found by resolving the X-ray diffraction pat-tern in steps of the azimuthal angle into its iPP and HDPE crystallineand amorphous reflections. This work demonstrates how WAXD canbe used as a standalone technique to determine the amorphous orien-tation of individual components within an immiscible semicrystallineblend. The utility of DSC and WAXD analyses to capture the effects ofsmall differences in processing, and the use of these results as finger-prints of a particular manufacturing process were demonstrated.

(FUND-061) Synthesis of straight Y-shaped silica nanorodsG. Zhu*, Beijing Information Technology Institute, China

A simple method is presented for the synthesis of straight Y-shapedsilica nanorods with a diameter of about 50-200nm with smooth sur-face. The Y-shaped silica nanorods were synthesized by thermalchemical evaporation method. The synthesized samples were charac-terized by means of scanning electron microscopy, transmission elec-tron microscopy. The results suggested that the growth of such silicananorods may be a result of the fluctuation of external conditionscausing a change in the growth direction of silica nanorods devel-oped. The present method can easily be synthesized different struc-ture production for a wide variety of applications.

(FUND-062) Synthesis of Flower-like Silica NanowiresG. Zhu*, Beijing Information Technology Institute, China

A novel flower-like silica nanowires was synthesized by using siliconand silica mixed powder as Si source using thermal evaporation

method. The as-grown product was characterized by scanning elec-tron microscopy, transmission electron microscopy, energy-disper-sive X-ray spectroscopy. The results indicated silica nanowires had aflower-like microstructure with smooth surface, and had no metalcontaminations. A possible growth model based on vapor–solidmechanism is suggested.

(FUND-063) Microstructural Changes of the Plasma ResistantCeramics during the Exposure to CF4-O2 PlasmaS. Lee, Y. Oh, D. Kim, H. Kim*, KICET(Korea Institute of CeramicEngineering & Technology), South Korea

Ceramics are widely adopted as the plasma resistant materials in thewafer processing equipment in the semiconductor industry. However,the microstructural changes during the exposure to plasma were notclearly understood yet. In this study, we observed the microstructuresof Al2O3, Y2O3 and amorphous quartz after they were treated in theCF4-O2 plasma using the dual frequency etcher. Al2O3 grains wereinitially pulled out and then severely eroded producing many parti-cles. A typical plasma resistant material, Y2O3, showed local sphericalerosion of sub-micron size with nano-sized F-containing particle onthe eroded surface. On the other hand, amorphous quartz exhibiteduniform etching profile without localized erosion. In addition, etchrate and roughness changes were measured to evaluate the plasma re-sistances of the materials.

(FUND-065) Characterization of Al-Cu Alloys Reinforced withDodecaboridesM. Cruz*, C. S. Principe, A. Rodriguez, L. Olaya, O. M. Suarez, University ofPuerto Rico, USA

Aluminum matrix composites (AMCs) have proven success in struc-tural and aeronautical applications for their strength and lightweight. Therefore, careful characterization of their phase transforma-tions upon processing and resulting mechanical properties is essen-tial. In the present work aluminum alloys reinforced with AlB12 parti-cles were fabricated via gravity casting. The specimens wereheat-treated and analyzed using optical microscopy, Vickers micro-hardness, high temperature X-ray diffraction and differential thermalanalysis. The overall results demonstrated the metastability of AlB12dispersoids in contact with liquid aluminum and the subsequentchange of the dodecaboride into smaller AlB2 particles. Also an in-crease of the Al2Cu phase was observed for various heat treatments.

(FUND-066) A method for life assessment of Ni-base superalloyS. Farahany*, M. Aghaie-khafri, K.N.T University, Iran

In order to determine the remaining life of service exposed turbineblades it is necessary to characterize the degeneration of the mi-crostructure of the base metal during service. We selected RENE-80and IN-738 used in jet turbine blades.The material was produced byvacuum melting process. Samples with a size of 10mm × 10mm ×70mm were prepared from the material and then subjected to thestandard heat treatment and then specimens subjected to the ther-mally exposure at 800,850 and 900°C for 1000hr.Test specimens forcreep tests were prepared from the heat treated and aged materials ac-cording to the ASTM-E139. Creep and microhardness results com-pared with change of electrical conductivity. Experimental observa-tion showed increase of conductivity versus of decrease of life ofturbine blades. We suggested these physical properties for assessmentof materials; especially superalloys and it is a relatively simple tech-nique that fulfils all requirements.

(FUND-067) Thermophysical properties and microstructuralanalysis of AZ80 magnesium alloys designed for automotiveindustryG. Popescu*, P. Moldovan, S. D. Bejan, M. Manea, Politehnica University ofBucharest, Romania

Magnesium and its alloys are considered to be the lightest metalsavailable and are of major interest in automotive industry due totheir advantage in component’s weight reducing. Thermophysical

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 18

Su

nd

ay P

M

www.matscitech.org 19

properties of AZ80 plastic magnesium alloy are determined. Atdifferent dimensions (φ 5 mm and φ 28mm) and states (F and T5)are determined: the variation of diffusivity (α), the variation ofthermal expansion coefficient and its mean values in the sametemperature interval (60 – 400 C degrees). The microstructuralanalysis is determined by optical microscopy, SEM and EDS mi-croanalysis for two different bars of AZ80 alloy and presents a se-ries of continuous rows precipitates or poliedrical particles con-taining Mg, Al, Si and Ca. Knowing the density of AZ80 and usingthe obtained results it can be determined the thermal conuctivity(λ) of the alloy.

(FUND-068) Microstructures of aluminum alloy compositesmanufactured by liquid state methodsG. Popescu*, C. Popescu, P. Moldovan, S. Bejan, A. Buzaianu, Unversity “PO-LITEHNICA” of Bucharest, Romania

Composite materials with AlSi alloy matrix and Al2O3 particles as re-inforcements were prepared by vortex technique using different vol-ume fractions (5, 10, 15 and 20 vol.%). The obtained composites werepressed into a metallic mould, which was pre-heat before pressing,leading in principal to a controlled solidification of composites. Forthe corresponding composites were realized macro and microanaly-sis. Macro analysis put in evidence an increased porosity in the upperpart of samples which was induced by the samples cooling. Micro-analysis were done using SEI and BSE microscopy. They put in evi-dence the presence of silicon phase around the Al2O3 particles, thesize and distribution of Al2O3 particles, as well as the MgAl2O3spinel at the interface.

(FUND-069) Grain Refinement Techniques in γγ-TiAl Alloys inNano- and Micrometer ScalesH. Bahmanpour*, Wayne State University, USA; S. Heshmatimanesh, M. NiliAhmadabadi, H. Ghasemiarmaki, University of Tehran, Iran

In this paper, grain refinement of intermetallic alloys based on γ-TiAl through powder metallurgy and ingot metallurgy routes wasinvestigated. High energy ball milling was used to produce nanosized Ti-Al elemental powder mixture with a composition of Ti-48Al. Further heat treatment and consolidation of the milling prod-uct resulted in a very fine grained structure consisted of α2 and γphases. Also, effect of Cr, Si and Nb on phase transformations ofTiAl-based alloys and their further effect on grain refinement inmicro scale via ingot metallurgy routes was studied. Heat treatmentand thermomechanical processing were employed to study the effectof alloying elements and pre-forging microstructures on grain re-finement. Massive and feathery gamma as non-equilibrium prod-ucts of alpha phase decomposition obtained during rapid coolingwere found to be suitable starting microstructures for isothermalforging which give rise to a very fine grained microstructure ingamma alloys.

(FUND-070) Microstructure-Properties Relationship ofAluminum Alloys Inoculated with Nanosized BoridesH. E. Calderón*, University of Puerto Rico - Mayaguez Campus, USA; C.Smith, Austin College, USA; O. Menéndez, O. Suárez, University of PuertoRico - Mayaguez Campus, USA

The effect of nanosized MgB2, AlB2, HfB2, and NbB2 particles on thegrain structure and microhardness of AA6061 and AA7075 alu-minum alloys was studied. The metal boride powders were processedwith a vario-planetary ball milling unit to be afterwards mixed withpure aluminum pellets. The resulting mechanical mixtures wereadded as inoculant to the aforementioned alloys. For comparison thealloys were separately treated with a commercial grain refiner.Changes in grain size were observed: while boride-treated AA7075presented a dendritic structure, the boride-inoculated AA6061 alloyexhibited more equiaxed grain structure. Vickers microhardness testsshowed that MgB2 and HfB2 were most effective in improving me-chanical strength of these commercial aluminum alloys.

(FUND-071) Characterization of Brake Pads MaterialsDevelopment for Light Rail Transit ApplicationM. N. Berhan*, D. G. Solomon, Universiti Teknologi Mara, Malaysia

Friction process is needed in light rail transit braking system to decel-erate the vehicle for stopping purpose. This is achieved by tranform-ing kinetic energy of the vehicle to heat, via friction and dissipatingthat heat to the surroundings. The momentum absorbed by the brakepad during braking will increase the surface temperature. The in-crease of surface temperature will reduce the hardness of the brakepad. In this study the newly developed brake pad materials with dif-ferent formulation were characterized to determine their propertiessuch as thermal, chemical, mechanical and microstures.The final bestformulation was selected based on these different characterizationprocedures. The results are discussed in the light of characterizationand properties developed.

(FUND-072) Meso-Scale Simulation of the Shock-CompressionResponse of Ni+Al Powder Mixtures Using Real MicrostructuresD. E. Eakins, P. Specht, K. Johnson, N. Thadhani*, Georgia Tech, USA

Meso-scale simulations of the shock-compression response of Ni+Alpowder mixtures have been performed to investigate the influence ofparticle configuration on deformation and mass mixing, leading toshock-induced chemical reactions. Microstructures constructed fromSEM montages of Ni+Al powders pre-pressed at various densitites,were discretized and imported into CTH software. Travel of the shockwave was used to determine the equation-of-state of the mixture, andcompare with real-time measurements for validation. Observationsof particle-level processes were used to understand the macro- andmeso-scale effects exhibited as a function of particle morphology andporosity, and dis-similarities in properties of the constituents. Resultsrevealing the effects of particle heterogeneity on physical, chemical,and micromechanical response of shock-compressed powder mix-tures, and their role in shock-initiation of chemical reactions will bedescribed in this presentation.

(IRON-001) Effect of Al-Killed Steel Making Practices on InclusionContent: Implementation of Benchmarking for Improved ProcessControlT. J. Drake*, Aspex Corporation, USA

An aluminum deoxidation process for producing special bar qualitysteel was investigated to reveal various events that can lead to castabil-ity issues. To fully understand these effects, the authors have evalu-ated the inclusion content utilizing a high-throughput particle andinclusion characterization analyzer (PICA) which provides the size,shape, and elemental composition of all inclusions in a 50 mm2 areaof lollipop samples from both the ladle and tundish. Based on morethan 30 heats, it was concluded that the major portion of inclusionsconsisted of calcium aluminate and spinel complexes. In addition,CaS inclusions were prevelent. Through basic comparative studies,the hardware of the facility could handle a significant amount of non-liquid (>60%) inclusions without signs of castability issues. In addi-tion, the source of casting problems was coorelated to both ladlepractices and reoxidation events occurring in-line of the process.

(IRON-002) Effect of Processing Conditions on Decarburizationin the RH ProcessY. Kim*, K. Yi, Seoul National University, South Korea

In order to evaluate the efficiency of decarburization, various factorsmust be taken into account, pertaining to both geometry and pro-cessing parameters. Among these variables, the ones related to pro-cessing include as circulating gas flow, vacuum chamber pressure, ini-tial oxygen and carbon concentrations, amount of melt andprocessing time. These variables affect not only the flow patterns ofmixing, but also the reaction regions, making it difficult to analyzetheir influence. Moreover, each variable influences the system in anon-linear way, making it impossible to analyze them independently.In this study, we utilize a numerical simulation model developed to

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 19

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania20

analyze the RH process. The impact of each of the processing vari-ables are analyzed quantitatively through orthogonically-arrangedexperimentation, and ideal decarburization variable conditions areproposed by determining proximity to an equilibrium state.

(IRON-003) Multi-phase field simulation during austenite-ferritetransformationJ. Kim*, Kookmin Univ., South Korea; S. Kim, Kunsan Univ., South Korea;W. Kim, Chongju Univ., South Korea; S. Park, P. Kim, Kookmin Univ.,South Korea

Many theoretical and Experimental studies of austenite transforma-tion have been done during last century. In this study, we propose thephase field model to describe austenite-ferrite transformation inpolycrystalline materials. The developed model can use existing ther-modynamic databases, such as calpad, by changing thermodynamicdatabase to chemical potential forms. The developed model can treatinterface mobility exactly and can satisfy mechanical equilibrium attriple junctions. During austenite-ferrite transformation, transfor-mation stress evolution due to phase transformation and plastic de-formation during transformation plays an important role in growthferrite phase. We developed a very efficient elasto-plastic phase fieldmodel which can obtain the elastic-plastic solution in an inhomoge-neous system. Through various numerical simulations, we predicttransformation kinetics in various systems and we can find effect ofvarious factors.

(IRON-004) Microstructure and Mechanical Properties of aEutectoid FeNiMnAl AlloyY. Liao*, I. Baker, Dartmouth College, USA

The microstructure and mechanical properties of a novel eutectoidalloy with the composition (in at.%) of Fe-20Ni-35Mn-15Al havebeen studied. The alloy was arc melted from elemental powders, andSEM/EDS and TEM/EDS were used to determine the microstructuresand compositions of the phases present. The results revealed that thecompound was composed of FCC and B2 lamellae, whose widthswere ~300 nm and ~200 nm, respectively. Straining under compres-sion produced yield strengths ranging from 750 MPa at 300 K to160MPa at 1000K, with a rapid drop in yield strength at ~600K. Elon-gations of ~8% were observed in tensile tests at room temperature,with fracture surface analysis indicating a ductile fracture mode. Thedislocation behavior was also investigated. Research supported byNSF grant DMR-0505774.

(IRON-005) Development of 1MW arc plasma system for lowcarbon process of iron productionD. Kim*, J. Hong, B. Chung, J. Jeon, K. Lee, KAPRA, South Korea

1 MW power generating system and arc plasma torch for low carbonprocess of iron production have been developed. Electric power gen-erating system consists of 3 phase 380 V AC generator, voltage trans-former, inductors and rectifying circuit. For direct reduction of ironoxide, mixed gas of hydrogen and methane is used as plasma forminggas. Carbon rods are used as electrode material, and each terminal ofthree phase A.C. power supply is connected with a carbon rod. Threecarbon electrodes are in contact with each other and arc discharge issustained among the electrodes. Reactor for iron reduction is alsoconstructed using refractory materials. Plasma gas is injected fromthe bottom of furnace, and the exhausted gas flow is upward. Cen-trifugal pump for gas exhaustion and water jacket for off-gas coolingare located in the middle of exhausting conduit. Electric power con-sumption and carbon dioxide exhaust rate for iron production arecompared with conventional process.

(IRON-006) effect of temperature and atmosphere on theprecipitates distribution of Fe-3%SiE. Choi*, J. Yim, Y. Yoon, Y. Joo, Seoul national university, South Korea

Fe-3%Si steel which has superior magnetic properties is used astransformer core materials. To improve its magnetic flux density, thedevelopment of large grain with GOSS ({110}<001>) texture is re-

quired. This can be achieved by the abnormal grain growth duringsecondary recrystallization annealing. Precipitates play importantrole in this process. We have studied the evolution of the precipitatesin Fe-3%Si steel annealed at different annealing atmospheres. Thedistribution of precipitates on grain boundaries with respect to sizewas investigated by High Angle Annular Dark Field image of STEM,and the chemical analysis was performed with EDX. Annealing wasperformed in 25%N2-75%H2 condition as well as 100%H2. For25%N2-75%H2 annealing, small size precipitates are increased at800~900°C. The Precipitates are mostly composed with the multi-phase of AlN and MnS. The differences of precipitates in H2 anneal-ing are analyzed as well and their role for abnormal grain growth isdiscussed.

(IRON-009) Influential Factors on the Superfinished SurfacesR. D. Ionescu*, D. Amarandei, Stefan cel Mare University, Romania

The goal of this study was to identify the main influential factors thatreflect on the quality of surfaces of cylindrical steel pieces that under-went superfinishing in abrasive processes. The pieces were finishedwith the help of a Supfina device. We used fractional experimentplans, the analysis of variance and mathematical matriceal model,within the Taguchi method. Experiments were performed in order toclarify the influence on the quality of finished pieces of speed, feed,pressure and oscillation frequency of the tool, certain characteristicsof the abrasive tool, the initial quality of the piece surface. The exper-iments led to individual dependence relations, eventually the authorsare in a position to propose an exponential analytical model typeR=f(a,b,c,d,e,f), a relation that aptly captures the dependence ofroughness values on the surface for different combinations of the in-fluent factors we mentioned above. The relation applies for optimiza-tion of roughness in superfinished surfaces.

(IRON-010) Effects of Heat Treatment Parameters on theMicrostructure and Tensile Property for Q&P, AM and HardBainite SteelsS. Byun*, J. Jin, Pusan National University, South Korea; C. Oh, KoreaInstitute of Materials Science(KIMS), South Korea; N. Kang, K. Cho, PusanNational University, South Korea

High-strength steels have been developed for automotive suspensionapplications. Specifically, TRIP-aided steels have been focused due tothe hard-phase matrix for high strength and the retained austenite forstrain hardening. The hard matrix consists of martensite, annealedmartensite, and bainitic ferrite. Quenching and partitioning (Q&P),annealed martensite (AM) and hard bainite (HB) steels possess twocriteria of the retained austenite; blocky type and thin plate-like typecontribute the tensile property as a different manner. This study in-vestigated the effects of heat treatment parameters on retainedaustenite characteristics and mechanical properties for 0.24C steel.Tensile properties were discussed by matrix structure, fraction of re-tained austenite, its shape and stability.

(IRON-011) Galvanizing of TRIP-assisted Steels: MechanicalProperties and Reactive WettingE. M. Bellhouse*, J. R. McDermid, McMaster University, Canada

Galvanizing of transformation induced plasticity (TRIP)-assistedsteels can be difficult due to the two stage thermal cycle required toobtain the desired ferrite/bainite/retained austenite microstructureand the selective oxidation of the alloying elements Mn, Si and Al thatcan result in poor reactive wetting during galvanizing. Heat treat-ments were performed on a high Al – low Si TRIP-assisted steel withhigher than nominal bainite hold temperatures compatible with hot-dip galvanizing. The effect on the microstructure and mechanicalproperties will be presented. This TRIP-assisted steel was also galva-nized and the steel surface chemistry prior to galvanizing and reactivewetting behavior studied with respect to the oxygen partial pressureof the annealing atmosphere. The mechanism by which reactive wet-ting occurs on a selectively oxidized surface will be discussed.

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 20

Su

nd

ay P

M

www.matscitech.org 21

(MATL-001) Preclinic Test of Collagen MembranesC. M. Piña-Barba*, K. V. Dávalos-de la Cruz, Instituto de Investigaciones enMateriales, Universidad Nacional Autónoma de México, Mexico; B. León-Mancilla, Fac. de Medicina, Mexico

Biocompatibility tests of materials proposed for medical applicationsare essential for determining their ability to be accepted in the organ-ism which will be implanted. At the present time, the studies neededbetween others are in vitro (cell) and in vivo: preclinical (animal) andclinical (human) tests. In this work was developed the technique toobtain porous membranes of collagen type I from inorganic bovinebone (Nukbone®), which were used to evaluate their biocompatibilityin preclinical phase, using as animal model: rabbits. These collagenmembranes were tested in the back of New Zealand rabbits, to whichwere previously withdrew a circle of skin where were placed the mem-branes. It was found that the repair tissue process was faster and betterthan other case, furthermore the new skin present a better quality. Asa result, this membrane collagen from Nukbone® was biocompatible.

(MATL-002) Bone Tissue Growth on Microcellular Carbon FoamE. Maurer*, S. M. Mukhopadhyay, Wright State University, USA; S. Hussain,Air Force Research Laboratories, USA

Graphitic carbon foam is a relatively new material for potential appli-cations in heat sinks, radiators, and net-shape aerospace composites.This structure has interconnected porosity and high surface area suit-able for tissue growth. Graphite is also known for being bio-compati-ble. Therefore, it may be very useful as scaffolding for in-vitro tissuegrowth, but not much research has been done in this area. This studyaims at investigating such options in bone implants. Biocompatibilityof foam with osteoblasts is being researched. In addition, variouscoatings on the foam are being investigated to help with the adhesionand proliferation of the bone cells. Mechanisms of cell growth withand without surface treatments are being compared. Recent focus ison osteogenesis through studies on enzyme production of osteoblastsand osteoclasts. This will potentially lead to methods of speeding upbone-implant bonding (faster healing) and also enhancement ofbond strength and durability.

(MATL-003) Bone Cement Reinforced with Zirconium andOsteoblast CellsH. H. Rodríguez Santoyo*, M. C. Piña Barba, I. González Hernández,Universidad Nacional Autónoma de México, Mexico

In this preliminary work, a bone cement based in alpha tricalcicphosphate was reforced with zirconium oxide particles and osteoblastcells. It consists in alpha tricalcic phosphate (α-TCP), hydroxyapatite(HA), calcium carbonate (CaCO3), monohydrated calcium phos-phate (Ca(H2PO4)2.H2O), zirconium oxide particles like reinforce-ment material and osteoblast cells in order to improvement its bioac-tivity. It is a development of the Materials Research Institute (IIM) ofthe UNAM. This bone cement was immersed in a culture medium totest the proliferation cells and their life time, these preliminary resultsare important to applications in medicine.

(MATL-004) Bone cement reinforced with zirconium oxideparticlesH. H. Rodríguez Santoyo, E. B. Montufar Jiménez, Universidad NacionalAutónoma de México, Mexico, Universidad Nacional Autónoma de México,MexicoUniversidad Nacional Autónoma de México, Mexico; M. Piña Barba*,Universidad Nacional Autónoma de México, Mexico

Three different formulations from bone cements based in alpha tri-calcic phosphate were compared. The first one corresponds to onecommercial formula of bone cement, the second consists in alpha tri-calcic phosphate (α-TCP), hydroxyapatite (HA), calcium carbonate(CaCO3) and monohydrated calcium phosphate (CaH2PO4)2.H2O)The third formulation has zirconium oxide particles like reinforce-ment material of the second bone cement. The characterization of thecements consisted on physical tests of cohesion time, setting temper-ature and injectability of the paste, mechanical tests of compressive

strength and adhesion force of the cement, finally X-rays diffraction(DRX) and electronic microscopy (SEM) to test the chemical andstructural evolution of the setting reaction. The second and third for-mulations show better mechanical and chemical proprieties than thecement bone with commercial formulation. In addition, it presentsan endothermic reaction that has the vantage of no injure the adja-cent tissue.

(MATL-005) Bioinspired Ceramic Microstructures Prepared byFreezing of SuspensionsQ. Fu*, M. N. Rahaman, Missouri University of Science and Technology,USA; S. B. Bal, University of Missouri-Columbia, USA; F. Dogan, MissouriUniversity of Science and Technology, USA

A generic method based on unidirectional freezing of suspensionswas used for the preparation of porous three-dimensional bioceram-ics with microstructures mimicking those of natural materials such asbone, cork, nacre and cuttlefish bone. Microstructural manipulationin the freezing process was achieved by modifying the particle con-centration, freezing rate, and solvent composition of the suspension.The fabricated constructs had high toughness, high strain for failure,and strain rate sensitivity, typical of many natural materials. Theporous constructs could be applied as scaffolds for bone repair andregeneration.

(MATL-006) Metal Ion Doped ββ-TCP Bioceramic with EnhancedPropertiesS. J. Kalita*, A. Davenport, University of Central Florida, USA

Recent years have seen a quest for new bioresorbable biomaterials.Beta-tricalcium phosphate (β-TCP) with excellent biocompatibilityis ideal for bone-grafting. However, β-TCP suffers from poor flexuralstrength, poor densification and rapid in vivo degradation. In our re-search, we improved densification and flexural strength of β-TCP byintroducing small quantities of divalent metal ions, coupled with ma-terial-specific sintering which also controlled its degradation rate invitro. High purity metal ions, known to be prevalent in the bone min-eral, were introduced into β-TCP powder via ball milling. Densestructures were prepared by uniaxial pressing with a green density of1.7 g/cc, and then sintered at 1250°C in air. Results showed 5-12% in-crease in sintered density and 20-73% increase in microhardness.XRD analysis confirmed no alteration in phase purity. Biodegrada-tion study was performed in dynamic SBF. An in vitro assay per-formed using prostate cancer cells confirmed that these materialswere non-toxic.

(MATL-007) Synthesis and Characterization of Mg-doped ββ-TCP,and Fabrication of Mandible Graft via indirect FDMS. J. Kalita*, University of Central Florida, USA; J. P. Cardello, Timber CreekHigh School, USA

This research synthesized Mg-doped β-TCP powder, and fabricated aporous resorbable mandible bone-graft. Initially, β-TCP powder wassynthesized by a simple precipitation process. Amorphous powder wasdoped with Mg, an essential element of the bone mineral, to enhance itsproperties and stabilize the b-phase at sintering temperature (1250°C).The powder was then calcined.The resulting powder was uniaxially com-pacted, sintered, then measured for density and tested for hardness. Next,a negative mold of a section of the human mandible, prone to fracture inmost accidents, was created in an FDM machine, using a 3-D STL imageconstructed from CT data using Mimics software. Water-based slurry ofthe Mg-doped β-TCP powder was developed separately, and then infil-trated into the ABS mandible mold. The green mold was dried and thensintered at 1250°C, in a muffle furnace. The mandible graft was latercharacterized for physical properties and compared with a real mandible.

(MATL-008) Realistic Magnetic Separation of NanoparticlesS. R. Puri*, G. Mukhopadhyaya, Indian Institute Of Technology, Bombay,India, India

Separation of magnetic and nonmagnetic nanoparticles is of great in-terest because of large scale applications in biology such as separation

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 21

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania22

of RBCs from WBCs, recovery of DNA linked to Fe3O4 nanoparticleetc. In the study for the same by many researchers the nanoparticlehas been approximated to be spherical in shape. Also, the effects dueto fields induced by other magnetic particles in the medium is ig-nored. We present the, magnetic separation of nanoparticles, by ap-proximating them by more general and common shape namely an el-lipsoid and accounting for the presence of other particles. For this wefind effective permeability of the medium by Maxwell-Garnet ap-proach. The fluidic forces also change for ellipsoidal particles. Wethus develop a mathematical model (with specific results for RBCs)for describing realistically the motion of nanoparticles on the appli-cation of space varying magnetic fields. To our knowledge these re-sults are new.

(MATL-009) Fracture and Fatigue of Fe78 Si9 B13 Metallic GlassRibbonsA. B. El-Shabasy, H. A. Hassan, Ain Shams University, Egypt; W. H. Wang,Chinese Academy of Science, China; J. J. Lewandowski*, Case western ReserveUniversity, USA

Vickers microhardness indentations, tension and notch toughnesstests, as well as controlled static and cyclic strain experiments viabending over mandrels of different diameter have been performed on30 μm thick Fe78Si9B13 metallic glass ribbons. Vickers microhard-nesses of 910±100 kg/mm2 and 1030±40 kg/mm2 were obtained forthe air side and wheel side, respectively. Tensile strengths were1640±35 MPa, somewhat less than the strength predicted from mi-crohardness. The notch toughnesses obtained were 94.5±5.5MPam1/2. The static “bend over mandrel” tests revealed that the rib-bons simply deformed via shear banding for mandrel diameter assmall as 0.225 mm. Fully reversed flex bending fatigue experimentsrevealed a fatigue limit of ≥ 500 MPa via testing over mandrels withdifferent radii under cyclic strain control. SEM examination was usedto characterize all fracture surface details. These results are discussedin the light of recent work on metallic glass systems. Funds providedby NSF-EGYPT Collaborative Research Program.

(MATL-010) Effect of Thermal Treatment on the CorrosionBehavior of Fe-based Bulk Metallic GlassJ. Miller*, H. Ha, J. Payer, Case Western Reserve University, USA

An iron-based bulk metallic glass (BMG), SAM1651, has corrosionresistance equivalent to or greater than some nickel-chromium-molybdenum alloys. However due to their metastable structure, theproperties of metallic glasses can be changed by devitrification on ex-posure to high temperatures. The relationship between corrosion be-havior and structure of devitrified SAM1651 is investigated. XRDprofiles and TEM micrographs show the existence nanometer sizedcrystalline particles in the devitrified material. Cyclic potentiody-namic polarization of the devitrified SAM1651 showed a shifting ofthe anodic polarization curve to higher current densities in compari-son with the as-received material. Devitrified samples exhibited largerhystersis loops during cyclic polarization and a decrease in repassiva-tion potential.

(MATL-011) Effects of Energy Dispersion of Incident Atoms on theAomic Structure of ta-C Films : A Molecular Dynamics StudyK. Kim*, Kookmin University, School of Advanced Materials Engineering,South Korea; S. Lee, K. Lee, Korea Institute of Science and Technology, SouthKorea; P. Cha, Kookmin University, School of Advanced MaterialsEngineering, South Korea

For successful application of the Tetrahedral amorphous carbon (ta-C) films, some technical limitations should be overcome. One of themost significant problems is the high residual compressive stress ofthe ta-C film. According to the authors’ results, the calculated residualstress was twice larger than that of experiment. the conventional MDsimulation has not considered one important parameter, the disper-sion of incident atoms energies. In this MD simulation, the Gaussiandistribution of incident energies was assumed. The standard devia-tion, σ was changed from 1 to 5. The calculation result showed that

the small value of σ, i.e. the small deviation from the monochromaticenergies, dramatically reduced the residual stress while maintainingthe atomic configuration and densities. The calculated residual stressquantitatively agreed with experiments. We believe that the effect ofenergy dispersion should be considered to reproduce experimentalsituation.

(MATL-012) Atomistic modeling of the atomic size effect on glassforming abilityN. Park*, H. Nam, Kookmin University, South Korea; W. Kim, CheongjuUniversity, South Korea; Y. Kim, H. Seok, Korea Institute of Science andTechnology , South Korea; P. Cha, Kookmin University, South Korea

The famous empirical rule that large atomic size ratio increases theatomic packing density in its random packed state, which producesgood glass forming ability, is investigated through molecular dynam-ics simulations for model binary alloy systems using LJ-EAM poten-tials which can consider many-body effect. We consider several bi-nary alloys in range from 0.8 to 1.0 of atomic size ratio andconstruct their phase diagrams. It is observed that large atomic sizeratio produces good GFA but packing density decreases with in-creasing size ratio. It is also found that atomic packing densityreaches its maximum value at the point where the mole fraction ofsmall atoms is 0.5~0.6. At 0.85 of size ratio, phase diagram trans-forms from solid solution to eutectic like one. In eutectic like phasediagram, considerable diffusion of atoms is required for the precipi-tation of equilibrium crystalline phases during quenching, whichmay explain the reason why GFA improves with increasing atomicsize ratio.

(MATL-013) Corrosion Behavior of Mechanically Alloyed Cu-Zr-Ti Bulk Metallic GlassesP. Lee*, National Taiwan Ocean University, Taiwan

Recently, new Cu-based bulk metallic glasses (BMGs)have been pro-duced by conventional casting techniques at a low cooling rate. So far,many researchers have studied the glass-forming ability, thermal sta-bility and mechanical properties of these Cu-based BMGs. However,data on the corrosion behavior of Cu-based BMGs is comparativelyrare. Therefore, in this study, the corrosion behavior of mechanicallyalloyed Cu60Zr30Ti10 BMG in four different corrosive media wasstudied by the potentiodynamic method. The Cu60Zr30Ti10 BMGshows low corrosion current density and uniform corrosion in 1NH2SO4, NaOH and HNO3 solutions. The Cu60Zr30Ti10 BMG spec-imen exhibits most corrosion resistance in 1N H2SO4. The XPS re-sults revealed that the formation of Zr- and Ti-rich passive oxide lay-ers provide a high corrosion resistance in 1N H2SO4 and HNO3solutions, while the breakdown of the protective film by Cl- attackwas responsible for pitting corrosion in 3 wt % NaCl solution.

(MATL-014) Preparation and microstructural evolution of foamedglasses by sol-gel processR. Suarez-Orduña*, L. P. Rivas-Vázquez, J. Hernandez-Torres, M. Valera-Zaragoza, Universidad del Papaloapan, Mexico

The feasibility to prepare foamed glass specimens by using a sol –gel process, followed by a conventional heating of the compact,was investigated. The glass in the system SiO2 – Na2O – CaO werepreliminarily prepared by sol-gel method. The process utilizes therapid viscosity change during gelation to stabilize the structure ofa foamed SiO2 – Na2O – CaO sol. After the gel formation stage,firing of the compacted disk glass was conducted over a tempera-ture range of 650–850 °C for 1 h. Microstructural observationsconducted by SEM showed the formation of a new glass phasewhich incorporates water. Manipulation of gel viscosity resultedin a minimum cell size of 90 μm. The lowest apparent densityachieved on these glass compacts heated at 700 °C for 1 h was 0.36g/cm3. This value is similar to that of other foamed glasses thathave close cell network and low thermal conductivity (0.0021W/cm/°C).

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 22

Su

nd

ay P

M

www.matscitech.org 23

(MATL-015) TSDC Spectroscopy of Polyester Amide PolymerLiquid CrystalS. Garg, G. Goyal, B. K. Kaushik, S. K. Mahna*, National Institute ofTechnology, India

In the present paper we report the thermally stimulated depolariza-tion current investigations in polyester amide plc. The tsdc character-istics were obtained for polarizing field (Ep) 5-25kV/cm and polariz-ing temperature (Tp) ranging from 800-1900C. The tsdccharacteristics in the temperature region 200-2500C consist of currentmaxima termed as γ (around 300C), β (around 1000C) and α (around1500C) in the ascending order of temperature. The β and α-peakshave been assigned to the dipolar and space charge relaxationsprocesses of PLC. The multiphasic system associated to the PLC is re-vealed from the nature of variation of these maxima with Tp and Ep.The liquid crystalline phase gives its own current maxima in the hightemperature region termed as δ-relaxation (around 2100C). The acti-vation energy and the other relaxation have been estimated usingBucci-plot method.

(MATL-016) The Computational Modeling of the cascade areas inconstructional materialsA. Togambayeva*, A. Kupchishin, Al-Farabi Kazakh National University,Kazakhstan; F. Komarov, Belarus State University, Belarus; T. Shmygaleva, Al-Farabi Kazakh National University, Kazakhstan

The technique that allows receiving of analytical expressions and cal-culating of the cascade areas on all depth of an irradiated materialwith the aim of hardening a material and generation of metals con-nections, basically, in a superficial layer is offered in the given work.Selection of approximating expressions and calculations of cascade-probabilistic functions (CPF) in view of losses of energy at an irradi-ation of iron by ions of carbon and iron are made. Areas of CPF’s re-sult presence are found and laws of their behavior are received. Theinfluence of interactions number and depths of penetration on rangeof CPF’s definition is considered. Calculations of cascade areas are ex-ecuted and laws of behavior of area of result are revealed. The featuresarising at calculations are revealed and the analysis of results is made.

(MATL-018) Mixed Mode Fracture Behavior of A Plasma-SprayedZrO2-Y2O3 Thermal Barrier Material SystemD. Zhu*, NASA Glenn Research Center, USA; S. R. Choi, Naval Air SystemsCommand, USA; L. L. Ghosn, NASA Glenn Research Center, USA

The combined mode I-mode II fracture behavior of anisotropicZrO2-8wt%Y2O3 thermal barrier coatings was determined in asym-metric flexure loading at both ambient and elevated temperatures. Afracture envelope of KI versus KII was determined for the coatingmaterial at ambient and elevated temperatures. Propagation angles offracture as a function of KI/KII were also determined. The mixed-mode fracture behavior of the microsplat coating material was mod-eled using Finite Element approach to account for anisotropy andmicro cracked structures, and predicted in terms of fracture envelopeand propagation angle using mixed-mode fracture theories.

(MATL-019) Adhesion of vitreous enamel coatings on the carbonsteel applied via various methodsD. Kim*, M. Kim, KEPCO , South Korea

Carbon steel heating elements of the gas-gas heat exchanger for fluegas desulfurization systems were being coated with vitreous enamel.The adhesion properties of the enamel coating applied via dry elec-trostatic spray process and wet (spray and dipping) process werestudied. The adhesion strength according to the European code DEZ-MB 7.10.3 was much higher with the dry process than with the wetprocess. The microstructure of the coating analyzed using an opticalmicroscopy and a scanning electron microscopy showed that thebubbles in the coating were more uniformly distributed in the dryprocess than in the wet process. The microstructure of enamel/steelinterfaces revealed that the dendrites grew uniformly from the steelfor the dry process, while those for the wet process grew unevenly and

separated from the steel. This suggests that the uniformly distributeddendrites acted as anchors for better adhesion for the dry process.

(MATL-020) Mixing of Solid Particles in Coarse ParticleFluidized BedsH. Fan*, D. Xu, Y. Chen, H. Li, J. Fan, Xi’an University of Architecture andTechnology, China

This paper presents a study of the mixing behaviors of solid particlesin a gas-fluidized bed by means of a discrete particle simulation. Theoverall mixing extent of particles in axial and radial is represented bythe mixing index. Accordingly, the time needed to reach the maxi-mum mixing value is indicated by the minimum mixing time. In thissimulation, the tracer particles are monitored momentarily to acquiretheir locations and the mixing index. This paper focuses on five fac-tors affecting the mixing extent, the gas velocities, the bed height, thegas temperature, the particle density and the particle size. It is showedthat there is a maximum value of mixing index and a relevant mini-mum mixing time for a given operation condition. These five factorshave different effects on particles mixing.

(MATL-021) Faradayic EPD Processing of Thermal BarrierCoatingsJ. W. Kell*, H. McCrabb, Faraday Technology, USA; B. Kumar, University ofDayton Research Institute, USA

An electrically mediated electrophoretic deposition process (FaradayicEPD) for thermal barrier coatings is being developed by Faraday. Uni-form coatings of yttria-stabilized zirconia (YSZ) have been deposited, in anon-line of sight fashion, for use in thermal barrier systems in natural gasand synthesis gas environments. MCrAlY bond coated Ni-based superal-loy substrates have been deposited on and have been subjected to a binderburnout and sintering process. The samples were then subjected to a bat-tery of tests, such as surface roughness measurements, microstructuralexamination, thermal conductivity measurements, thermal cycling tests,and other appropriate tests of merit, to determine their feasibility for usein gas turbine engines. Studies have shown that the process can uniformlydeposit YSZ with good surfaces, decreased edge effects, and with proper-ties consistent with similar systems processed through other methods.

(MATL-022) Corrosion Resistance of ZrO2, Al2O3, CeramicCoatings in NaOH SolutionM. I. Espitia*, Universidad Michoacana de San Nicolas de Hidalgo, Mexico;M. Contreras-García, Universidad Michoacana de San Nicolás de Hidalgo,Mexico; M. Espinoza-Medina, 3Instituto Mexicano del Petróleo, Mexico; H.Orozco-Hernández, Universidad Michoacana de San Nicolás de Hidalgo,Mexico

Al2O3 and ZrO2 ceramic coatings deposited on metals surface changegreatly the corrosion behavior.It is well known that engineering qual-ity Al2O3 and ZrO2 ceramic exhibit excellent properties of chemicalstability and corrosion resistance. In this work, Al2O3 and ZrO2 coat-ings were obtained by cathodic deposition and were characterized bySEM and AFM. ZrO2 and Al2O3 coatings SEM morphologies wereuniform dense and continuous. The AFM the observed morphologiesshowed nanostructured coatings. The corrosion behavior into aNaOH 0.05M solution at room temperature was determined by po-tentiodynamic polarization technique. The ZrO2 and Al2O3 coatingselectrochemical evaluations showed a protective behavior and highcorrosion resistance into (1M) NaOH solution at room temperature.Both Al2O3 and ZrO2 showed better corrosion resistance than themixed oxides coating. Acknowledgements: The authors acknowledgethe financial support from, CIC UMSNH, and to Victor Ivan Macias.

(MATL-023) Preparation and Characterization of Bioglass BasedCoatings on 316L Alloy Treated under Hydrothermal ConditionsR. Suarez-Orduña*, L. P. Rivas-Vazquez, Universidad del Papaloapan,Mexico; J. C. Rendon-Angeles, CINVESTAV, Mexico; K. Yanagisawa, KochiUniversity, Japan

An alternative method for preparing bioglass based ceramic coatingson stainless steel 316L substrate was investigated by a reaction under

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 23

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania24

a hydrothermal hot pressing method. The bioglass coatings on themetallic substrate were obtained at 200 °C for 120 min, with a confin-ing pressure of 20 MPa. It was observed that the bonding of the bio-glass phase with the substrate proceeded at low temperature (175 °C),and simultaneously the densification process of the particles oc-curred. The densification of bioglass under HHP treatments pro-ceeded by a mechanism of dissolution–precipitation of bioglass pow-der. Microstructural observations conducted at the interface betweenthe metallic substrate and the solidified glass, revealed the formationof a very thin layer which was formed by the dissolution of the oxideground coat layer. It was found that the maximum cohesive strengthbetween the ceramic coating and the substrate was 13 MPa.

(MATL-024) Effect of sol viscosity on the structure of NiO-SiO2nanocomposite thin films by the sol-gel methodJ. Hernandez-Torres, R. Suarez-Orduña*, Universidad del Papaloapan,Mexico; L. García-Gonzáles, Centro de Investigación en Micro yNanotecnología, Universidad Veracruzana, Mexico; A. Mendoza-Galvan,Centro de Investigación y de Estudios Avanzados del IPN - UnidadQuerétaro, Mexico

SiO2 thin films containing nickel were deposited on corning 2947glass, fused-quartz slides and silicon wafer substrates using the sol-gel method. The Si to Ni nominal atomic ratio in the coatings was1.2. The films were obtained to different values of sol viscosity, whichwas achieved by aging the solutions with various amounts of ethanol.The effect of sol viscosity on the structure of the films was performedusing infrared transmission spectroscopy, X-ray diffraction, opticaltransmission and reflection spectroscopy in the UV-visible region,and auger spectroscopy. The results indicate that the formation ofNiO as a surface thin layer is obtained for films prepared from solu-tions with a lower viscosity. On the other hand, films prepared fromsolutions with higher viscosity, the NiO was formed in the bulk ofthe film.

(MATL-025) Method for Surface Modification of Aluminum PartsS. Barseghyan*, M. Atzmon, National Academy of Sciences, Armenia

The aim of the presented research is to demonstrate new approachfor surface modification and hardening of aluminum parts. The ap-proach is based on the process of mechanical alloying proceeding be-tween Al substrate and Mo powder. By this method surface modifica-tion of several aluminum substrates have been carried out. XRD,SEM and microhardness indentation were used to evaluate the pa-rameters of the formed layers. It has been shown that mechanical al-loying brings to the formation of Mo coating on the surface of Al sub-strate. The thickness of coating is about 8-10 micron at dry alloyingand 3-5 micron at wet alloying. The presence of a Mo layer increasesthe sample microhardness by a factor greater than three. Post deposi-tion annealing at about 550°C could be applied for further modifica-tion of the formed layer. Due to the improved hardness and corrosionand wear resistance, the coatings are of interest for numerous practi-cal applications.

(MATL-026) Simulation of Low Pressure Cold Spray as a PowderShock Consolidation ProcessW. G. Arthur*, E. Leshchinsky, R. Maev, University of Windsor , Canada

Numerical simulations of shock wave propagation through the pow-der mixtures were performed to investigate the characteristics of de-formation during Low Pressure Cold Spray (LPCS) of powder mix-tures. The analysis of the spraying process is based on amicromechanics approach using multiple particle configurations.The material considered is elasto-viscoplastic with interparticle fric-tion. Two-dimensional stress-strain analysis of discrete particles invarious packed arrangement was carried on the base of plane straindeformation model. The finite element method using an explicit dy-namic analysis procedure was used for the simulations. The finalshape and temperature variations within the particles were analyzed.The results are believed to provide a better understanding of theLPCS shock consolidation features.

(MATL-027) Composition and properties of mould flux glassesP. Stoch*, Institute of Atomic Energy, Poland; M. Ciecinska, AGH-Universityof Science and Technology, Poland; L. Stoch, Institute of Glass Ceramics,Refractories and Building Materials, Poland

The influence of chemical composition on the crystallization abil-ity and thermal properties of mould flux glasses from the SiO2-CaO-Al2O3-Na2O- CaF2 system was studied. FTIR spectra revealedthat with CaF2 content increase, glass structure polymerization de-gree changes. Polymerization degree increase is accompanied by anincrease of glass softening temperature but more rapid melt vis-cosity decrease. The changes of glass crystallization ability andcrystal phase formation with temperature increase as dependenton CaF2 content ware studied. At CaF2 10-13 wt.% content cuspi-dyne and pseudowollastonite are formed when the CaF2 contentincreases, fluorite accompanied by cuspidyne appear and at ahigher temperature complex silicates: gehlenite and albite are crys-tallizing. Influence of glass crystallization on its properties asmould flux were studied. Substitution of CaF2 by B2O3 decreasessoftening temperature of glass but melt viscosity is diminishingwith temperature slowly. Pseudowolastonite is the glass crystalliza-tion product.

(MATL-028) Magnesium Phosphate Crystal Precipitation onMagnesium Borosilicate Glass when Reacted in a PhosphateSolutionS. Kim*, J. Nam, C. Kim, Inha university, South Korea

When the magnesium borosilicate glass with special composition isreacted in the solution containing phosphate ions, Mg2+ ions leachedout of the glass surface can combine with phosphate ion in the solu-tion and form phosphate crystals on the glass surface. The phosphateions can be removed from the solution in this manner. In this study,various composition of glass in the system of SiO2-B2O3-Na2O-MgOare prepared and then reacted in a solution containing phosphateions with different concentration for various times. After reaction theconcentration of phosphate was measured with U.V.-visible spec-trometer. The reacted glass surface was also observed by SEM andXRD. The increase in Na2O and B2O3 in the glass composition en-hanced the leaching of Mg2+ ions from the glass surface. This pro-moted the formation of magnesium phosphate crystal formation andthe removal of phosphate ions from the solution.

(MATL-029) Sodium tracer diffusion in sodiumborosilicate glassesX. Wu*, R. Dieckmann, Cornell University, USA

To contribute to a better understanding of the mixed glass former ef-fect, a study of the diffusion of sodium in sodiumborosilicate glasseshas been initiated. This study involves sodium tracer diffusion exper-iments in glasses with varying boron oxide and silica contents. Theradioactive isotope used in the diffusion studies is sodium-22. Firstexperimental results will be presented and discussed.

(MATL-030) Laser Machining of CeramicsA. N. Samant*, N. B. Dahotre, University of Tennessee, USA

Machining of ceramics by lasers was investigated in this study byvarying the laser parameters in different combinations. Several num-ber of pulses were chosen to machine blind cavities of various depthsand also a cavity through the entire thickness of different ceramics. Amathematical model was developed which took into account the ther-mal effects for melting the material, vapor pressure effect for expellingout the molten material and the effect of surface tension in reducingthe expelled depth .The model also accounted for the transient effectof de-focusing of laser beam because of the variation in machineddepth as function of material expelled during machining, thus esti-mating the melt depth during each pulse more precisely. The devel-oped model would be useful in advance prediction of the total ther-mal energy and time necessary for machining desired material depth.

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 24

Su

nd

ay P

M

www.matscitech.org 25

(MATL-031) Anodic titanium oxide films with improved porousstructureI. Kolesnik*, D. Petukhov, D. Buldakov, A. Eliseev, A. Lukashin, Y. Tretyakov,Moscow State University, Russian Federation; S. Grigoriev, PetersburgNuclear Physics Institute, Russian Federation; H. Eckerlebe, GKSSForschungszentrum, Germany

Porous anodic oxide films consist of uniform parallel cylindricalchannels or nanotubes. Their diameter and film thickness can be var-ied in a wide range and depend on synthesis conditions. Such filmscan be considered as promising prototypes ceramic oxide mem-branes. For this purpose one should obtain films with dense packingof nanotubes which have enough thickness and mechanical strength.The aim of our work was preparation of anodic TiO2 with improvedporous structure. The samples were obtained by anodic oxidation ofmetallic titanium. To improve structural parameters of the films weused high-purity titanium and two-stage anodization process. Thisapproach allowed us to obtain highly ordered films with open pores,ordered hexagonal domain structure and thickness up to 300 μm.After calcination at temperatures up to 600°C amorphous titaniumoxide can be transferred to anatase without destruction of porousstructure. This work was supported by RFBR (grants 06-03-89506,06-08-01443) and FASI (grant 02.523.12.3015)

(MATL-032) Preparation and Characterization of Iron-dopedMesoporous TitaniaI. Kolesnik*, M. Kharlamova, A. Eliseev, A. Lukashin, Y. D. Tretyakov, MoscowState University, Russian Federation

Photocatalytic activity of TiO2 is determined by many factors: specificsurface area, porosity, crystallinity, phase composition and light ab-sorption spectrum. In this work we performed synthesis of meso-porous TiO2 with high specific surface area (up to 320 m2/g),nanocrystalline pore walls, consisting of anatase and brookite, andhigh photocatalytic activity. Optical properties of mesoporous TiO2were tuned by doping with Fe3+. It was found that addition of Fe3+

leads to modification of morphological and electron properties andchange of photocatalytic activity of titanium oxide. Iron-doped tita-nia samples possess larger pore radius and consist of bigger nanocrys-talline particles than undoped TiO2. Also doping leads to decrease ofoptical electron excitation energy from 3,35 eV to 3,24. MesoporousTiO2 comprising 0,04 mol.% Fe possesses high surface area (210m2/g) and the highest photocatalytic activity. This work was sup-ported by RFBR (grants 06-03-89507, 06-08-01443) and FASI (grant02.523.12.3015)

(MATL-033) Highly purity AlN powders synthesized by SHS methodJ. Pee*, Y. Kim, H. Kim, E. Choi, KICET, South Korea

Aluminium nitride (AlN) powders were prepared by self-propagatinghigh-temperature synthesis (SHS). Aluminium and AlN powder mix-tures with weight ratios of about 4:6, in the presence of 0.1-3wt.%carbon powders as additives were ignited in a nitrogen atmosphere of3-5kgf/cm2. Highly crystalline AlN particles with regular hexagonalmorphology were obtained in the presence of carbon. The mi-crostructure development during the reaction and the influence ofthese additives were determined by SEM and XRD analysis of the re-sulting products. We also successfully synthesized high purity AlNpowders with low residual oxygen contents(0.75wt.%).

(MATL-035) Innovative Si3N4 ready-to-press powders foradvanced ceramic applicationsT. Schmidt, H.C. Starck GmbH, Germany; K. Beck*, H.C. Starck Inc., USA; S.DiPietro, Exothermics Inc., USA

Due to its unique properties, in particular its high thermal shock re-sistance and high fracture tough¬ness, Si3N4 has found its place inmany technical applications and hence, became an essential materialin the Engineered Ceramics world. Nowadays, Si3N4 is also discussedto be used for armour related applications, which may lead to futurehigh volume demand and will require reliable and read-to-use mate-

rials. For many years, H.C. Starck is producing a variety of α-SiliconNitride powders. Based on these commercially available Si3N4 pow-ders, H.C. Starck has recently developed spray dried Si3N4 premixtype powders. These Si3N4 premix powders are ready to use (or readyto press, rtp), as they are fully formulated, containing additives, tem-porary binders, and pressing aids. These ready-to-press powders areespecially designed for uniaxial dry pressing to produce sinteredSi3N4 parts. Certain premix formulations can also be adapted forCold Isostatic Pressing (cip) and green machining.

(MATL-036) Preparation and Characterization of Fused SilicaBased Ceramic Cores Used in Superalloy CastingM. Arin*, A. B. Kayihan, S. Sevik, The Scientific and Technological ResearchCouncil of Turkey, Turkey

Fused silica based ceramic core samples with the addition of Al2O3or ZrO2 (calcined, 3 mol% Y2O3 stabilized) powders have been pre-pared by injection molding and sintered at 1200-1550C for 1 h. Theeffects of crystalline phase content, sintering conditions, and grainsize on flexural strength, shrinkage, and liquid metal interactions ofthe ceramic samples have been investigated. The experimental workrevealed that optimal composition can be achieved by the addition of17 wt% stabilized ZrO2 to fused silica and sintering at 1550C for 1 h,as flexural strength increasing to ~15 MPa and the shrinkage is ~1%.α-quartz to α-cristobalite transformation increases with sinteringtemperature. Since fused silica is known as resistant to thermal shock,the iniquitous reaction of the ceramics with Ni based superalloy is as-cribed as the result of microcracking due to differential densificationduring sintering, loss of adherence between the grains, and phasetransformation of ZrO2 on cooling.

(MATL-037) Advanced Processing Routes for Ultra HighTemperature CeramicsM. Gusman*, ELORET Corp. at NASA Ames Research Ctr., USA; K. Lau, A.Sanjurjo, SRI International, USA; S. M. Johnson, M. Gasch, NASA AmesResearch Center, USA

Sharp leading edges of hypersonic space vehicles require thermal pro-tection materials able to withstand reentry conditions. While UltraHigh Temperature Ceramics (UHTCs) exhibit some promising prop-erties, such as thermal conductivity, fracture toughness, and oxida-tion resistance, improvements are still being pursued. This researchfocuses on approaches to developing UHTCs by incorporating a pro-cessing method to enhance properties and reduce processing temper-atures. Hafnium diboride powders, used to produce UHTCs, arecoated using a fluidized bed reactor chemical vapor deposition (FBR-CVD) technique. The coated boride powders are then hot-pressedand characterized. FBR-CVD is used to manipulate coatings onboride powders and to control grain boundary composition and sec-ond- and third-phase variations within the UHTCs.

(MATL-038) MgAl2O4/SiC Composite Ceramic Material Producedby Combustion SynthesisP. Kirill*, E. Diatlova, L. Nikitina, BELARUSIAN STATE TECHNOLOGICALUNIVERSITY, Belarus

An effective method to obtain the composite materials is the combus-tion synthesis (CS). Applying the CS gives a wide potential for theproduction of composite materials containing various crystal phasessuch as spinel and silicon carbide. This work comprises the investiga-tion of the composition of phases MgAl2O4/SiC prepared by the CS.The reactionary interacting was initiated by a hot coil which had beenput into the initial components mixture. In the course of the experi-mental researches there has been obtained the material containingabout 70-80 % MgAl2O4 and up to 20 % SiC and having the com-pressive strength of up to 100 MPa, the density of 1100-1400 kg/m3,the electric conduction of 104-106 Ohm*cm. The materials have thestructure consisting of lamella-shaped spinel crystalline formationsand silicon carbide in the form of fibers. There has been defined theinfluence of the initial components on the phase formation processand the properties of the generated MgAl2O4/SiC materials.

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 25

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania26

(MATL-039) Pure and Mg/Zn/Si-doped Nanocrystalline TiO2through Sol-Gel processingA. K. Menon, S. J. Kalita*, University of Central Florida, USA

Nanocrystalline TiO2 gained significant attention due to its optical,biological, dielectric and catalytic properties. Earlier, we developed asol-gel technique to synthesize 5-12 nm anatase powder. The objec-tives here were to investigate influences of nano-powder, dopants andsintering; and develop a correlation between microstructure, compo-sition and mechanical properties. Synthesized powder was dopedwith MgO, ZnO and SiO2 in small quantities (1, 2 & 3 wt.%); com-pacted uniaxially and sintered at 1500°C. Dopants enhanced the geo-metric sintered density by 2.1%, hardness by 12% and biaxial flexuralstrength by 10%. MgO addition (2 wt.%) showed the highest densityof 3.87 g/cc (91.2% of the theoretical density of rutile); whereas ZnOaddition (2 wt.%) showed the maximum hardness of 502 HV. ForSiO2 addition 3 wt.% showed better properties. XRD confirmed rutilephase after sintering, while SEM showed grain refinement. Ramanspectroscopy studies were also performed.

(MATL-040) Mechanical Behavior of Spark Plasma SinteredAlumina-Zirconia Nano-composites with Addition ofHydroxyapatiteS. Li*, H. Izui, M. Okano, Nihon University, Japan; W. Zhang, Xi’an universityof technology, China; T. Watanabe, Nihon University, Japan

Composition of 3 mol% yttria-stabilized zirconia (3-YSZ) reinforcedwith 20 wt% alumina (TZP-3Y20A) nano-composites were preparedusing spark plasma sintering (SPS) process at temperatures in the1000 to 1400°C range. Different volume fraction of hydroxyapatite(HA) (10 vol%∼50 vol%) was added as bioactive materials to im-prove the biocompatibility of the Al2O3-ZrO2 composites. The ef-fects of HA on the sintering densification, microstructure and me-chanical properties of the Al2O3-ZrO2 composites were analyzed.Flexure strength and young’s modulus of composites decreased grad-ually with increasing volume fraction of HA. The HA added Al2O3-ZrO2 nano-composites had higher fracture toughness and microhardness than those of HA monoliths, while flexure strength andyoung’s modulus kept the same level compared to that of pure HA ce-ramics when the volume fraction of HA increased up to 50 vol%.

(MATL-041) Fabrication of high strength porous mullite ceramicsby microwave sinteringS. Bodhak*, S. Bose, A. Bandyopadhyay, Washington State University, USA

The objective of this research is to develop a processing technique tofabricate high strength porous mullite ceramics via microwave sinter-ing route. Mullite samples were sintered using a 3 KW, 2.45 GHz mi-crowave furnace. Sintering temperatures were in the range of 1200-1500oC, keeping the sintering time constant at 60 minute. With anincrease in sintering temperature from 1200oC to 1500oC, the poros-ity decreases from 35 to 18.5% and the compressive strength increasesfrom 76 MPa to 201 MPa. Furthermore, with addition of 1 wt% MgOas sintering aid, strength up to 277 MPa was achieved at 15.3% poros-ity. SEM investigation revealed that neck growth between particles bysurface diffusion can significantly enhance strength with minimal in-crease in density. Microwave sintering data, when compared withthose of conventional sintering, reveal that localized heating of mi-crowaves promotes greater shrinkage than conventional sintering.

(MATL-042) Powder Injection Molding of SiC Sintered inMicrowave OvenW. Idalgo*, UFSCar, Brazil; J. Aroni, G. Link, Forschungszentrum Karlsruhe,Germany

The Micro Ceramic Injection Molding (Micro-CIM) allows higherdegree of automation, higher productivity, complexity of forms andlow dimensional tolerance deviations. The objective of this work is tomeet the Micro-CIM advantages with typical properties from the sil-icon carbide (SiC) like wear resistance, refractoriness under aggres-sive media and electrical resistance. Injection molding masses for

Micro-CIM (feedstocks) are performed in a Z-kneder, measured bycapillary rheometer and injected in form of disks. Part of the samplessintered between 1,800°C and 2,100°C in a microwave furnace underN2 atmosphere are compared with samples sintered using HIP-Process. Samples show up to 96% densification and, in some samples,closed porosity was observed. Typical electrical resistance values arefound in the range of kΩ. It was possible to obtain enough higherdensification and good electrical values of CIM-SiC parts for use insome applications like micro-reactors or pumps for aggressive mediaat higher temperatures.

(NANO-001) Finite Element Analysis on Thermal NanoimprintLithography ProcessB. Cho*, S. Park, T. Won, INHA University, South Korea

Nanoimprint lithography (NIL) relies on a direct mechanical defor-mation of the resist material and can therefore achieve resolutionsbeyond the limitations which are set by a light diffraction or a beamscattering. In addition, NIL is expected to realize a low cost and high-throughput production. In this work, we modeled the NIL processand employed commercially available software, COMSOL Multi-physics, for the implementation of our model. We report the stressdistribution of the polymer deformation process on the imprintingpressure. A numerical simulation model imprinting a SiO2 stampinto a Polymethyl methacrylene (PMMA) film is suggested in orderto analyze the pattern transfer and its related phenomena in thermalNIL. These calculated results represent asymmetric von Mises stressdistribution of the polymer around the external line caused by thesqueezing flow under flat space.

(NANO-002) Effects of Notch Radius, Test Temperature and MixedMode Loading on the Toughness of a Nano-Structured AlCompositeH. A. Hassan, A. B. El-Shabasy, Ain Shams University, Faculty of Eng., Egypt;J. J. Lewandowski*, Case Western Reserve University, USA

A nanostructured Al89Gd7Ni3Fe1 composite alloy was made fromextruding its atomized amorphous powder at different extrusion ra-tios (ER). The extruded alloy contained fcc α-Al, intermetallic parti-cles, and a small amount of τ1 particles. The effects of changing thenotch radius from fatigue precrack to 100 μm on mode I fracturetoughness were studied at different test temperatures (e.g. 298K and498K). The effects of mixed mode (I/II) loading using different offsetratios were also studied at these temperatures. Increasing the testtemperature showed a significant effect on the fracture toughness forboth mode I and mixed mode I/II conditions. Fracture surfaces wereexamined to reveal the nature of failure of such nanostructured Alcomposite materials at these loading conditions. Funding providedby Fulbright grant (HAH) with materials supply and partial supportfunding via Pratt and Whitney.

(NANO-003) Controlling the Processing Parameters forConsolidation of Nanocrystalline Micro and Nanopowders intoBulk Nanostructured MaterialH. G. Salem*, A. A. Sadek, American University in Cairo, Egypt

Mechanical milling was employed for the refinement of a nanocrys-talline 40μm particle size powder of Al-2124 alloy into nanopowders<100nm. Consolidation maps were constructed for hot uni-axialpressing for preliminary densification, followed by equal channel an-gular pressing (ECAP) at the minimum possible deformation tem-perature for final densification. Micronpowder hot compacts (HC)exhibited highest densities and hardness at pressure and temperatureranges of 375-450MPa and 420-480°C for 60 min, respectively.Nanopowders HC displayed the highest densities and hardness overpressure and temperature ranges of 525-600MPa and 420-480°C for60min, respectively. The hardness and compressive strength of thenanopowder HC were 219% higher than that produced for the mi-cronpowder. ECAP one-pass enhanced the density, hardness andcompressive strength of both HC with slight grain growth comparedto the initial powder.

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 26

Su

nd

ay P

M

www.matscitech.org 27

(NANO-004) Mechanically Activated Nanoparticle Deposition forRich Triple-Phase-Boundary SOFCH. Abe*, K. Sato, G. Okamoto, M. Naito, Osaka University, Japan

In our modified co-precipitation method, NiO/YSZ compositenanopowder with crystalline size of less than 10nm was fabricated.The thick nanoporous films were successfully deposited on dense YSZelectrolyte through mechanical activation of NiO/YSZ compositepowder. The deposition rate was exceeding 1um/min. The porosity ofthe film was larger than 60%. The obtained nanoporous films hadenough adhesion onto substrate and enough film strength. Anycracks were not induced in the subsequent annealing up to 1200 de-grees C. The resultant Ni/YSZ SOFC anode showed a significant im-provement of electrochemical reactivity. Detailed analysis revealedthat the observed high performance was due to enlarged triple phaseboundary (TPB) in the anode.

(NANO-005) The Syntheses and Physical Properties of NanosizedSiO2-Coated Fe2O3J. Pee*, Y. Kim, H. Kim, E. Choi, KICET, South Korea

We successfully synthesized silica coated Fe2O3 nanoparticles usingmicroemulsion method. First, γ-Fe2O3, α-Fe2O3 particles were pre-pared by hydrothermal and thermal decomposition method. Pre-pared nano-particles were characterized by SEM and TEM. Hy-drophobic γ-Fe2O3 nanoparticles were coated with silica usingreverse micro-emulsion technique. Hematite, α-Fe2O3 as a pigment,was coated with silica using tetraethylorthosilicate (TEOS) andcetyltrimethyl ammonium bromide (CTAB) in basic solution. Silicathickness of both materials can be controlled through the varioussynthetic conditions (20 to 100nm) and physical properties of silicacoated particles were characterized by TEM, TGA and UV.

(NANO-006) Carbon Nanotubes Obtained by ECC Technique withCobalt Chloride as Catalyst PrecursorM. Wang*, Research Center for Sensor Technology, Beijing InformationTechnology, China

In this paper we report the preparation of carbon nanofibers (CNTs)by ethanol catalytic combustion (ECC) technique. We employedcobalt chloride as catalyst precursors, copper plate as substrate andethanol as carbon source. We have obtained the carbon nanotubeswhich are very straight and uniform. In order to have a better under-standing of the growth mechanisms, and study the influence of cata-lysts on CNTs growth respectively, we employed SEM and TEM to ex-amine the morphology and microstructure of the obtained CNTs.

(NANO-007) Transformation of Mechanically Milled andCompacted Crystalline Ni and Ti to Bulk Amorphous AlloyN. Monsegue*, A. O. Aning, Virginia Tech, USA

Equiatomic composition of Ni and Ti powders were mechanicallymilled and compacted using a combustion driven compaction devicethat utilizes controlled release of energy from combustion of naturalgas. Milling was done cryogenically in an attritor to produce an aver-age lamellar size of about 50 nm in the powder particles. Compactedsamples were annealed isothermally between 250°C and 400°C for upto 50 hours in a vacuum to produce the amorphous phase. XRD,DSC, TEM, EBSD and nano-indentation were used to characterizemilled powders and the compacts. The compacts were compositesmade up of nanocrystal (Ni3Ti) and Ni-Ti amorphous phases, andtheir relative amounts depended on the annealing temperature andtime. Hardness increased from 6 Berkovich Hardness (BH) for the asmilled powders to about 8.5 BH for the composite compacts.

(NANO-008) Synthesis, Phase Stability and Thermal Evolution ofBi2O3 Nanoparticles Containing Cr/Cu AdditionsO. Dominguez*, Instituto de Metalurgia, Mexico; I. Esparza, CIMAV, Mexico;M. Paredes, L. Flores, A. Aviles, Instituto de Metalurgia, Mexico; R. Martinez,CIMAV, Mexico

Technological uses of Bi2O3 are in the field of advanced ceramics.The d-Bi2O3 phase has received attention due to its ionic conductiv-

ity. In pure form its useful temperature range is from 730° to 825° C.The d-phase can be stabilized to lower temperatures by the additionof oxides like WO3. In the present work, Bi2O3 nanoparticles wereobtained using aqueous solutions of Bi(NO)3 dissolved with HNO3.Depending on the alkali, dispersant, temperature, etc., the final prod-uct could be amorphous Bi(OH)3, or well crystallized a-Bi2O3. Mod-ified Cr/Cu Bi2O3 nanoparticles were obtained adding smallamounts of their corresponding salts to the aqueous solutions ofBi(NO)3 and following the same procedure. The Bi2O3 nanoparticlesand the thermal evolution of the synthesized nanocomposites werecharacterized using XRD, DTA/TGA, IR, SEM and TEM.

(NANO-009) Fabrication of CNT dispersed Si3N4 ceramics withelectrical conductivity and high strengthS. Yoshio*, J. Tatami, T. Wakihara, K. Komeya, T. Meguro, Yokohama NationalUniversity, Japan

Si3N4 ceramics have excellent mechanical properties to be used for ce-ramic bearing. We have been researched CNT dispersed in Si3N4 ce-ramics with electrical conductivity. However, their strength is not suf-ficient for bearing application because CNTs disturbed densificationat high temperature. In this study, we fabricated CNT dispersed Si3N4ceramics by using various amounts of CNTs fired at different temper-atures. Relative density of the sample fired at 1800OC increase with anincrease in the CNT loading because larger amount of CNTs seems toimprove creep resistance of Si3N4 ceramics. Strength of the CNT dis-persed Si3N4 ceramics fired at 1800OC was lower than that of mono-lithic Si3N4 ceramics. On the other hand, the firng at 1700 and1750OC suppressed the disappearance of CNTs and improved relativedensity. The CNT dispersed Si3N4 ceramics fired at 1700 and 1750OCshowed high electrical conductivity and strength as high as the Si3N4ceramics without CNTs.

(NANO-010) Large-Scale Synthesis (Mn0.5Zn0.5)Fe2O4-BaTiO3Alloy with Controllable NanostructureY. Yang*, S. Priya, J. Li, D. Viehland, Virginia Tech, USA

Multifunctional nanomaterials have lots of potential application innovel devices. (Mn0.5Zn0.5)Fe2O4-BaTiO3 nanoparticle is one ofthese kind materials has ferroelectric and magnetic properites. Usesolid-state chemical reaction we can gain this nanopparticle in large-scale with controllable shape. These novel nanostructured materialswill demonstrate wide applications.

(NANO-011) Novel method to control microstructure andproperties of inkjet printed metal films: laser annealingY. Yoon*, S. Yi, J. Jung, J. Yim, Y. Joo, Seoul National University, South Korea

Inkjet printing is a pattern-on-demand technology for metalliza-tion.However, additional thermal treatment is required due to natureof ink; suspension and dispersant should be eliminated to have con-ductor reasonable resistivity by thermal treatment. Common thermaltreatments are conducted by a furnace. However, its uniform heatingsource limits temperature of thermal treatments due to degradationof materials neighboring metal line. So, laser annealing is an alterna-tive approach to minimize it by control incident energy density, defo-cusing, and pulse duration time. Optimizing these conditions, mi-crostructure and resistivity can be controlled. In this study,microstructure evolution, such as grain size and pore density, ofinkjet printed Ag film was observed by FE-SEM. Resistivity alsomeasured by a 4-point probe. Strong dependence on temperature wasfounded, and effects of thermal treatment were studied by modelstudy on grain growth and resistivity decrease.

(NANO-013) Cluster Nature of the Solvent Features of Single-WallCarbon NanohornsF. Torrens*, Universitat de Valencia, Spain; G. Castellano, UniversidadCatolica de Valencia, Spain

The existence of single-wall carbon nanotubes (SWNTs) in organicsolvents in the form of clusters is discussed. A theory is developedbased on a bundlet model for clusters describing the distribution

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 27

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania28

function of clusters by size. The phenomena have a unified explana-tion in the bundlet model of a cluster, in accordance with which thefree energy of an SWNT involved in a cluster is combined from twocomponents: a volume one, proportional to the number of moleculesn in a cluster, and a surface one, proportional to n^(1/2). The bundletmodel for clusters enables describing the distribution function ofSWNT clusters by size. The droplet model is formally analogous tothat for clusters of fullerenes. From geometrical differences the mod-els predict different behaviours. Model yields activation barrier andpredicts that pores with radius below certain critical value are unsta-ble, while those above this radius will grow indefinitely until mem-brane ruptures.

(NANO-015) Iron-Filled Carbon Nanotubes Arrays synthesized byFloating Catalyst Chemical Vapor DepositionJ. Cheng*, X. Zou, Beijing Information Science and TechnologyUniversity, China

In this paper, we report floating catalyst chemical vapor deposition(FCCVD) for synthesizing iron-filled carbon nanotubes arrays. Weutilized ferrocene as catalyst precursor to synthesize carbon nan-otubes by FCCVD. The FCCVD setup consists of two-stage furnacefitted with independent temperature controllers, carbon source sup-ply system, carrier gas supply system and pump system. The ethanolwas introduced into furnace tube by bubbling liquid ethanol undercarrier gas flow of 100sccm 3%H2/Ar and 100sccm N2. Catalyst pre-cursor ferrocene was place at low temperature (300 degree C) region.Then ferrocene gas was introduced into high temperature (higherthan 850 degree C) region by carrier gas. Ferrocene was decomposedto form iron nano-particles as catalysts. These catalysts catalyzed thegrowth of carbon nanotubes which were deposited on substrates andthe wall of furnace tube. After about 3h synthesis time, we obtainedmass production of carbon nanotubes.

(NANO-016) Anodic Alumina Membranes as Nanoreactors forPreparation of Magnetic NanowiresK. S. Napolskii*, I. V. Roslyakov, A. A. Eliseev, A. V. Lukashin, Y. D. Tretyakov,Moscow State University, Russian Federation; S. V. Grigoriev, PNPI, RussianFederation; N. A. Grigorieva, St-Petersburg SU, Russian Federation; H.Eckerlebe, GKSS Forschungszentrum, Germany

Anodic aluminum oxide (AAO) membranes formed by two-step an-odization technique are well-known to possess uniform pore struc-ture with hexagonal arrangement of cylindrical channels and narrowpore size distribution. Combination of unique porous structure withhigh thermal, mechanical and chemical stability makes AAO ex-tremely attractive as a material for various applications in the fields offiltration, storage, sensing, and the synthesis of one-dimensionalnanostructures. In this work AAO films were used as template mate-rial for preparation of highly anisotropic magnetic nanostructures.The metal nanowires (Ni, Co and layered Ni/Cu particles) were pre-pared by electrodeposition technique. Nanocomposites were charac-terized by chemical analysis, TEM, SEM, XRD, small angle polarizedneutron scattering and SQUID magnetometry. Control of composi-tion and morphology of nanoparticles enables to predetermine mag-netic properties of nanocomposites. This work is supported by RFBR(06-03-89506, 06-03-33052).

(NANO-017) Combustion Synthesized Nickel AluminideReinforced with Ni-coated Carbon NanotubesL. Groven*, J. Puszynski, South Dakota School of Mines & Technology, USA

Combustion synthesis and in-situ densification of NiAl reinforcedwith Ni-coated carbon nanotubes has been investigated. The utiliza-tion of coated carbon nanotubes was explored as a way of enhancinginterfacial adhesion between the intermetallic matrix and carbonnanotubes. These results are compared to properties of compositessynthesized with uncoated carbon nanotubes under the same pro-cessing conditions. It has previously been demonstrated that un-coated carbon nanotubes survive the high reaction temperatures as-sociated with this type of synthesis, however the interfacial adhesion

was not satisfactory. The effect of CNT addition on product density,morphology, and mechanical properties will be discussed in detail.The extension of this work to other materials formed in a combustionsynthesis mode will be addressed as well.

(PROC-001) Synthesis and characterization of Si/Si2N2O/Si3N4composites from solid-gas precursor system via CVDJ. C. Flores-García, A. L. Leal-Cruz, M. I. Pech-Canul*, Cinvestav Saltillo,Mexico

The synthesis of Si/Si2N2O/Si3N4 composites processed via chemicalvapor deposition (CVD) using a solid-gas precursor system was in-vestigated. In this method key gas species are produced from the ther-mal decomposition of a solid precursor in the reacting system. Cylin-drical preforms (3.2 cm in diameter x 3 cm long) with 50 % porositywere prepared by the uniaxial compaction of Si powders with averageparticle size of 12.4 microns. The preforms were placed in the centerof a cylindrical CVD reactor and heated in high purity (HP) nitrogenat a rate of 15 oC/min up to a test temperature of 1300 oC. The spec-imens were maintained isothermally for 70 min and then cooleddown to room temperature. Results from the characterization byXRD and SEM show the deposition of Si2N2O and Si3N4 on the Siparticles. Si3N4 is typically deposited with a sponge-like structurewhile Si2N2O is formed with a pin-like morphology.

(PROC-002) Effect of Carbon Content on the Strength ofPressurelessly Sintered Zirconium Diboride – Silicon CarbideCeramicsM. J. Thompson*, B. Fahrenholtz, G. Hilmas, S. Zhang, Missouri Universityof Science and Technology, USA

Zirconium diboride ceramics containing 30 volume percent siliconcarbide were densified by pressureless sintering. Carbon, in amountsranging from 1.75 wt.% to 5 wt.%, was used as a sintering aid. Thecarbon reacts with and removes oxygen impurities present on thesurface of the non-oxide ceramic powder particles. Oxide impuritiescause coarsening, which inhibits densification. The zirconium di-boride – silicon carbide ceramics were characterized to understandthe effect of carbon additions on sintering behavior based on analysisof density, hardness, failure strength, grain size, and residual carboncontent.

(PROC-003) Investigation on sintering behavior and physicalProperties of Three-Layered Alumina Based NanocompositesS. Mirhashemi*, H. Baharvandi, MUT university, Iran; H. Abdizade, Tehranuniversity, Iran; N. Ehsani, MUT university, Iran

The low fracture toughness of ceramics is their main drawback. Oneof the most promising solution is production of multilayer ceramiccomposite. High hardness, wear resistance,…are the most importantcharacteristics of Alumina . Zirconia is a common reinforcement ad-ditive for Alumina matrix composites. In this research, three layer ofalumina base nanocomposite samples were made with in meddlelayer that X is 5 and 10 volume percent of Zirconia. For making ofthis samples, cold isostatic press was used. The green articles wereconventionally sintered at 1450,1550 and 1650 for three hours. Fi-nally, the sintering behavior and physical properties of compositesamples were investigated. One of the most important conclusion isthat increasing the amount of additive has a suppression effect on thegrain growth of Alumina ceramics. Also hardness is redusing by in-creasing of the volume percent of Zirconia at the inner layers of thesemultilayer samples.

(PROC-004) Pressureless Sintering of Al2O3- Carbon NanotubeCompositesS. Zhang*, W. Fahrenholtz, G. Hilmas, Missouri University of Science andTechnology, USA; E. Yadlowsky, C. Klepper, Hy-Tech Research Co. , USA

Composite powders of CNTs and Al2O3 were synthesized using anin-situ approach and then densified by pressureless sintering. Thesintered CNT-Al2O3 materials had a lower flexure strength and a bet-ter fracture toughness, compared to pure Al2O3 materials. To study

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 28

Su

nd

ay P

M

www.matscitech.org 29

the effect of CNT content and mixing method on the mechanicalproperties, a commercial CNT was purified and dispersed in anAl2O3 powder slurry, followed by freezing drying, uniaxial dry press-ing, and densified by pressureless sintering at 1600°C in flowing Aratmosphere. The results indicated that CNT- Al2O3 compositescould be pressurelessly sintered to > 95% of theoretical density forCNT contents< 3 vol.%. The flexure strength of CNT-Al2O3 materi-als decreased from 271 MPa for pure Al2O3 to 244 MPa for Al2O3containing 2.8 vol.% CNTs. Over the same composition range, thetoughness increased from 2.7 MPam1/2 to 4.1 MPam1/2. The im-proved fracture toughness of the CNT-Al2O3 materials was attrib-uted to CNT pullout and cracking bridging.

(PROC-005) Oxidation of ZrB2-SiC ceramics in dissociated airplasma and low pressure air conditionsS. Zhu*, W. G. Fahrenholtz, G. E. Hilmas, Missouri University of Science andTechnology, USA; J. Marschall, SRI International, USA

Zirconium diboride ceramics containing 30 vol% silicon carbidewere oxidized at low pressure (0.1 atm) in the highly-dissociated airplasma stream of a 1.2 MW Plasmatron wind tunnel and in air in alow-pressure furnace environment, respectively. The surface andcross-sectional morphology changes of the oxidized specimens werecharacterized and compared. When oxidized in the furnace, the sur-face of the specimens was only partially coated by a glassy layer,whereas coverage was more complete for the specimens oxidized inthe Plasmatron. Thermodynamic calculations show that the vaporpressure of SiO over SiO2 is higher in molecular oxygen than in thedissociated oxygen environment of the Plasmatron at comparabletemperatures, suggesting more rapid SiO2 vaporization during thefurnace tests than during the Plasmatron tests. X-ray diffractionanalysis and x-ray photoelectron spectroscopy indicated that nitro-gen atoms may be present in the oxide scales formed during airplasma exposure.

(PROC-006) Microstructure and failure behavior of dissimilarresistance spot welds between low carbon and dual phase steelsM. Pouranvari, Islamic Azad University of Dezful, Iran; M. Mousavaizadeh,Tarbiat Modaress University, Iran; P. Marashi, Amirkabir University ofTechnology, Iran; M. Goodarzi, Iran University of Science and Technology,Iran; H. Bahmanpour*, Wayne State University, USA

Because of various applications of dissimilar resistance spot weldsand limited publication dealing with mechanical behavior of them,there is clearly a practical need of failure behavior investigation fordissimilar resistance spot welds. The objective of this research is to in-vestigate and analyze failure behavior of dissimilar resistance spotwelds between low carbon steel and dual phase (DP600) steel. Mi-crostructural investigations, microhardness tests, quasi-static tensile-shear tests were conducted. Mechanical behavior was described bypeak load, failure energy and failure mode.To better understanding offailure path and failure mechanism, cross sections of completely andpartially fractured spot welds were examined after quasi-static ten-sile-shear test. It was concluded that the fusion zone size is the maincontrolling parameters of weld mechanical properties in terms ofpeak load, energy absorption and failure mode.

(PROC-007) Microstructural Changes due to the Friction StirProcessing of IN 738 Superalloy and Its Contribution to the GrainBoundary LiquationM. Mousavizade, F. Malek Ghaini, Tarbiat Modares University, Iran; H.Bahmanpour*, Wayne State University, USA; M. Torkamany, A. Abdollah-zadeh, Tarbiat Modares University, Iran

The effect of friction stir processing (FSP) on the microstructure ofInconel 738 superalloy and the role of this modified microstruc-ture on the grain boundary liquation susceptibility was examined.Laser surface melting was used for assessing the liquation suscepti-bility. The intense plastic deformation and thermal exposure thematerial undergoes during FSP, result in a significant microstruc-ture evolution such as grain refining and size reduction and redis-

tribution of secondary solidification constituents. Microstructuralchanges due to the FSP, for instance, small second phases and finegrains structure, provide a crack resistant microstructure to the ex-tent required for the complete suppression of grain boundary li-quation cracking.

(PROC-008) Metallurgical factors affecting failure mode ofresistance spot weldsM. Pouranvari, Islamic Azad University of Dezful, Iran; P. Marashi, AmirkabirUniversity of Technology, Iran; M. Goodarzi, Iran University of Science andTechnology, Iran; H. Bahmanpour*, Wayne State University, USA

The effect of metallurgical factors (e. g. weld microstructure) on thefailure mode of resistance spot welds is studied. The present paper in-vestigates failure behavior of resistance spot welded low carbon,HSLA and dual phase steels. To better understanding of failure pathand failure mechanism, cross sections of completely and partiallyfractured spot welds were examined after quasi-static tensile-sheartest. In the light of failure mechanism, a simple analytical model isproposed to estimate minimum fusion zone size to ensure pull outfailure mode of resistance spot welds during tensile-shear test. Ac-cording to this model, ratio of fusion zone hardness to pullout failurelocation hardness and volume fraction of porosity in the fusion zoneare the key metallurgical factors governing failure mode of spot weldsduring tensile-shear test, in addition to sheet thickness. Finally, theproposed model is compared with experimental results.

(PROC-010) Effect of Different Sub-Zero Treatments on the WearResistance of AISI D2 SteelD. Das, Bengal Engineering and Science University, Shibpur, India; K. K. Ray,Indian Institute of Technology - Kharagpur, India; A. K. Dutta*, BengalEngineering and Science University, Shibpur, India

The influence of different sub-zero treatments on the wear resistanceof die/tool steels has been analyzed by a comparative study of thewear behavior of AISI D2 steel specimens, which are subjected toconventional treatment and different sub-zero treatments: namely,cold (198 K) and cryogenic (77 K) treatments. Wear behavior of thedifferently treated specimens has been determined by sliding weartests, supplemented by microstructural characterizations and hard-ness measurements. The obtained results assist to infer that both thesub-zero treatments improve wear resistance considerably comparedto conventional treatment. However, the improvement in wear resist-ance by cryogenic treatment is significantly higher than that achievedby cold treatment. Microstructural studies reveal that cold treatmentreduces the amount of retained austenite, while cryogenic treatmentalmost completely removes it and also increases the amount of sec-ondary carbides resulting into higher hardness and wear resistance.

(PROC-011) Effect of the Ni Particle Size on the High-EnergyMilled Mixtures of Ni and Al PowdersE. T. Kubaski*, University of Sao Paulo - Escola Politecnica, Brazil; F. A.Farias, L. B. Mendes, O. M. Cintho, Universidade Estadual de Ponta Grossa,Brazil; J. T. Capocchi, University of Sao Paulo - Escola Politecnica, Brazil

It has been known that NiAl compound formation takes placethrough an exothermic reaction during high-energy milling of Niand Al powders. Since it is still unknown how milling parameters canalter the ignition time of this reaction, an investigation was con-ducted to clarify how variables such as diameter of starting powders,ball-to-powder ratio and process control agent (PCA) affect the igni-tion time. The millings were performed in a Spex 8000M Mill that al-lows to measure the evolution of jar temperature during milling,under argon atmosphere, according to a factorial design at 2 levelswith 4 variables. The as-milled powders were characterized using X-ray diffraction (DRX), scanning electron microscopy (SEM). The re-sults have indicated that when smaller Ni powder, greater ball-to-powder ratios and no PCA were used the ignition time tends to bedecreased. SEM images indicated that Ni particles deform first whenthey a greater than the Al ones, besides being harder than the Al ones.

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 29

Su

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania30

(PROC-012) The microstructure of AZ31 flake fabricated by rapidsolidification and mechanical property of extruded flakeK. Jin Woo*, K. Dea Hwan, L. Su Gun, Gyeongsang National University ,South Korea

Mechanical propertes of Mg alloy can be improved through the grainrefinement.Rapidly solidification is one of the grain refinementmethods.In this study we invested the microstructure and mechanicalpropertyof the AZ31 flake which was fabricated by rapid solidifica-tion that melt spinning was applied to with gas atomizer. The flakeshave refined grain size of 2~3μm less fraction of Mg17Al12 phase wasobserved than as cast AZ31 because the amount of Al in Mg matrixare more than that of AZ31.There is not big difference in hardness be-tween as cast and flakes.This reason is why Mg17Al12 phase tostrengthen the hardness but the flakes have low Mg17Al12 fractionand solution hardening.Comparing with as cast and flake extrusionbar, the later showed that outstanding properties both tensile strengthand elongation. These better properties result from active dynamicrecrystallization that by inner stress of flake and PSN effect of uni-form distribution Mg17Al12.

(PROC-013) Microcharacterization of Al-B-Cu-Mg CompositesSubject to Mechanical Wear and AbrassionR. Hidalgo*, N. Plaza, A. Callejo, O. Suárez, University of Puerto RicoMayagüez Campus, USA

A new series of high strength, lightweight aluminum matrix compos-ites reinforced with AlB2 particles were developed for machineryparts intended for aerospace applications. The objective has been toinvestigate the hardening effect of reinforcing AlB2 dispersoids at dif-ferent levels of boron to provide a base material for centrifugal cast-ing processing of functionally-graded composites. It is intended to es-tablish the optimal manufacturing conditions based on chemicalcomposition and heat treatment parameters. Hardness tests as well aspin-on-disk wear experiments, where the sliding distance, the appliedload and the sliding speed are readily controlled, have been used tosimulate the composite response in service. Complementary tech-niques will eventually permit developing a model to predict the mate-rial wear response as a function of the volume fraction of phases pres-ent and the composite chemical composition, permitting to calculatethe wearing coefficient.

(PROC-014) Optimization of Insert Edge Preparation in CuttingTool Development Using FEM SimulationS. Bontha*, T. J. Long, Kennametal Inc, USA

In the development of cutting tools, insert edge preparation is givenconsiderable importance owing to its effect on the performance ofthe tool. In particular, edge preparation influences the distribution oftemperature and stresses on the tool and thereby its performance.Therefore, optimization of the edge preparation for different work-piece materials and cutting conditions is an important step in cuttingtool development. However, these optimization studies generally re-quire the manufacture and testing of a large matrix of tools, which re-sult in an increase in product development time and cost. In this re-gard, finite element analysis (FEA) can be an effective tool to optimizethe edge preparation for different workpiece materials under variouscutting conditions, thereby reducing the time and cost for develop-ment. This study presents FEA results for identifying the optimumedge preparation when machining different workpiece materials. TheFEA results were also validated by lab tests.

(PROC-016) Low Temperature Oxidation Behavior of Zr-Nb-TiAlloys in AirC. J. Parga*, J. A. Ventura, S. K. Varma, University of Texas at El Paso, USA

The Zr-10Nb-10Ti and Zr-10Nb-20Ti at.% alloys have been subjectto both short term oxidation (STO) for 24 hours and long term cyclicoxidation (LTCO) up to 168 hours at a given temperature. Oxidationexperiments have been conducted in air at low temperatures between400 to 700°C. Oxidation curves for STO and LCTO involves measur-

ing the weight gain per unit area as a function oxidation temperatureand as a function of time, respectively. Oxidized products at 700°Cappear to be completely powder in both alloys. Disintegration intopowder begins at 600°C for 20Ti at.% alloy. At lower temperatures thealloys are fairly, comparatively, oxidation resistant exhibiting a thinoxide layer at the surface. The oxidation curves and oxidation mecha-nisms will be discussed for both cases. Oxidized products have beencharacterized by SEM, AEM, EDS on SEM and XRD.

(PROC-017) Process to Increase Fatigue Life of MetalsD. H. Horne*, Energy Independence, USA

The wing of a weary aircraft on it last flight to the AF disposal yard atTucson broke off over Kearns, Utah. The advertised life of another$16-mil plane on which I worked was 8K-flight hours. Thousandswere made, but fatigue cracks in critical structural members appearedat about 4K-hours. The higher, newer aircraft cost makes fleet re-placement many billions of dollars. Dr. Henry Eyring, AmericanChemical Society President, was a guest lecturer in my physical chem-istry class. He emphasized that without some energy impetus nothingchanges. This fatigue causal analysis is directed how energy levels inmetal matrixes can contribute to atom to atom bond oxidation thateventually terminates in catastrophic failures. Then Battelle tested afatigue preventive process using treated, environmentally exposeddog-bone coupons resulting in extended fatigue lives between 25xand 200x the untreated dog-bones cycles.

(PROC-018) First-Principles Elastic Constants and FormationEnergies of Ni-X (X=alloying elements) AlloysD. Kim*, S. Shang, Z. Liu, The Pennsylvania State University, USA

The Ni-based superalloys are widely used to equipments operating athigh temperatures. The effects of various alloying elements on the al-loys have attracted a lot of attention. In this study, we have performedthe first-principles calculations for probing the effect of alloying ele-ment on the elastic constants and formation energies of the dilute Ni-X binary alloys using the efficient strain-stress method and the totalenergy calculations of each structure, respectively. The supercells with31 Ni atoms and one alloying element atom were used and Al, Co, Cr,Fe, Hf, Mo, Nb, Pt, Re, Ta, Ti, W, Y and Zr were considered as an al-loying element according to the elements used. The calculated prop-erties are compared with available experimental data.

(PROC-019) Hot Forging Characteristics of Mg AlloysY. Kwon*, S. Kim, Y. Lee, J. Lee, Korea Institute of Materials Science, South Korea

Mg alloys have the highest specific strength which can be used indus-trial application. Since formability of Mg alloys is very limited, opti-mization of forming process is always needed for successful engineer-ing application. In the present study, three different Mg alloys(AZ31,AZ61, Zk60) were used for hot forging processes and several processvariables such as temperature and forging speed were investigated toimprove overall forgeability of Mg alloys. To understand the effect ofprocess variables in details, 2D-finite element analysis and forging ex-periment was performed. Three different alloys showed a similar de-pendency with forming temperature, which higher temperature ledto better formability. In the case of forging speed, a higher speedmight result in a better forging result. However, three alloys showeddifferent response to forming speed. Twinning behavior in terms offorming conditions among three alloys was found to be different,which might be responsible for the different forgeability among threedifferent alloys.

(PROC-020) Fabrication and Characterization of Squeezed CastAluminum Matrix Composites with Boride ReinforcementsL. Olaya-Luengas*, E. G. Estremera, O. M. Suarez, University of PuertoRico, USA

Aluminum-copper alloys reinforced with borides were successfullyfabricated by a squeeze casting technique employing squeezing pres-sures from 0 to 100 MPa. The distribution of reinforcements on com-posite was determined and the effect of pressure on density and hard-

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 30

Su

nd

ay P

M

www.matscitech.org 31

ness of composites was established. Besides, the borides stability wasanalyzed while the composites were heat treated. The pressure re-sponses in the composites squeezed were investigated by optical mi-croscopy, Vickers microhardness testing, Thermal Differential Analy-sis (DTA) and X-Ray Diffraction (XRD) advanced techniques.

(PROC-021) Effective Properties of MagnetoelectroelasticComposites with Interfacial CrackingB. Wang*, The University of Sydney, Australia

An impermeable interfacial crack problem in two dissimilar magne-toelectroelastic half planes has been solved in a compact form byStroh formulism. The expression for energy release rate has been de-rived. By using the expression, the overall average properties of thecomposite have been established in relation to the interface crackdensity. Results indicate that the presence of interface cracks, as awhole, would deteriorate the coupling effects in the magnetoelectro-elastic composites.

(PROC-022) Fatigue and Toughness of Niobium-Silicon AlloysD. Herman*, J. J. Lewandowski, Case Western Reserve University, USA

Advanced aerospace materials continue to be developed in order toaddress the continuing need for high temperature materials that re-tain high strength at high temperatures. An important property ofany high temperature aerospace engineering material is its resistanceto fatigue crack growth and toughness both at room temperature andelevated temperatures. In this work, the Center for Mechanical Char-acterization of Materials at CWRU and the unique equipmenthoused therein is being utilized to mechanically evaluate the fatiguecrack growth properties of advanced Niobium Silicon alloys. Theposter will present experimental work that has been performed to de-termine the fatigue crack growth resistance and toughness of these al-loys at room temperature and high temperatures. Detailed examina-tion has been performed on the alloys in order to correlate themechanical properties to the microstructures. Analysis includedScanning Electron Microscopy and Laser Confocal Microscopy.

(PROC-023) Fabrication and Mechanical Testing of FLYASH-EPOXY CompositeD. Bartwal*, College of Technology, Pantnagar, India

Addition of filler particles in small volume sections led to the increasein mechanical properties of the composite materials. Materials: Thematrix material used for the fabrication of the composite consisted ofepoxy resin and corresponding hardener. Resin and hardener weremixed in the ratio of 10:1 by weight. Wear Test: This test was per-formed on the Plint wear testing machine to study the wear charac-teristics of the composites. Impact testing: Izod and Charpy tests wereconducted to determine the impact strength of the materials. Conclu-sion: Based on the above study that critically reveals the nature of thecomposite material; it can be concluded that addition of filler parti-cles in small volume fractions led to the decrease in the compressivestrength.

(PROC-024) Consolidation of Mechanical Alloyed Ti-AlIntermetallic Compound by Electro Discharge SinteringH. Jang*, W. Lee, T. Kang, Y. Jo, Sejong University, South Korea

This study investigated the consolidation of mechanical alloyed Ti3Alpowder by EDS. It is found that the microstructure process of the Ti-Al alloying process and sintering condition can control the mi-crostructure of alloying. The sinteried powder is carried out at the450μF capacitor with a compaction pressure of 10kgf. These powderswere consolidation into a solid bulk of Ti3Al in less than 300μsec bydischarging a high voltage, high density current pulse through thepowder column. Specimens with high densities and approaching theequilibrium state can be obtained in short time by electro dischargesintering. Such shorter high temperature is important to preventgrain growth.

(PROC-025) Effect of Load Direction on Plain Woven CFRP inFracture Toughness EvaluationM. Kang*, H. Kim, S. Kim, J. Koo, C. Seok, Sungkyunkwan University,South Korea

Recently, carbon fiber reinforced polymer(CFRP) composite materi-als are widely used in various fields of engineering because of its ad-vanced properties. Specially, woven CFRP composites are fabricatedfrom carbon fibers with 2 orientation angle(0°/90°). That influencesthe mechanical properties of CFRP composite materials. So, wovenCFRP shows the different fracture behavior according to load andfiber direction. Therefore, there need to consider fracture behavioraccording to load and fiber direction at designing structure by usingwoven CFRP materials. In this paper, the fracture toughness andresidual strength for plain woven CFRP composite materials evalu-ated under three different angle condition(load to fiberangle:0°,30°,45°). The test was performed under three different anglecondition according to the standard of ASTM D3039, E399. An effectof the fracture toughness and residual strength on variation of theload and fiber direction was confirmed for woven CFRP composite.

(PROC-026) Study on Effect of Incorporation of SiC Fillers onTensile and Flexural Behavior of GV Composites by Experimentaland Simulation MethodsS. Murthylal, S. K. Venkatachar, A. Nathan*, S J College of Engineering, India

Characterization of engineering properties is a complex issue forfiber- reinforced composites due to their inherent anisotropy and inhomogeneity. In terms of mechanical properties, advanced compositematerials are evaluated by a number of specially designed test meth-ods. In this study the incorporation of SiC fillers on Mechanical be-havior of Glass-Vinyl ester (G-V) composites has been investigated.The composites are assessed by using J.J. Lloyd UTM. The tests areconducted as per ASTM standards.The results found that the tensileand flexural strength of G-V composites increased with increasingthe SiC content. Also simulation of both tensile and flexural proper-ties of GV composites with and without SiC fillers has been carriedout to validate the experimental results. The fractured surfaces of G-V composites are observed using Scanning Electron Microscope(SEM) to reveal the results.

(PROC-027) Numerical Study on Carbon Co-implant posterior toamorphization ProcessS. Park*, B. Cho, T. Won, Inha University, South Korea

It is well known that dopant diffusion during the subsequent anneal-ing process which is called TED deepens the junction depth. To re-duce these TED effects, PAI is applied before dopant implant. Re-cently, the carbon co-implant has been considered as a newimplantation technology and some studies reported that carbon co-implant after PAI process reduces TED effectively. Because carboncombines with interstitial that induces boron diffusion. In this work,we theoretically investigated the role of carbon co-implant in PAIprocess. We used BCA code for implantation and annealing is fol-lowed by KMC method. Si PAI induces amorphization to reduceboron channeling and carbon co-implant form complex with inter-stitial. As a result, we can know that carbon co-implant reduce the in-terstitial near surface and boron diffusion is retarded. We concludethat carbon co-implant reduce boron diffusion more effectively thancarbon-free Si PAI case.

(PROC-028) Advantages Caused by Orientation Effects in Piezo-composites based on Relaxor-ferroelectric Single CrystalsV. Y. Topolov*, A. V. Krivoruchko, Southern Federal University, RussianFederation

The dependence of electromechanical properties in relaxor-ferroelec-tric single crystals (SCs) on the orientation of their crystallographicaxes (X,Y,Z) stimulates use of these materials in modern piezo-com-posites. The aim of this study is to analyze effective piezoelectricproperties and hydrostatic parameters of the 2–2 and 1–3 SC / poly-mer composites comprising either PMN–xPT or PZN–xPT SCs with

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 31

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania32 MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania

certain orientations of X, Y, and Z and compositions near the mor-photropic phase boundary. Of particular interest are compositesbased on the [011] poled SCs: a rotation of crystallographic axes ofthe SC considerably influences hydrostatic piezoelectric coefficientsd*h, g*h, figures of merit and maxima of some effective parameters ofthese composites. Advantages concerned with maxd*h > 300 pC/N,maxg*h > 400 mV.m/N and max(d*h g*h) > 33000 1/PPa in differentstudied composites are discussed. A comparison with known experi-mental data on related composites is carried out.

(PROC-029) A Study on Failure Strength of Woven CRRPComposite Plate with Hole Subject to Remote LoadS. Kim*, J. Choi, W. Lee, M. Kang, J. Koo, C. Seok, Sungkyunkwan University,South Korea

In the manufacture of CFRP composite structures, independentcomponents are joined with those by bolts and pins. Holes for boltsand pins have an effect on the fatigue characteristic of such struc-tures, because those act as notchs in structures. Also, because load ofstructures with the joints transfers through pins and bolts, the fatiguecharacteristic of such structures are different from those with holessubject to remote load. Consequently, a study of fatigue propertiesabout pin load is very important. In this paper, Fatigue crack propa-gation of woven CFRP composite plate with a hole subject to pin loadwas characterized. For this study, specimens were producted accord-ing to ASTM D 3039. From experiments, crack propagations percycle and slopes of the stress-strain curves at regular time intervalswere obtained. And the relations among crack length and a slope ofthe stress-strain curve and damage of CFRP composite plates wereevaluated.

(SPEC-001) M/Polypyrrole/Carbon Nanotube(M=Pt,Pd,Ru,Pt/Pd,Pt/Ru,Pd/Ru,Pt/Pd/Ru) NanocompositeElectrode for Hydrogen Generation from Methanol andEthylene GlycolI. J. Arellano*, K. P. Badrina, M. G. Banaag, M. H. Diomampo, R. B. Leyma,University of the Philippines, Philippines

We report the synthesis, characterization and fabrication ofMetal/Polypyrrole/Carbon Nanotube (MPCNT) nanocompositeelectrode for the catalytic hydrogen generation from methanol andethylene glycol. MPCNTs were characterized via scanning electronmicroscopy (SEM) and xray diffraction (XRD) and their catalyticperformance were evaluated using cyclic voltammetry (CV). A three-electrode cell was utilized with platinum as the reference electrode,Ag/AgCl as auxiliary electrode and MPCNT as the working electrodein -0.40 to 1.0 V working range at 20mV/s. The electrolyte solutionwas an aqueous 0.50M methanol or ethylene glycol in 0.50M sulfuricacid. Results show that MPCNT where M=Pt/Pd,Pt/Ru,Pd/Ru andPt/Pd/Ru showed dramatic enhancement ranging from 50-200% rel-ative to MPCNT where M=Pt,Pd or Ru. These hold promise as an ac-tive electrode for fuel cell applications.

Monday, October 6, 2008

Keynote & Lectures

Opening Session and Keynote AddressRoom: Ballroom B/C

9:00 AMThe Role of Science and Engineering in U.S. Competitiveness(Invited)C. A. Murray*, Lawrence Livermore National Lab, USA

Against a background of increasing globalization, a blue ribbon panelwas charged with recommending actions that policymakers shouldtake to enhance the science and technology enterprise so that theUnited States could successfully compete, prosper, and be secure in

the global community of the 21st century. The result of that work isthe highly acclaimed report called Rising Above the Gathering Storm.In this keynote presentation, Dr. Murray, who was a member of thepanel, will discuss the significant findings as well as the response tothem that is shaping tomorrow’s science, engineering, and technologypolicy.

Special Topics: ACerS 110th AnniversarySymposium

ACerS 110th Anniversary SessionRoom: 404/405Session Chair: L. David Pye, Alfred University

9:50 AMHistory and Evolution of the American Ceramic Society (Invited)J. McCauley*, Army Research Laboratory, USA

The American Ceramic Society has evolved into a diverse Profes-sional Society that no one could have predicted on February 16, 1898,at the 12th meeting of the National Brick Manufacturers Associationin the Monongahela House in Pittsburgh, where a group of 9 atten-dees decided to create our Society. In those days ceramic productswere very visible commodities and starting materials were naturalrocks and minerals. Wars, consumer needs and technical innovationshave had an enormous impact on the ceramic industry. More re-cently, the globalization of the market place and professional soci-eties, the emergence of materials science and engineering as an edu-cational discipline, as well as the formation of new societies has haddramatic impacts on ACerS. Particularly challenging is that those“visible” commodities in the beginning are now being increasinglymanufactured over seas and our modern ceramics, many of which aremade from synthetic starting materials, are hidden in consumerproducts.

10:20 AMThe Eleven Best Papers in 110 Years (Invited)S. K. Sundaram*, Pacific Northwest National Laboratory, USA; D. Pye, AlfredUniversity, USA; J. A. Kaniuk, Zircoa, Inc., USA; K. T. Faber, NorthwesternUniversity, USA

The American Ceramic Society (ACerS) celebrates its 110th Anniver-sary in 2008. Since it’s founding in 1898, it continues its century-oldmission to serve the international ceramics community in manyways. We will gather again in Pittsburgh on October 6, 2008 to cele-brate this milestone. On this occasion, we will be selecting and honor-ing the 11 best papers published in the Journal of ACerS during 11decades of continuous operation of the Society (February 2008 issueof the Bulletin (www.ceramicbulletin.org)). Please click the linkbelow to nominate a paper or papers:http://www.surveymonkey.com/s.aspx?sm=QTdu2cJ6JRu3cA98c4PNNg_3d_3d. On October 6, 2008, the organizer will make a presenta-tion highlighting the selection process and identifying the selected 11papers and announce the papers at the ceremony. All ACerS membersand MS&T 2008 attendees are invited to this exciting event to remi-nisce our glorious past and look ahead into many more decades ofservice and excellence.

11:10 AMCeramic and Glass Opportunities in the NAE’s Grand Challengesfor Engineering in the 21st Century (Invited)K. T. Faber*, Northwestern University, USA

Ceramic scientists and engineers contributed significantly to thegreat engineering achievements of the 20th century ranging fromlaser and fiber optics to ceramic substrates for electronic packaging.See, for example, www.greatachievements.org. As a follow-on, theNational Academy of Engineering announced its grand challenges forengineering in the 21st century. Materials opportunities abound in

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 32

Mo

nd

ay A

M

www.matscitech.org 33

addressing environmentally friendly power to clean water to an im-proved urban infrastructure. We report on ACerS members’ views ofwhat are the most important of the grand challenges, based upon anACerS survey. A panel of NAE members who are also ACerS memberswill comment on how ceramics and glass can be designed and/orused to meet these grand challenges.

Special Topics: Education and ProfessionalDevelopment

Education Trends and MethodsRoom: 403Session Chair: William Fahrenholtz, Missouri University of Scienceand Technology

9:40 AMOutcomes of the Future of MSE Education Workshop (Invited)I. Robertson*, University of Illinois at Urbana-Champaign, USA; C. Singh,University of Pittsburgh, USA; R. J. Hamers, University of Wisconsin, USA

In August 2008 a workshop on the future of materials science and en-gineering education was held. The scope was broad ranging from ed-ucating the general public to undergraduate and graduate education.The goals were to development recommendations to increase aware-ness of and participation in the discipline, and to define the coreknowledge base for baccalaureate and doctoral degree programs. Thelatter is an especially challenging task as the field is broad as materialsscience and materials engineering now occurs in most engineeringdisciplines, and in chemistry and physics. This talk will highlight thefindings and recommendations of the workshop.

11:00 AMUpdate on ABET Accreditation ActivitiesE. Judson*, Georgia Institute of Technology, USA; J. W. Fergus, AuburnUniversity, USA; G. Bond, New Mexico Tech, USA

An update on ABET related accreditation activities will be presented.Recent and proposed accreditation criteria changes will be reviewed.Changes in the evaluator training process will be presented. Discus-sion on satisfying the culminating major design experience criteria inmaterials and ceramic engineering will be a particular focus.

11:20 AMThe Design and Performance of Intermediate ConstraintQuestions for Assessing Student PerformanceP. R. Howell*, J. Sturgeon, R. DeFrain, The Pennsylvania State University, USA

The assessment of an introductory course in Materials Science in-volves a series of twelve, on-line, low-stakes, open-book quizzes. Thequizzes rely on a question database, which is based on multiple-choice type questions, and student responses are automaticallygraded. Both as a response to critics who complain of excessive use ofmultiple choice questions and in an attempt to increase the effective-ness of the course in promoting scientific literacy, we have exploredthe use of questions that require students to make not one responseon test questions, but several responses to tightly related or complexquestions. We will present information about these “intermediateconstraint” questions, and show how these question types add to theevaluation of student progress.

11:40 AMFederation for International Refractory Research and Education(Invited)J. Smith*, Missouri University of Science & Technology, USA

The Federation for International Refractory Research and Education(FIRE) was established to promote refractory education on a globallevel. The federation is a network of academic and industrial partnersthat support graduate educational opportunities and exchanges be-

tween global centers of excellence in refractory engineering and sci-ence. The increasingly global nature of the refractory industry neces-sitates that new employees be aware of, and prepared to function in, aglobal arena. FIRE certificates are awarded to students that have notonly excelled in their graduate studies but who have also participatedin at least one global exchange during their graduate career.

12:00 PMMaterials Science and Engineering Education: An Open Letter tothe Materials CommunityL. M. Bartolo*, Kent State University, USA; I. Robertson, A. Powell, Universityof Illinois - Urbana Champaign, USA; T. Osman, TMS, USA

Materials education faces many challenges. As part of the larger scien-tific and engineering community, we are impacted by the “GatheringStorm” challenges and “Engineer of 2020” issues. We also have ourown unique set of challenges, including fewer materials department;expansion of programmatic areas from traditional metallurgy and ce-ramics to include semiconductors, polymers and more recently bio-materials; as well as the increasing participation of other disciplinesin materials research and education. The paper seeks to highlight thechallenges facing materials education today, offering suggestions foractions that engage academia, industry, government agencies andprofessional societies in developing the next generation of materialsscientists and engineers.

Electronic & Magnetic Materials: Copper andCopper Based Alloys in the ElectronicsIndustry

Copper and Copper Based Alloys in the ElectronicsIndustry IRoom: 315Session Chair: Larry Wojnicz, Molex Incorporated

9:40 AMCopper Nickel Silicon Alloys for High Density Processor Sockets(Invited)P. W. Robinson*, J. E. Gerfen, Olin Brass, USA

Miniaturization in electronic products is placing ever increasing de-mands on all materials and copper alloys are no exception. The needto provide more I/O’s in the same or smaller footprint results in com-puter processor sockets being among the most demanding applica-tions for copper alloys. Copper nickel silicon alloys have receivedwidespread acceptance as the solution to today’s demands – but whatabout tomorrow. The paper will briefly review the drivers which pushcopper alloy requirements to thinner gage, higher yield strength withat least equivalent formability and electrical conductivity. Metallurgyand properties of an existing copper nickel silicon alloy C7025 will becontrasted with C7035 which is a newly developed material basedupon the same alloy system. This alloy will satisfy demands past theend of the current decade, but further improvements will then be re-quired. Early development efforts toward these improvements willalso be outlined.

10:00 AMNew Generation Copper Alloys and Tin Coatings for ConnectorApplications (Invited)A. Kamf*, Luvata, USA

New generation automotive connectors are phasing enhanced per-formance requirements but also high cost of copper. It is expectedthinner material will be used, with increased demand on the copperalloys and coatings also at elevated temperatures. The connectors canhave many terminals. During assembly the friction properties of thecoatings are of importance to reach lower insertion force. New alloysand coatings with enhanced performance have been developed at

001_271.MST_Abstract.4th 9/3/08 3:05 PM Page 33

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania34

Kobe Steel, Ltd and licensed by Luvata. Stress relaxation resistanceand formability were examined for the alloys. Contact properties andsolderability before and after exposure to elevated temperatures wereevaluated using contact resistance and wetting balance. Simulated in-sertion and measurements of coefficient of friction were performedin a laboratory test rig, using ball on flat configuration. The resultsshow that the new products are suitable for use at temperatures above150 degree Celsius.

10:20 AMDevelopment of Innovative Copper Alloys for Electronic Devices(Invited)N. Yuki*, Nippon Mining & Metals, Japan; T. Ono, Nippon Mining & MetalsCo., Ltd., Japan; K. Fukamachi, Nippon Mining & Metals, Japan

Since copper and copper alloys have both excellent mechanical prop-erties and high electrical conductivity, they have been used as func-tional materials for electronic devices such as connectors, lead framesof IC packages and FPCs. A trend toward higher performance, higherreliability and higher-density packaging of electronic devices particu-larly for IT equipments continues to be strong. Therefore, metallicmaterials are being required to show higher performances even withthinner gages. To fulfill the requirements, we have developed a clusterof Innovative Copper Alloys for Electronic Devices. The alloys areC52400 (GH), NKT322 (GIGALLOY), and NKC388 for connectors,NKC1816 for CPU sockets, C70250 (GH) for lead frames, and HA forFPCs. In this paper, the concepts of alloying and processes of the alloyswill be presented as well as the mechanical and electrical properties.

11:00 AMInlay Clad Metal for High Temperature Connector ApplicationsL. Chen*, B. Njoes, D. Williams, Technical Materials, Inc., USA

Recent new designs for telecom and automotive electronics demandmore reliable connectors at higher temperatures in adverse environ-ments. The essential requirements for the connector materials in suchlow voltage applications include stable low surface electrical contactresistivity, sound corrosion resistance in the service conditions andhigh wear resistance if sliding contact is involved. A Cu-alloy basemetal with an ultra-thin AuPdAgNi diffusion-alloyed inlay has beenstudied. Contact electrical resistivity was evaluated experimentally onthe AuPdAgNi inlay in the Cu-alloy clad metal after exposure in air at175°C and 200°C as well as in humidity with a cyclic temperature.Different Au-electroplating Cu-alloy samples were included in thestudy for comparisons. The two coating systems, inlay and electro-plating, showed different behaviors in contact electrical resistivity vs.the time, with the AuPdAgNi inlay system being more stable. Charac-terizations of the tested samples were performed.

11:20 AMFatigue Behavior, Strength, and Structural Evolution of Cu-15Ni-8Sn with Heat TreatmentJ. Caris*, R. Varadarajan, J. J. Lewandowski, Case Western Reserve University,USA; J. J. Stephens, Sandia National Laboratories, USA

Certain spring applications require a material with a combination ofhigh strength, stiffness, and electrical conductivity. An alloy consist-ing of Cu-15wt%Ni-8wt%Sn (C72900) is one of several copper basedalloys which can be heat treated/processed to form a metallic nano-structured alloy with good combinations of yield strength and elec-trical conductivity. Tensile and flexural fatigue properties of the vari-ous heat-treated conditions will be compared with observed fracturesurfaces and microstructures in an effort to identify the failure mech-anisms of the various time and temperature evolved microstructures.Optical metallography, TEM, and XRD spectra are included in orderto map the evolution of specific micro- and nano-structural featureswith various heat treatments. Support for this research has been pro-vided by the National Physical Sciences Consortium and Case PrimeFellowship.

11:40 AMSUPRALLOY: A New High Performance Bronze (Invited)S. J. Gross*, F. Bubeck, A. Kuhn, I. Buresch, Wieland-Werke AG, Germany

Consequent reduction of the grain size in traditional connector alloyslike phosphor bronzes lead to significant improved strength andformability at unchanged chemistry. As such such the new high per-formance bronze family provides properties, which so far were onlypossible when using a precipitation hardened high perfomance cop-per alloy.

Electronic & Magnetic Materials:Ferroelectrics and Multiferroics

Piezoelectric Ceramics and Thin FilmsRoom: 318Session Chair: Xiaoli Tan, Iowa State University

9:40 AMHigh Frequency Piezoelectric MEMS Devices (Invited)R. G. Polcawich, US Army Research Laboratory, USA; I. G. Mina, H. Kim, I.Kim, S. Park, K. Choi, T. N. Jackson, R. L. Tutwiler, K. Cheng, Penn State,USA; D. Judy, J. S. Pulskamp, M. Dubey, US Army Research Laboratory, USA;S. Trolier-McKinstry*, Penn State, USA

Lead zirconate titanate (PZT) piezoelectric films have been utilized toprepare two families of high frequency MEMS devices: RF switches andarray transducers. PZT films were used as the actuators for surface mi-cromachined RF MEMS switches which operate at less than 10 V whileretaining excellent isolation in the open state and an insertion loss of<0.5dB up to 40 GHz. The switching time is about 40 μs, and is limitedby bouncing. The temperature stability of the switches is good over therange from -25 °C to 100 °C. On average, the switches could handle 2 –3 W of RF power. Present commercial ultrasound array transducersoperate at 1-16 MHz, which is well-suited for the deep penetration re-quired of current clinical applications of ultrasound. We are currentlyworking to extend the frequency range and the available resolution byup to two orders of magnitude, making 1D and 2D array transducerspotentially useful for pill cameras or wireless ultrasound systems.

10:20 AMFerroelectric BaTiO3 Thin Films on Ni Metal Tapes Using NiO asBuffer LayerG. Collins*, J. Liu, J. Weaver, C. Chen, University of Texas at San Antonio,USA; J. Jiang, E. Meletis, University of Texas at Arlington, USA; V. Giurgiutiu,University of South Carolina, USA; R. Guo, A. Bhalla, University of Texas atSan Antonio, USA

Orientation preferred Ferroelectric BaTiO3 thin films were depositedon Ni tapes by pulsed laser deposition. Microstructural studies revealthat the as-grown BaTiO3 films have the nanopillar structures with anaverage size of approximately 80 nm in diameter and the good interfacestructures with no inter-diffusion or reaction. This result demonstratedthe possibility of approximating an oriented single crystalline ceramicoxide structures on metallic substrates. The dielectric and ferroelectricproperty measurements exhibit that the BTO films have a relativelylarge dielectric constant, a small dielectric loss, and an extremely largepiezoelectric response with a symmetric hysteresis loop. These excellentproperties indicate that the as-fabricated BTO films are promising forthe development of the structural health monitoring systems. ReferenceYuan Z., Liu J., Weaver J., Chen C. L., Jiang J. C., Lin B., Giurgiutiu V.,Bhalla A., Guo R. Y.APPLIED PHYSICS LETTERS, 90 (2007) 202901.

11:00 AMFundamental Processing Concepts Affecting Texture Quality inPiezoelectric CeramicsS. Poterala*, R. J. Meyer, G. L. Messing, Pennsylvania State University, USA

High quality textured piezoelectric ceramics have been producedusing the Templated Grain Growth (TGG) method. While some of

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 34

Mo

nd

ay A

M

www.matscitech.org 35

these materials show a significant fraction of single crystal proper-ties, further improvements are limited by texture quality (the vol-ume fraction of texture and the orientation distribution of alignedgrains). Magnetic Alignment (MA) has recently been used to pro-duce textured ceramics in many non-magnetic material systemsand shows great promise for improving texture quality in piezoelec-tric ceramics. In this work, fundamental processing factors thatgovern texture formation during MA / TGG processing are pre-sented. Both particle alignment and microstructure developmentmust be considered simultaneously to achieve high texture quality.Preliminary results for combined MA / TGG processing of PMN-PT will be presented, and microstructure - property relationshipswill be discussed. Financial support provided by the Department ofNaval Research

11:20 AMUnderstanding Domain Orientation Effects in PolycrystallinePiezoelectrics (Invited)K. J. Bowman*, T. S. Key, Purdue University, USA

We have explored how domains are aligned in grains of all orien-tations and how the domain alignments may change with temper-atures up to and above the original poling temperature in tex-tured and untextured piezoelectrics. This research iscomplementary to research analyzing stable domain configura-tions, research on the motion and characteristics of ferroelectricor 180° domain walls, and the very small number of in situ inves-tigations of mechanical or electrical effects on domain alignment.Our domain texture studies have advanced understanding of fer-roelastic domains by considering residual stresses induced via sur-face grinding and prior poling effects on polarization and strainhystereses in soft and hard piezoelectrics. In this presentationcontexts for further investigation of microstructure, temperatureand stress effects will be described as well as proposed considera-tions for advancing the performance of the new classes of leadfree piezoelectrics.

Electronic & Magnetic Materials:International Symposium on AdvancedDielectric Materials & Electronic Devices

Composition, Processing, Microstructure, andProperty Relationships IRoom: 317Session Chair: Danilo Suvorov, Jozef Stefan Institute

9:40 AMDielectric Properties of AA’3Ti4O12-type Perovskites (Invited)D. Sinclair*, A. R. West, M. Ferarrelli, M. Li, University of Sheffield, UnitedKingdom

In recent years there has been significant interest (and confusion!)regarding the so-called giant permittivity effect (ε > 10,000 (ceram-ics) and > 100, 000 (single crystals)at 300 K) observed at radio-fre-quencies in the unusual perovskite-related compoundCaCu3Ti4O12 (CCTO). Although it is now widely accepted that theeffect in ceramics is extrinsic and related to an Internal Barrier LayerCapacitance (IBLC) mechanism associated with the development ofSchottky barriers between semiconducting grains and insulatinggrain boundaries many questions remain unanswered. For example,what is the origin of the semiconductivity in CCTO, what is thegrain boundary phase(s) and why is the effect observed for singlecrystals? Here we present a concise summary of the electrical proper-ties of CCTO single-crystals and ceramics using Impedance Spec-troscopy. The origin of the giant permittivity is revealed to be differ-ent in each case; however, in both, it is shown to be an extrinsiceffect.

10:20 AMStructure and properties of compounds in the Sr1-3x/2CexTiO3homologous series (Invited)R. Ubic*, Boise State University, USA; G. Subodh, M. T. Sebastian, Institute ofInterdisciplinary Sciences and Technology, India; D. Gout, T. Proffen, LosAlamos Neutron Science Center, USA

Four compositions in the Sr1-3x/2CexTiO3 homologous series, cor-responding to x = 0.1333, 0.1667, 0.25, and 0.4 have been producedby conventional solid-state processing. The structure of these com-pounds was analyzed by x-ray photoelectron spectroscopy (XPS) aswell as x-ray, electron, and neutron diffraction. While no superlatticecan be observed via x-ray diffraction, both electron and neutron dif-fraction show evidence of a non-cubic supercell caused by antiphasetilting of oxygen octahedra. The most likely space group is R-3c, cor-responding to an a-a-a- tilt system, except for the composition x = 0.4for which an even more complex superstructure is observed. As ex-pected, the degree of tilt increases with increasing x. These materialshave dielectric constants in the 113-173 range, Qf values from 7800-11000 GHz, and TCF values only about 20% of that observed for pureSrTiO3.

11:00 AMRelaxor-like Behaviors and Giant Dielectric Response inLa2NiMnO6 Multiferroic Ceramics (Invited)X. Chen*, Y. Lin, X. Liu, Zhejiang University, China

Dielectric characteristics of La2NiMnO6 multiferroic ceramics wereinvestigated together with the crystal structure. The monoclinicstructure in P21/n space group was determined, where Ni2+ andMn4+ ordered periodically. La2NiMnO6 ceramics exhibited signifi-cant giant dielectric response together with the relaxor-like behavior.The dielectric relaxation in La2NiMnO6 ceramics was well fitted bythe Arrhenius law and the activation energy of 0.17 eV was obtained.The origin of giant dielectric response and electronic ferroelectricitywere discussed with respect to the charge ordering of Ni2+ andMn4+, and it was also compared with those for LuFe2O4 and otherrelated materials.

11:20 AMIncipient ferroelectricity and microwave dielectric resonanceproperties of CaCu2.85Mn0.15Ti4O12 ceramicsM. Li*, A. Feteira, D. C. Sinclair, A. R. West, The University of Sheffield,United Kingdom

Mn-doped CaCu3Ti4O12 ceramics with nominal compositionCaCu2.85Mn0.15Ti4O12 (CCMTO) have been prepared and their radio-and micro-wave dielectric properties established. At 300 K, denseCCMTO ceramics have appreciable grain resistivity, 20 MΩ cm, andexhibit microwave dielectric resonance with εr ~ 93, Qf ~ 3950 GHzat 3.95 GHz and temperature coefficient of resonant frequency ~+657 ppm/K. The magnitude of, and activation energy for, bulk con-duction in CCMTO are similar to those of the insulating grainboundaries in CCTO ceramics. It is proposed that the grain and grainboundaries regions in CCTO ceramics consist of the same phase butwith slightly different compositions. εr decreases smoothly from ~150 to 90 in the range of 10 - 300 K, obeys the Curie-Weiss law in therange of ~ 60 - 180 K, and is consistent with incipient ferroelectricity,which is the most likely origin of the higher intrinsic εr of CCTO-type materials such as CCMTO than that from calculation.

11:40 AMEffect of Dopants and Processing on the Microstructure andDielectric Properties of CaCu3Ti4O12 (CCTO)B. A. Bender*, M. Pan, E. P. Gorzkowski, Naval Research Laboratory, USA

In the past seven years exploratory research has been conducted onthe giant dielectric constant oxide CCTO. This is because the dielec-tric material has been shown to have a giant permittivity (as large as80,000) that is stable over a range of temperatures and frequencies.However, the typical CCTO ceramic usually has a dielectric loss of 0.1

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 35

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania36

or higher which needs to be reduced if this dielectric oxide is going tobe used commercially. Also CCTO has a relatively low breakdownvoltage which needs to be improved. Attempts to reduce dielectricloss and increase breakdown voltage result in a drastic reduction of itsdielectric constant. This paper explores the effect of dopants and pro-cessing in relationship to their effects on the resultant microstructureand dielectric properties of CCTO in an effort to reduce the loss ofCCTO while incurring only a modest reduction in its permittivity

Electronic & Magnetic Materials: Pb-Free, Pb-Bearing Joining and Packaging Materials andProcesses for Microelectronics

Mechanical Properties and Service Reliability ofSolders and Solder JointsRoom: 319Session Chairs: Fu Guo, Beijing University of Technology; ThomasBieler, Michigan State University

9:40 AMThe Effect of the number of Sn Grains and their Orientations onthe Shear Fatigue Life of SnAgCu Solder JointsB. Arfaei*, Y. Xing, J. Woods, J. Wolcott, P. Tumne, SUNY Binghamton, USA;P. Borgesen, Unovis-Solutions, USA; T. Bieler, Michigan State University,USA; E. Cotts, SUNY Binghamton, USA

The dependence of the room temperature shear fatigue lifetime ofSnAgCu solder joints on the number of Sn grains and orientations wasstudied. The mean fatigue lifetime was found to be longer for sampleswith multiple Sn grains than for samples with single Sn grains. For sin-gle Sn grain samples, correlations between Sn grain orientation (withrespect to the loading direction) and lifetime were examined. Thereare a few single grain samples with very early or late number of cyclesat failure, and these results will be examined with respect to their ori-entation and the number of slip systems likely to be operative. In gen-eral, the plastic deformation and strain hardening of single metal crys-tals shows distinct dependence upon their orientation, as does,ultimately, fracture. Thus, for the present SnAgCu system, correlationsbetween the type of activated slip systems and shear fatigue lifetimeswill be examined in a search for clear explanations for early failures.

10:00 AMInfluence of Nano-structured Additions on theThermomechanical Fatigue Behavior of Sn-based Solder AlloysD. Choudhuri*, A. Lee, K. N. Subramanian, Michigan State University, USA

Thermomechanical Fatigue (TMF) studies in the high temperatureregime (between -15 C and 150 C) revealed that Sn-3.5Ag solderjoints have a better residual mechanical performance than Sn-Ag-Cu.In addition, incorporation of well-bonded, non-coarsening nano-structures into Sn-3.5Ag further improved residual strength. Al-though, such nano-structures did not yield similar improvement inSn-Ag-Cu solder joints. It was documented that mechanical proper-ties and deformation mechanisms of Sn-based solders are highly tem-perature sensitive. This study reports and compares the residualstrength of solder joints made of Sn-3.5Ag, Sn-Ag-Cu, and thosemodified with nano-structure additions upon exposure to differentextent of TMF in the lower temperature regime (between -55 C and125 C). Additionally, we attempt to develop a structure-property rela-tionship by adding different concentrations of nano-structures insuch alloys, and report changes in the as-solidified microstructures.

10:20 AMImpression Creep of Pure TinR. Chen*, F. Yang, University of Kentucky, USA

In an operating electronic device, solder joints will experience creepdeformation due to the difference of the CTE between the assembly

parts and the PCB. It is very important to study the creep deforma-tion of solders to estimate the reliability of solder joints. In this work,the creep behavior of pure tin was evaluated in the temperature rangeof 30 ~ 90 °C and under the punching stress of 21 ~ 69 MPa by usingthe impression technique. A steady state was observed after a tran-sient state with the stress exponent ranged from 5.0 to 6.1. For lowstresses, a single activation energy of 35 kJ/mol was obtained, which isclose to the activation energy of grain boundary diffusion of β-tin.For high stresses, the activation energy was 35 kJ/mol for low temper-ature and 70 kJ/mol for high temperature. This suggests that at highstress, there exists two mechanisms controlling the creep deformationof β-tin, 1) grain boundary diffusion at low stress and low tempera-ture; 2) dislocation motion at high stress and high temperature.

11:00 AMNew Mechanism for Tin Whisker GrowthJ. Cheng*, University of Rochester, USA; P. T. Vianco, Sandia NationalLaboratories, USA; J. Li, University of Rochester, USA

Electroplated and evaporated Sn films were deposited on 1 inch diam-eter silicon Sn wafers precoated with a Ni/Cr layer. A 500 g point loadwas applied at the center the Si wafer circularly supported at the edgeto produce a known axially-symmetric compressive stress in the Snfilm. The setup was placed inside a vacuum oven and annealed at 160degree C for 7 days. After the annealing treatment, Sn whiskers grewfrom evaporated samples, while large hillocks grew from the electro-plated Sn samples. For both film types, the grain microstructure on topof the hillocks appeared to be similar to that of the undisturbed film.FIB analysis showed that the base of “hillocks” was directly over the Ni-coated Si substrate; there was no Sn film remaining under them. Thismorphology suggests that the Sn atoms were transported to the base ofthe hillocks along the interface between the Sn film and the Ni layer.

11:20 AMElectromigration Induced Whisker Growth in Eutectic SnBiSolder AlloyG. Xu, H. He, F. Guo*, Beijing University of Technology, China

Whisker growth on beta-tin (β-Sn) is a surface relief phenomenon. It’sdriven by a compressive stress gradient. The origin of the compressivestress can be mechanical, thermal, and chemical. Electromigration en-hances atomic diffusion in the electron flow direction by electron windforce. In the eutectic Sn-Bi solder alloy, electromigration could inducethe redistribution or segregation of Sn-phase and Bi-phase. The maindiffusion phase, Bi, is stronger than Sn. As a consequence, when the Snatoms continuously migrate toward to the anode side after Bi atomsform a barrier ahead of Sn, there will be a stress generation and relax-ation occurring in the Sn-phase, stimulating the growth of Sn whiskers.The current research effort characterizes the Sn whiskers induced fromelectromigration and discusses the contributing parameters to suchgrowth from both materials perspective of views and service conditions.

11:40 AMThickness Effect on the Whisker Growth in Pure TinY. Li*, F. Yang, University of Kentucky, USA

The whisker growth in lead-free solder has imposed a challenge inimproving the reliability and life-time of high-end electronic devices,which use the lead-free solder as electromechanical interconnections.In this work, the dependence of the stress-assisted whisker growth onthe thickness of tin-layer was studied. Thin layers of pure tin wereelectroplated on copper substrate. Local mechanical stresses were in-troduced by the indentation. Local tin-whisker growth/extrusion wasobserved surrounding the indents. The total number of the tin-whiskers surrounding the indents increased with the increase in theindentation load. The number of the tin-whiskers per unit area de-creased with the increase in the layer thickness. The whisker growthbecame more significant for thicker samples, and the length of thewhiskers increased with the increase of loads. This work is supportedby Kentucky Science and Engineering Foundation.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 36

Mo

nd

ay A

M

www.matscitech.org 37

Electronic & Magnetic Materials: PerovskiteOxides: Films, Nanostructures, Properties,and Applications

Perovskite Oxide Films and Nanostructures IRoom: 316Session Chairs: Haiyan Wang, Texas A & M University; Quanxi Jia,Los Alamos National Lab

9:40 AMGiant Piezoelectricity on Silicon for Integrated Sensors andActuators (Invited)C. Eom*, University of Wisconsin-Madison, USA

Integration of single crystal piezoelectric films on silicon offers thefabrication of high performance piezoelectric MEMS incorporatingall the advantages of large scale integration with on-board electroniccircuits. We have fabricated heterostructures with the highest piezo-electric coefficients ever realized on silicon by synthesizing epitaxialthin films of Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) on (001) Siusing an epitaxial SrTiO3 template layer. The longitudinal (d33) andeffective transverse (-e31) piezoelectric coefficients of the films areover 1200 pm/V and -29 C/m2, respectively. These are highest valuesthat have ever been reported for any piezoelectric films. These epitax-ial heterostructures can be used for multilayered high performanceMEMS and NEMS devices. This work has been done in collaborationwith S.H. Baek, D.M. Kim, H.W. Jang, R.R. Das, J. Lettieri, V.Vaithyanathan, N.B. Gharb, V. Nagarajan, Y.B. Chen, H.P. Sun, S.K.Streiffer, X.Q. Pan, S. Trolier-McKinstry, R. Ramesh, D.G. Schlom

10:20 AMInterface Engineered Multifunctional Thin Films and AnomalousPhenomena (Invited)C. Chen*, University of Texas at San Antonio, USA

Interface engineered metamaterial have attracted more and more at-tention in the functional materials research and active device fabrica-tion. It plays a key role to control the physical properties of advancedmaterials. We have focused on the systematical studies of interface ef-fects on highly epitaxial functional oxide thin films. For instance, anextremely high dielectric tunability of 80% have been achieved fromhighly epitaxial ferroelectric Mn:(Ba,Sr)TiO3 thin films from the inter-face controlled nano domain structures; strong anisotropic phenom-ena were observed in highly epitaxial (Pb,Sr)TiO3 and (La,Sr)MnO3thin films; double diffraction study reveals that the two-dimensionalin-plane interfaces of perovskite structure films on salt-rock type sub-strate is well commensurate with the MgO substrate over large areasfor (Pb,Sr)TiO3 thin films,whereas LCMO film is only locally com-mensurate with the substrate. Details will be discussed in the talk.

11:00 AMLow temperature growth of epitaxial La1-xSrxMnO3 film byexcimer laser-assisted metal organic depositionT. Tsuchiya*, T. Nakajima, T. Kumagai, National Institute of AdvancedIndustrial Science and Technology, Japan

We have developed the excimer laser-assisted metal organic deposi-tion (ELAMOD) process for the preparation of the epitaxial metaloxide film at low temperature. In this study, to clarify the epitaxialgrowth of LSMO films and improve the electrical properties, we pre-pared LSMO film on SrTiO3 substrate by using XeCl laser at 500°C,and successfully prepared the epitaxial LSMO film. To improve thetemperature dependence of the resistance (TCR) of the film, we in-vestigated the effects of repetition rate and the shot number on Tp(temperature of peak resistance), Tm (temperature of maximumTCR) and TCR (temperature coefficient of resistance) of the film. Atthe same shot number and laser fluence, the crystalinity of the LSMOdepend on the repetition rate. Using the 25rHz, epitaxial

La0.8Sr0.2MnO3 film on STO substrate grown by XeCl laser irradia-tion showed the maximum TCR of 4.7% at 275K.

11:20 AMTilt Transitions in Perovskite Films (Invited)S. Trolier-McKinstry*, D. Tinberg, R. Johnson, Penn State, USA; Y. Han, I.Reaney, University of Sheffield, United Kingdom; I. Levin, NIST, USA

Tilt transitions in perovskites occur due to cooperative motions ofthe oxygen octahedra framework. Such transitions have a profoundimpact on the temperature coefficient of resonance frequency and onpiezoelectric constants. Despite their importance, the physics of sizeeffects and the effect of mechanical constraint (as in thin films) forthese tilt transitions is poorly understood in comparison to dis-placive transitions. This paper reports on tilt in lead zirconate ti-tanate, BiScO3, SrRuO3, and ATN. For example, epitaxialAgTa0.5Nb0.5O3 (ATN) films deposited on (001)p SrRuO3/LaAlO3 andLaAlO3 by a chemical solution deposition technique have been char-acterized by transmission electron microscopy. For ATN films, onlysuperstructure reflections at 1⁄ 2{ooo} positions were observed, consis-tent with a structure tilted in antiphase only. In contrast, bulk ATNshowed ±1⁄ 4(00l) reflections which result from a combination of in-phase and antiphase tilting along the c axis as well as antiparallelcation displacements.

Environmental & Energy Issues: Ceramicsand Glass for Waste Minimization,Stabilization, and Disposition

Materials for Nuclear Applications andEnvironmental TreatmentRoom: 326Session Chairs: Connie Herman, Savannah River National Lab;Sharon Marra, Savannah River National Lab

9:40 AMInert-Matrix Fuels in Gas-Cooled Reactors (Invited)T. Lindemer*, Consultant, USA

Inert-matrix oxide fuels in gas-cooled reactors will have characteris-tics different from previous oxide fuel experience. Recently publishedthermodynamics for the Zr-Pu-O system were modeled and used todemonstrate that an in-particle SiC getter for CO is needed. RecentZr-Pu-O phase diagram information reveals that zirconia phase tran-sitions may need to be considered. In-particle retention of highercontents of Pd, Rh, and Ru fission products will also be discussed.

10:20 AMSynergistic Effects of Gamma Radiation, Elevated Temperature andAlkaline Chemistry on Modified Crosslinked Polyethylene (XLPE)K. D. Billings*, T. Skidmore, M. C. Kane, Savannah River NationalLaboratory, USA

Advances within the field of engineered polymers have begun to yieldmaterials capable of handling higher doses of radiation at highertemperatures. The chemical stability of crosslinked polyethylene(XLPE) makes it an excellent candidate for aggressive chemical serv-ice. XLPE is also commonly used as nuclear cable insulation, but suchapplications rarely involve aggressive chemical exposure. The pur-pose of this study was to determine the synergistic effects of tempera-ture, chemistry and radiation on the mechanical and structural prop-erties of a modified XLPE material. This study characterizes thechanges in mechanical properties by traditional tensile and hardnesstesting. Chemical structure changes and degradation products will bemonitored using spectroscopic techniques including FTIR and FT-Raman. Thermal stability will be evaluated using differential scan-ning calorimetry (DSC) and thermal gravimetric analysis (TGA)techniques.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 37

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania38

11:00 AMAdsorption and Separation of Uranium Using Tungsten OxidesA. Apblett*, H. Al Busaidi, Oklahoma State University, USA

Nuclear energy is attractive because it does not contribute to globalwarming. However,the production of nuclear energy has its own en-vironmental impacts. The mining and refining of uranium producestailings that leach uranium and other toxic metals into aquifers. Mili-tary use of depleted uranium also releases materials that also contam-inate water supplies. However, the more common route for humaningestion of uranium is from natural waters in contact with ura-nium-rich granitoids. There is a strong need for processes to preventcontamination of aquifers and purification of drinking water sup-plies due to uranium’s health risks. Tungsten trioxide and tungsticacid are effective for the removal of uranium from drinking waterwith high capacity and selectivity. An attractive feature of this processis the ease by which the uranium can be isolated and the sorbant canbe regenerated for reuse. It is also effective for other metals that are ofmore interest to the petrochemical and coal industry such as cad-mium and lead.

Environmental & Energy Issues: EnergyMaterials

BatteriesRoom: 327Session Chairs: Fatih Dogan, Missouri University of Science andTechnology; Masanobu Awano, National Institute of AdvancedIndustrial Science and Technology

10:20 AMStructural and electrochemical properties of chemical solutionderived Li(Mn0.475Cr0.05Ni0.475)O2 layered cathodes forrechargeable Li ion batteriesN. Karan*, D. Pradhan, J. Saavedra-Arias, A. Kumar, R. Thomas, R. Katiyar,University of Puerto Rico, USA

LiMn0.5Ni0.5O2 is a fascinating cathode for rechargeable Li-ion batteriessince all Mn ions are present as electrochemically inactive Mn+4 (d3 sys-tem),which gives structural stability and the only electrochemically activespecies present is Ni2+. In an attempt to increase the capacity by intro-ducing more electrochemically active species, the substitution of a frac-tion of the transition metal ion by Cr while maintaining Mn/Ni=1 is aninteresting option. In the present work, Li(Mn0.475Cr0.05Ni0.475)O2bulk cathode has been synthesized using a cost effective chemical solutiontechnique. A first cycle discharge capacity of 160 mAh/g was obtained inthe voltage range 2.5-4.5 V. Two redox couples are involved in the electro-chemical (de)lithiation process, namely, Ni+2/Ni+4 and Cr+3/Cr+6. Exsitu XRD, Raman and XPS measurements after electrochemical cyclingshowed that the structure remained intact during charge discharge.

10:40 AMAtomic-Scale Insight into the LiFePO4 Battery Material: Defects,Dopants and SurfacesM. Islam*, C. A. Fisher, University of Bath, United Kingdom

Future sustainable energy systems will include technologies based onenergy storage such as lithium ion batteries. LiFePO4 olivine-typecathode materials have been investigated as potential candidates foruse in hybrid electric vehicles. This follows the worldwide success ofrechargeable lithium batteries in portable electronics. Atomisticmodeling techniques combined with structural methods are beingused to probe the defect, dopant and lithium transport properties ofLiFePO4 based materials [1]. Recent work includes studies of the sur-faces and morphologies of oxide nanoparticles[2]. 1. Islam MS et al,Chem. Mater. 17, 5085 (2005) 2. Fisher CAJ and Islam MS, J. Mater.Chem. 18, 1209 (2008)

11:00 AMThermoelectric and mechanical properties of polycrystallinecopper aluminateC. Liu, F. Ren, D. Morelli, E. D. Case*, B. D. Hall, Michigan State University,USA; H. Wang, Oak Ridge National Laboratory, USA

Copper aluminate (CuAlO2) is a candidate for both photocatalyticgeneration of hydrogen and thermoelectric power generation ap-plications. Undoped as well as MgO-doped copper aluminate pow-ders (synthesized via solid state reaction) have been cold pressedand sintered. Mechanical property measurements of the polycrys-talline CuAlO2, including hardness, Young’s modulus, shear mod-ulus and Poisson’s ratio will be discussed along with calculationsof the acoustic Debye temperature. Samples containing MgO dis-play increased electrical conductivity and p-type behavior. Resultsof Seebeck and thermal conductivity measurements will also bepresented.

Environmental & Energy Issues: NanoscaleDesign of Materials for Extreme RadiationEnvironments

Fundamentals of Nanoscale Design for RadiationDamage Tolerance IRoom: 323Session Chair: Brian Wirth, University of California, Berkeley

9:40 AMCorrosion and Radiation Response of a 9Cr ODS Steel (Invited)T. Allen*, Y. Chen, K. Sridharan, U.Wisconsin, USA; J. Gan, Idaho NationalLaboratory, USA

Oxide dispersion strengthened steels have been developed to oper-ate at higher temperatures than traditional ferritic-martensiticsteels. Heavy-ion irradiation has been used to determine the oxidestability in a 9 Cr martensitic steel containing nanometer scale dis-persions of Y-Ti-O particles. The ODS steel was irradiated over 500-700°C to doses of 150 dpa. At all temperatures, the average oxidesize decreases but the oxide density increases. The changes in oxidesize are not entirely driven by ballistic processes but are stronglytemperature dependent. Corrosion response of ODS steels was ex-amined in supercritical water at temperatures of 500oC and 600oCat a pressure of 25 MPa. TEM investigation with EDS analysis re-vealed that yttrium preferentially segregated to oxide ribbons thatformed along the oxide/metal grain boundary regions in the inter-nal oxidation layer. The formation of these ribbons likely reducedthe cation flux at these regions, while not significantly affecting in-ward oxygen diffusion.

10:20 AMThe Mechanism of Irradiation Hardening Accompanied by No-loss-of-elongation in ODS steels (Invited)A. Kimura*, Kyoto University, Japan

Recent studies on irradiation effects on oxide dispersion strength-ening (ODS) steels indicated that they were hardened by neutronirradiations accompanied by no-loss-of-elongation. This is consid-ered to be an appropriate character of structural materials for ad-vanced nuclear systems where high burnup operation is de-manded. The reduction of elongation after the neutron irradiationhas been one of general features of metallic materials, which is in-terpreted in terms of channel deformation induced by localizeddislocation motion in the slip planes where irradiation-induceddamage structures are swept out by leading dislocations. In theODS steels, it is considered that the channel deformation can besuppressed by nano-sized dispersed oxide particles because theleading dislocations are pinned by the particles and the following

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 38

Mo

nd

ay A

M

www.matscitech.org 39

dislocations are piled up at the particle, which results in the sup-pression of the dislocation source and the activation of the otherdislocation sources.

11:00 AMStructure and composition of Y-Ti-O nanoclusters innanostructured ferritic alloys (Invited)B. D. Wirth*, University of California, Berkeley, USA; G. Odette, University ofCalifornia, Santa Barbara, USA

Advanced fission and future fusion energy will require new high-per-formance structural alloys with outstanding properties that are sus-tained under long-term service in extreme environments. Following abrief description of irradiation damage and the criteria required fordamage resistance, the presentation will focus on an emerging class ofnanostructured ferritic alloys (NFAs) that show promise for meetingthese challenges. NFAs contain an ultrahigh density of Y-Ti-O-en-riched dispersion-strengthening nanofeatures (NFs) that, along withfine grains and high dislocation densities, provide remarkably hightensile, creep, and fatigue strength, and appear remarkably radiationtolerant. Semi-empirical interaction potentials, fit to electronic struc-ture calculations have been used to investigate the atomic-scale struc-ture and composition of the NFs. The modeling results are comparedto available experimental data, and provide insight into the propertiesand performance of the NFAs.

Fundamentals & Characterization: CeramicSurfaces, Grain Boundaries and Interfaces

Interface Thermodynamics andSegregation/Adsorption IRoom: 301Session Chairs: Dominique Chatain, CNRS; Wayne Kaplan,Technion

9:40 AMHigh-Temperature Spreading (Invited)E. Saiz*, A. P. Tomsia, Lawrence Berkeley National Laboratory, USA

In this talk the high temperature spreading of molten metals and ox-ides is evaluated mechanistically. The analysis combines experimentsperformed in systems with different degrees of reactivity using drop-transfer and capillary rise set-ups. Theories for the energetics and ki-netics of the steps involved in spreading are outlined and comparedto the steps in the compound formation that typically accompaniesreactive wetting. These include: fluid flow, active metal adsorption,including nonequilibrium effects, and triple line ridging. They can allbe faster than compound nucleation under certain conditions. Thisanalysis leads to a focus on those a condition under which spreadingproceeds ahead of the actual formation of a new phase. This scenariomay be more typical than commonly believed. A rationale for theslow spreading rates plus the pervasive variability and hysteresis ob-served during high temperature wetting also emerges.

10:20 AMAnisotropy of Interfacial Segregation (Invited)P. Wynblatt*, Carnegie Mellon University, USA

Models have recently been developed for calculating segregation ef-fects (i.e. the variation of composition) in the vicinity of varioustypes of interfaces, including surfaces, grain boundaries and inter-phase boundaries, as a function of interface orientation. At this time,the approach is only suitable for addressing such phenomena inmetallic alloy systems. The models have also been extended to a num-ber of related phenomena, such as wetting at interfaces and the equi-librium shape of alloy crystals. An overview of recent results will beprovided.

11:00 AMAdvanced S/TEM for atomic-scale characterisation and analysis ofinterfaces and grain boundaries (Invited)B. Freitag*, D. J. Stokes, FEI Company, Netherlands; J. Ringnalda, FEICompany, USA; D. H. Hubert, FEI Company, Netherlands

The need for tools that can deliver ultra-high resolution informationis driving the development of electron microscopy and spectroscopyto the extremes of performance. We have been developing aberration-corrected and monochromated (scanning) transmission electron mi-croscopy (S/TEM) that eliminates delocalisation effects and gives usthe ability to work at sub-angstrom length-scales, coupled withsharply-defined energy resolution for spectroscopic techniques. Thisenables us to acquire information at the single atomic level and gainknowledge of inter-atomic bonding for precise characterisation ofchemical composition and electronic structure. We are able to usethese new capabilities to great effect in the study of interfaces andgrain boundaries, giving new insights.

11:20 AM3D Atomic-scale Measurements of Surface and InterfaceChemistry in Metallic Systems (Invited)A. Cerezo*, P. A. Bagot, E. A. Marquis, A. Morley, D. W. Saxey, G. Sha, C.Williams, G. D. Smith, University of Oxford, United Kingdom

The 3-dimensional atom probe (3DAP) permits 3D reconstruction ofatomic-scale chemical variations in conductive materials, termedatom probe tomography (APT). Position-sensitive time-of-flightmass spectrometry is used to locate (to sub-nanometre resolution)and chemically identify single atoms removed from the surface of aneedle-shaped specimen (end radius 50 - 100 nm). APT can provideunique 3D data on segregation to the interfaces of nanoscale second-phase precipitates, whose curvature all but precludes the use of trans-mission electron microscopy techniques that view the specimen inprojection. This paper will present results on metal/metal andmetal/oxide interfaces in engineering materials of interest for powergeneration. The specimen shape in APT is also a good model for ananoscale catalyst particle, on which many crystallographic planes areexposed, and has allowed investigation of the surface chemistry of Pt-Rh alloy (automobile exhaust catalyst) after exposure to nitric oxide.

Fundamentals & Characterization: Discoveryand Optimization of Materials throughComputational Design

Thermodynamic and Kinetic Processes for MaterialsOptimization IRoom: 303Session Chairs: Anton Van der Ven, University of Michigan; MarkAsta, University of California at Davis

9:40 AMApplications of First-Principles Thermodynamics and Kinetics inthe Context of Materials Optimization (Invited)M. Asta*, University of California at Davis, USA

Computer-aided optimization of alloy properties often requiresdetailed knowledge of the thermodynamic and kinetic propertiesunderlying the evolution and stability of microstructure. First-principles methods are receiving growing attention as a frameworkfor calculating these properties in cases where data is difficult toextract directly from experimental measurements. This talk willdescribe some recent developments realized in this context, em-phasizing comparison with experimental data to assess the accu-racy of the computational methods. We consider in particular cal-culations of impurity diffusion coefficients in both solid andliquid alloys, and thermodynamic and kinetic properties of liquid

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 39

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania40

alloys. We review the methods for performing such calculationsemploying the framework of density functional theory, harmonictheory, and molecular dynamics. Results will be discussed in thecontext of materials optimization problems in Ferritic and Ni-based alloys.

10:20 AMDesign and Implementation of a Repository for InteratomicPotentialsC. A. Becker*, National Institute of Standards and Technology, USA

With the increasing demand and use of atomistic simulation tech-niques in materials research and design, the need for a repositoryof interatomic potentials and the means to compare them be-comes ever more important. This is especially true given thesometimes widely different properties calculated using inter-atomic potentials that are nominally the same element or alloy.Here we will focus on the development of a public repository atthe National Institute of Standards and Technology to provide asource for vetted interatomic potentials, as well as reference exper-imental and ab-initio data for comparison. The development ofstandard evaluation methods (including thermodynamic, kinetic,and mechanical properties) and distribution methods will also bediscussed.

11:00 AMTowards an Error-Controlled Multi-Scale Materials Modeling(Invited)K. Reuter*, Fritz-Haber-Institut der MPG, Germany

Computational modeling is becoming a key contributor in modernmaterials science, pushing novel hierarchical approaches that inte-grate various levels of theory into one multi-scale simulation andspan disparate regions in length and time. Critical to assigning thedesired predictive quality to such simulations are robust links be-tween the theories with error-control across the scales. At each scale,simulations have approximations that introduce uncertainty, andbridging from one scale to another gives rise to additional un¬cer-tainty. Only a stringent control of how these multiple sources of un-certainty affect the final multi-scale re¬sults allows to propagate aninitial base accuracy up the increasing length and time scales. Usingexamples from heterogeneous catalysis, I will sketch our efforts to-wards such an error-controlled multi-scale modeling using density-functional theory (DFT), kinetic Monte Carlo and rate equation the-ory to treat the electronic, statistical and continuum levels,respectively.

11:40 AMThe apparent paradox of the Gibbs-Thompson phenomenon is thethermodynamic limit for the growth of single walled carbonnanotubes from Fe and Fe:Mo catalysts (Invited)S. Curtarolo*, W. Setyawan, Duke University, USA; K. Bolton, GöteborgUniversity, Sweden; A. Harutyunyan, Honda Research Institute , USA

Fe and Fe:Mo nanoclusters are becoming the standard catalysts forgrowing single-walled carbon nanotubes (SWCNTs) via chemicalvapor decomposition (CVD). Contrary to the Gibbs-Thomson for-malism, we show experimentally that reducing the size of the catalystbeyond a certain limit requires increasing the (minimum) growthtemperature. We resolve this apparent paradox in terms of solubilityof C in Fe nanoclusters and, by using first principles calculations, weconstruct a thermodynamic model to determine the behavior of thephases competing for stability. We show that, as a function of particlesize, there are three scenarios: steady state-, limited-, or no-growth ofSWCNTs, corresponding to unaffected, reduced, and zero solubilityof C in the clusters. The results are extended to Fe-Mo binary catalystsin which we answer the 15+ year long-standing question about the ef-fects of Mo concentrations on the growth capability.

Fundamentals & Characterization: FailureAnalysis for Problem Solving

Joining, Welding and BrazingRoom: 304Session Chairs: Erhan Ulvan, ACUREN Group Inc.; Ron Parrington,IMR Test Labs Inc.

9:40 AMAre Standard Specifications for Weld Quality Enough? (Invited)D. McGarry*, SEA Ltd, USA

Numerous standards apply to welded components and fabricatedparts. This presentation will address a specific ASTM standard forelectrical resistance welded (ERW) tube, ASTM B 500 “StandardSpecification for Cold-Formed Welded and Seamless Carbon SteelStructural Tubing in Rounds and Shapes”. The presentation will re-view an incident in which weld deficiency was reported to cause thecollapse of a newly constructed automated storage rack structure(ASRS). The property loss was claimed to be $68 million in additionto loss of life. The strength and limitations of this particular ASTMstandard will be reviewed in the context of the failure.

10:20 AMCorrosion-Fatigue of Friction Stir Welded Lap Joints with SealantsK. T. Doering*, D. C. Van Aken, Missouri University of Science andTechnology, USA; R. J. Lederich, Boeing - Phantom Works, USA

Corrosion-fatigue studies were conducted on T-joint assemblies pro-duced with 2024-T8 top-skins friction stir-welded to A357-T6stringers. Aluminum components were sulfuric acid anodized and asealant was used to fill the faying surfaces of the lap joint assembly.Various sealants were compared including a fluorosilicone rubber ora thermoplastic such as nylon-11 or polyetheretherketone. Corro-sion-fatigue studies were performed by immersing the lap joint inneutral salt water and cycling with R=0.1 until failure and were com-pared with equivalent testing results in air. Finite element modelingwas used to predict stress intensity factors and crack propagation. Im-mersion in the saline solution reduced failure lives by 75% even whena lap joint sealant was used. Hydrogen transport through the weldnugget and subsequent hydrogen charging may have accelerated thecrack growth rate. These results suggest that the weld scroll surfacemust be protected to prevent active corrosion and hydrogen charging.

11:00 AMAnalysis of Weld Related Pipeline FailuresG. T. Quickel*, B. C. Rollins, J. A. Beavers, CC Technologies, Inc. (a DNVcompany), USA

There are more than 2.5 million miles of oil and gas pipelines in theUnited States. These pipelines typically contain longitudinal seamwelds in each pipe joint and girth welds that connect the individualjoints to form the pipeline. Both types of welds are prone to failurefrom time independent and/or time dependent failure mechanisms.This paper reviews common pipeline welding types and provides sev-eral case histories in which failure analysis techniques were used todetermine a metallurgical cause of failure.

11:20 AMFour Red Herrings, Float Switch Failure and a Case of MultipleFailure ScenariosP. H. DeVries*, The Boeing Company, USA

In the course of a failure investigation, the Analyst may be faced withmultiple failure scenarios including those promoted by the manufac-turer, suggested by the customer, uncovered by the investigation, orassumed by the analyst. This case study covers investigation of fuelfloat switches in which evidence was found to support several pro-posed, but ultimately misleading, failure scenarios. The true root

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 40

Mo

nd

ay A

M

www.matscitech.org 41

cause, solder creep, was determined only after a reexamination of pre-liminary failure mode assumptions. Proper root cause diagnosis un-derscored the danger of assumptions and the value of both expertknowledge and broad based experience in failure analysis to ensure aproper conclusion.

11:40 AMWeldment Cracking of Center Baffle Wall Plate Attachments toTurbine End of a Power PlantS. Nasrazadani*, University of North Texas, USA; D. Hopkins, SouthwestResearch Institute, USA

Failed welded low carbon steel plate and a baffle wall that werewelded to a tubular support member located at the end of the turbinestage of a power plant were investigated. Identification of chemicalcomposition, mechanical properties evaluation, and morphologicalanalysis utilizing a scanning electron microscope for fracture mecha-nism investigation were performed. Results of the fracture surfacesanalysis showed evidence of cracks propagating in response to cyclicloading at varying stress intensity. In addition, the weldment was notfully fused but a segment of this weld apparently was strongly at-tached to the tubular member. This weld segment appeared to havefailed in a brittle manner, either by fatigue or by a high-strain-rateevent. The root cause for the observed cracking was the action of res-onant vibratory forces acting on an under-strength design low carbonsteel plate. A number of possible corrective actions are proposed.

Fundamentals & Characterization: Fatigue ofMaterials: Competing Failure Modes andVariability in Fatigue Life

Crack Initiations and Variability IRoom: 305Session Chairs: G. Cashman, University of Utah; K. Ravi Chandran,University of Utah

10:00 AMStatistical Duplex S-N Characteristics of High Carbon ChromiumBearing Steel in Rotating Bending in Very High Cycle Regime(Invited)T. Sakai*, Ritsumeikan University, Japan; M. Takeda, Toray Industries Inc.,Japan; K. Shiozawa, University of Toyama, Japan; Y. Ochi, University ofElectro-Communications, Tokyo, Japan; M. Nakajima, Toyota College ofTechnology, Japan; T. Nakamura, Hokkaido University, Japan; N. Oguma,University of Toyama, Japan

In order to clarify the statistical S-N property in very high cycleregime, gigacycle fatigue tests were carried out on SUJ2 steel in rotat-ing bending. Thus the complicated S-N characteristics of this steelwas interpreted as duplex S-N curves for the respective fracturemodes of surface-induced fracture and the interior inclusion-in-duced fracture with a fish-eye. By applying mixed-mode Weibull dis-tribution, such a statistical aspect was well analyzed quantitatively.

11:00 AMDuality in Fatigue Variability in Probabilistic Life-Prediction ofTurbine Engine Materials (Invited)S. K. Jha*, Universal Technology Corporation, USA; M. J. Caton, J. M. Larsen,US Air Force Research Laboratory, USA

Physics-based probabilistic methods are essential in appreciably re-ducing the uncertainty in fatigue life prediction. Towards this objec-tive, the role of competing mechanisms in producing dual-fatiguevariability behavior in turbine engine materials is discussed. Thecompeting modes were related to randomly occurring microstruc-tural configurations, differing in the degree of heterogeneous defor-mation accumulation in fatigue. The fatigue variability was describedas a sequence of mechanisms, probabilistically originating from these

configurations, in the order of decreasing heterogeneity level. Thesemechanisms grouped into two primary contributions to the lifetimeprobability density: (i) the mean-lifetime response and (ii) the crack-growth-controlled, life-limiting behavior. A model accounting forthis dual behavior was developed and provided reasonable predic-tions of the influence of material and extrinsic variables on the life-time density and the probabilistic lifetime-limit.

11:40 AMFatigue Life Variability Due to Crack Initiation at Soft Grains andHard Particles (Invited)K. S. Chan*, Southwest Research Institute, USA

Soft surface grains and hard interior particles are favored sites for fa-tigue crack initiation, whose subsequent growth can lead to compo-nent failure. In this paper, we examine the competing processes ofcrack initiation at hard alpha particles and soft primary alpha grainsin two-phase Ti alloys. Microstructure-based fatigue models are uti-lized to treat fatigue crack initiation and growth separately and to de-lineate the effects of microstructure on fatigue life variability. Specifi-cally, we focus on the manner by which competing fatigue crackinitiation processes affect the shape of the stress-fatigue life (S-Nf)curves. For example, soft primary alpha grains in Ti-alloys with a du-plex microstructure concentrate both plastic strain and hydrostaticstress and lead to bilinear S-Nf curves that deviate substantially fromthe Goodman relation. In contrast, crack initiation at small hard par-ticles can lead to the occurrence of a lower fatigue limit in the ultra-high cycle fatigue regime.

Fundamentals & Characterization:International Symposium on Defects,Transport and Related Phenomena

Defects and Transport Related to Fuel Cells andBatteries IRoom: 307Session Chair: Alastair Cormack, Alfred University

9:40 AMAtomic-Scale Studies of Complex Oxide Materials for Fuel Cellsand Lithium Batteries (Invited)M. Islam*, University of Bath, United Kingdom

Fundamental materials research is a crucial component in the discov-ery and optimisation of novel materials for energy applications suchas fuel cells and lithium batteries. In addition, advanced computa-tional techniques are now powerful tools for probing the propertiesof materials on the atomic and nano-scale. This presentation willhighlight recent studies focusing on two principal themes: (i) fast-ionconductors for solid oxide fuel cells (e.g. LaBaGaO4 gallium-ox-ides[1] and La-apatites[2]), and (ii) electrode materials for lithiumbatteries (e.g. LiFePO4 [3]) for potential use in hybrid electric vehi-cles. The key properties that are investigated include defects, dopantsand ion transport mechanisms, which are correlated with the avail-able structural and conductivity data. 1. Kendrick E et al., NatureMater. 6, 871 (2007). 2. Tolchard J R et al., Adv. Funct. Mater. 17, 2564(2007). 3. Fisher C A J and Islam M S, J. Mater. Chem. 18, 1209 (2008).

10:20 AMElectrical Current Effect on Microstructural Changes in 8YSZS. Kim*, S. L. Kang, Korea Advanced Institute of Science and Technology,South Korea; S. Kim, I. Chen, University of Pennsylvania, USA

The effect of a high current density on the grain-boundary migrationin fully dense and 95% dense 8 mol% Y2O3 stabilized ZrO2 ceramics(8YSZ) has been investigated. Grain growth and densification werepromoted in the negatively biased region rich in positively chargedoxygen vacancies and the zirconium ions. However, in the positively

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 41

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania42

biased region, grain growth was inhibited and some new poresformed due to gaseous oxygen release. The size of grains increased by25 fold in samples loaded at 50A/cm2, after 1440min at approximately1000°C. There is usually a clear demarcation separating regions withand without changes in grain size and porosity. These experimentalobservations will be interpreted in terms of defect concentration andmobility that are influenced by an electric field.

11:00 AMGrain Core vs. Grain Boundary Electrical Properties in Undopedand Doped CeriaT. C. Yeh*, N. H. Perry, T. O. Mason, Northwestern University, USA

Nano-ionics show promise for more efficient and reliable low tempera-ture energy conversion technologies, e.g., as electrolytes and electrodes insolid oxide fuel cells. The recently developed nano-Grain CompositeModel (n-GCM) enables reliable extraction of local grain boundary vs.grain core electrical/dielectric properties at the nanoscale. The n-GCMwas applied to undoped and gadolinia-doped cerium oxide. The resultswere analyzed in terms of grain core vs. grain boundary properties (con-ductivity, dielectric constant) and grain boundary width, which shouldcorrespond to twice the space charge width in each material. Compar-isons were made with literature values acquired by the conventional BrickLayer Model approach. Results will be discussed in terms of space chargeand impurity segregation effects. Ramifications for the use of nano-ion-ics in intermediate-temperature SOFCs will be discussed.The general ap-plicability and limitations of the n-GCM will also be presented.

11:20 AMDevelopment of a Defect Model for LiFePO4 (Invited)R. Amin, K. Weichert*, J. Maier, Max Planck Institute for Solid State Research,Germany

LiFePO4 is a promising material for lithium batteries. Understandingthe defect chemistry is the prerequisite of systematically designingmaterials that overcome the problem of insufficient transport prop-erties. For this purpose conductivity measurements both on polycrys-talline material and single crystals of pure and doped LiFePO4 wereperformed. Holes and lithium vacancies are found to be the decisivecharge carriers in LiFePO4. Accordingly, Li loss increases not only theelectronic but also ionic conductivity; by donor doping the concen-tration of lithium vacancies is increased, leading to higher ionic con-ductivity compared to pure LiFePO4 while the electronic transport isdepressed. Based on the experimental results a quantitative defectmodel for LiFePO4 was developed that takes also account of defect as-sociation. The dependence of the defect concentration as a functionof temperature, lithium activity, and doping content were elaboratedand is given in terms of Brouwer diagrams and activation energies.

Fundamentals & Characterization: Modelingof Multi-Scale Phenomena in MaterialsProcessing

Stress AnalysisRoom: 306Session Chairs: Fang Cao, Los Alamos National Lab; AdrianCatalina, Caterpillar Inc.

9:40 AMImpact of boron isotope on the thermal properties of ZrB2 – SiCceramicsM. P. Teague, J. L. Watts*, G. E. Hilmas, W. G. Fahrenholtz, MissouriUniversity of Science & Technology, USA

ZrB2–SiC ceramics were reaction hot pressed from zirconium hydrideand elemental boron along with the addition of 30 vol% silicon car-bide. Both naturally occurring boron (containing both 10B and 11Bisotopes) and isotopically pure 11B were used to evaluate the effect of

boron isotope on the thermal properties of the ceramics. Thermal dif-fusivity was measured and used, along with density and heat capacitymeasurements, to calculate the thermal conductivity of each material.Neutron diffraction experiments were used to determine the bulkresidual stresses for bars of Zr11B2-SiC, Zr11B2, and SiC. Referencestress free powder samples of Zr11B2 and SiC were measured usinghigh temperature X-ray diffraction. Measured residual stresses werecompared to stresses predicted using a finite element model. Thermalexpansion, based on the lattice parameters, was also determined forpowder samples and rectangular bars made from ZrB2 and SiC.

10:00 AMEffect of Crystal Orientation on Stress Distribution Near theTriple Junction in a Tricrystal Gamma-TiAl Finite ElementAnalysisA. Fallahi*, A. Ataee, F. Biglari, Amirkabir University of Technology, Iran

The mechanical properties of intermetallic Gamma-TiAl based mate-rials depend strongly on the microstructure. The crystallographic fi-nite element results show that the stress distribution near the grainboundary and triple junctions is very complex. This stress concentra-tion depends on grain orientation and its stiffness matrix of neigh-boring grains. Grain boundary analysis should be established on thebasis of crystallographic constitutive theory and finite deformation. Athree-dimensional anisotropic finite element analysis is performingto investigate stresses in the models that were taken from a Gamma-TiAl tricrystal. The purpose of this paper is to determine how crystalorientation affects the stress-state near the triple junction. Stresses atsurfaces are significantly different from the interior stresses neartriple junction. Stresses can vary by 45% and near grain boundariescan be 20% to 30% larger than the average stress in the material.

Microstructure Evolution IRoom: 306Session Chair: Anthony Rollett, Carnegie Mellon University

11:00 AMOrigin of the Nano-Chessboard Structures: From Tweed to Two-phase Chessboard Architecture (Invited)Y. Ni*, A. Khachaturyan, Rutgers University, USA

A 3-dimensional nano-chessboard (CB) structure is one of the mostintriguing structural architectures observed in decomposing metaland ceramic systems. To understand the physical origin of the CBstructure, we employed the 3D Phase Field Microelasticity modelingof the cubic to tetragonal decomposition, which takes into accountthe chemical, elastic and interfacial energies to the driving forces of amicrostructure spontaneously evolving from the initial homoge-neous to two-phase states without a priori assumptions about thetransformation path. Our modeling demonstrated that the CB struc-ture forms only from an initially developed precursor tweed structurewith CB geometrical features. This tweed structure serves as a tem-plate channeling the microstructure evolution towards the two-phaseCB structure. The obtained CB structure is in excellent agreementwith the experiments. Special thermodynamic, crystallographic andkinetic conditions result in the precursor state are established.

11:20 AMModeling Dynamic Extrusion of Tantalum: Influence of Textureand Extrusion VelocityE. Cerreta*, F. Cao, G. T. Gray III, C. P. Trujillo, M. Burkett, Los AlamosNational Lab, USA

The mechanical behavior and damage evolution response of high-purity Ta are known to be influenced by strain rate, temperature,stress state, grain size, and texture. Additionally, the effects of textureon the mechanical response of high-purity Ta have been probed andare correlated with the substructural evolution during deformation.In the current work, the dynamic extrusion response of Ta demon-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 42

Mo

nd

ay A

M

www.matscitech.org 43

strates the influence of texture on the large-strain dynamic tensileductility. Eulerian hydrocode simulations utilizing the MechanicalThreshold Stress flow stress model were performed to provide insightinto the dynamic extrusion process. Quantitative comparisons be-tween the predicted and measured deformation topologies and extru-sion rate will be presented. Predictions of the texture evolution(based upon the deformation rate history and the rigid body rota-tions experienced by the Cu during the extrusion process) are com-pared with post mortem texture measurements.

11:40 AMSubgrain Structural Evolution in Hot-rolled AA5005 Aluminum AlloyS. Wang*, A. D. Rollett, Carnegie Mellon University, USA

Hot rolled aluminum alloy AA 5005 has been characterized using Elec-tron Backscatter Diffraction. Based on the EBSD scans of 2 orthogonalobservation sections, 3D digital subgrain structures are built up using the3D Microstructure Builder, a computational tool for developing statisti-cal representations of microstructures, to incorporate both texture andsubgrain shape information. Monte Carlo simulations were performedsubsequently on these digital structures. The anisotropy of grain bound-ary properties, texture sharpness (represented as grain orientation devia-tion), and interface between two textures are examined to evaluate theirimportance for promoting abnormal (sub-) grain growth. Results showthat anisotropy of grain boundary properties is most important, followedby texture sharpness and interface. The aim of this parametric analysis isto help us to understand circumstances under which we can expect ab-normal (sub-)grain growth leading to nucleation of recrystallization.

Fundamentals & Characterization: PhaseStability, Diffusion Kinetics and TheirApplications (PSDK-III)

Microstructural Analysis, Control and Modeling IRoom: 302Session Chairs: John Morral, The Ohio State University; YonghoSohn, University of Central Florida

9:40 AMDynamic 3D Microstructures by Design (Invited)G. B. Olson*, Northwestern University, USA

While modeling of high-supersaturation precipitation phase trajec-tories as unstable equilibria allows separation of space and time forefficient parametric design of new alloys, process optimization at thecomponent level and the forecasting of variation in manufacturingemploying the DARPA-AIM acceleration methodology demands di-rect simulation of precipitation transients in nonisothermal process-ing. In support of higher accuracy in predictive process optimizationof advanced aeroturbine disc alloys, an ongoing NASA-supportedcollaboration addresses accuracy of commercial thermodynamic andmobility databases and the efficient calibration and validation ofnonisothermal precipitation simulation via the PrecipiCalc code de-veloped to support the AIM methodology. Higher fidelity predictionof spatial distributions of precipitates is being developed under theongoing ONR/DARPA “D3D” Dynamic 3D Structure consortium, in-tegrating a suite of multiscale tomographic characterization methodswith a new generation of 3D microstructural simulators.

10:20 AMMicrostructure-Based Modeling of Controlled Drug ReleaseCoatingsD. Saylor*, C. Kim, D. Patwardhan, U.S. Food and Drug Administration,USA; J. Warren, National Institute of Standards and Technology, USA

In recent years, controlled drug release coatings, comprising drug in apolymer matrix, have been integrated with medical devices to im-prove functionality and performance. While it has been demon-

strated that the internal structure of these composites significantly al-ters drug release, the impact of materials selection and manufactur-ing conditions on microstructure development during processingand the subsequent release kinetics is not well established. Therefore,we have developed a phase field model for microstructure evolutionin these coatings. Calculations based on the model are used to predictmicrostructural changes during both manufacturing and use. Thesecomputations, which are consistent with experimental observations,have been used to establish relations between processing, microstruc-ture, and drug release kinetics. These relations provide a means torapidly assess new products and processing routes, evaluate the suit-ability of process specifications, and guide product design.

11:00 AMKinetics of first-order phase transformations as studied by atom-probe tomography and simulations (Invited)D. N. Seidman*, C. Booth-Morrison, Y. Zhou, Northwestern University, USA

The temporal evolution of first-order phase transformations arestudied in model nickel-based superalloys employing atom-probe to-mography (APT), TEM, and SEM, and atomic scale simulations (lat-tice kinetic Monte Carlo) to understand the atomic mechanisms bywhich they occur. The effects of supersaturation on the kinetic path-ways in two Ni-Al-Cr alloys are presented and analyzed. The nucle-ation of the gamma prime (L12 structure) phase is studied by APTfor a Ni-Al-Cr alloy whose composition is close to the gamma primeplus gamma (fcc)/gamma solvus line. The effects of tantalum on thetemporal evolution of Ni-Al-Cr are also presented. First-principlessimulations, in combination with APT, are used to determine the sitepreference of the tantalum atoms in the L12 structure of the gammaprime phase. Research supported by the NSF-DMR.

11:40 AMOn the Existence of Our Metals-Based CivilizationD. D. Macdonald*, Penn State University, USA

Our metals based civilization is, by-and-large, built upon the reactivemetals (Al, Fe, Ni, Cr, etc), which are used to build machines that oper-ate in contact with a highly corrosive, terrestrial environment. This isonly possible, because of the phenomenon of passivity, in which a sur-face oxide film confers kinetic stability upon the substrate metal. How-ever, passive films are not perfectly protective and their general or local-ized breakdown can lead to corrosion rates in specific environmentsthat render reactive metals impractical as materials of fabrication. Thispaper explores the stability of the passive state and develops a mathe-matical criterion that indicates whether passivity can actually occur.This formalism has led to the development of Kinetic Stability Dia-grams, which the author proposes as alternatives for the classical equi-librium Pourbaix diagrams for assessing the stability of the passive state.

Fundamentals & Characterization: RecentAdvances in Structural Characterization ofMaterials

X-Ray and Neutron Diffraction: Developments andApplications IRoom: 309Session Chairs: Roumiana Petrova, New Jersey Institute ofTechnology; Jacob Jones, University of Florida

9:40 AMHigh temperature atmosphere controlled X-ray diffraction(Invited)S. Misture*, Alfred University, USA

High temperature powder X-ray diffraction is in the midst of a ren-aissance enabled by new X-ray optics, detectors, computational meth-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 43

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania44

ods, and furnace designs. In-situ diffraction, under controlled tem-perature, atmosphere, electric and magnetic field, etc. has proven in-valuable in many materials systems and is the often the only means ofexploring dynamics. The capabilities of new lab-based XRD systemswill be demonstrated using examples centered on ionic and electronicconductors that are sensitive to oxygen partial pressure. In addition,the talk will highlight current work on in-situ reduction and othercomplex gas-solid and solid-solid reactions that can be tracked usingtime intervals as short as a few seconds. Finally, the ability to identifyand solve new crystal structures from in-situ data will be discussedfor those materials systems that are not amenable to quenching. Re-cent success with ab-initio approaches to solving crystal structureswill demonstrate the value of new computational approaches.

10:00 AMHigh-temperature processing of microwave dielectric ceramics: insitu studies using neutron and synchrotron X-ray powderdiffractionR. M. Ibberson*, Rutherford Appleton Laboratory, United Kingdom; M. J.Rosseinsky, University of Liverpool, United Kingdom

State-of-the-art diffraction methods have been applied to study andunderstand the atomic-level processes and critical features of cationordering and domain growth in commercial electroceramics in situunder processing-like conditions. High-temperature processing iscrucial to the performance of these oxide materials in applicationsand we have developed high-resolution neutron and synchrotron X-ray powder diffraction methods to enable the key changes in theatomic scale structure to be followed at processing temperatures ofup to 1500 °C and on a time scale of seconds. Studies on theBa3ZnTa2O9 (BZT) and Ba3CoNb2O9 (BCN) families of materials willbe presented where the methodology was used to determine cationordering/disordering kinetics and in the identification of differentmechanisms for ordered domain growth in these materials associatedwith the formation of impurity phases.

10:20 AMSmall-Angle X-ray Scattering Analysis of Nanoparticles andNanofilms Using a General Purpose DiffractometerJ. Li*, A. Tripathi, L. Fields, A. Beitelman, T. McNulty, Rigaku AmericasCorp., USA

Characterization of nanomaterials, including their characteristicsizes and size distributions, has becoming increasingly important be-cause many of the properties of nanomaterials are dependent on thesize and uniformity of the nano features. Typically, microscopicmethods provide direct visualization of the nano-materials, but itoften requires sample preparation that may change their natural set-tings. Small-angle x-ray scattering (SAXS) is an indirect method thatcan provide the same information without change the sample set-tings. However, a SAXS experiment usually requires specializedequipment that can be costly. Here we present examples of perform-ing SAXS analysis using an improved general purpose diffractometer.We show that other measurements, such as XRD and x-ray reflectiv-ity, can be easily integrated to obtain a better understanding of thenano-materials.

11:00 AMNegative Thermal Expansion Materials under Pressure (Invited)A. P. Wilkinson*, Georgia Institute of Technology, USA

Negative thermal expansion (NTE) materials are of interest for con-trolled expansion composites. However, they are typically low in den-sity with flexible framework structures leading to rich behavior undermodest pressures. Crystalline to crystalline phase transitions, involv-ing a loss of NTE, and pressure induced amorphization are common.In some cases the processing or heating of composites can lead tophase transitions. Thermal expansion coefficients for NTE materialscan sometimes be changed significantly on modest loading withoutany phase transitions. The high pressure behavior of NTE materials

will be illustrated with: 1) studies of crystalline to crystalline transi-tions in Sc2W3O12 materials in diamond anvil cells, 2) combined ab-sorption and diffraction measurements examining the pressure in-duced amorphization of ZrW2O8, 3) neutron studies of pressureinduced changes in the thermal expansion coefficient of TaO2F, and4) high temperature/pressure diffraction studies examining the sta-bility of ZrV2O7.

11:20 AMMulti-component gradient microstructure characterization byanomalous ultrasmall-angle X-ray scattering (Invited)A. J. Allen*, NIST, USA

Materials for nanotechnology or energy independence can containstructure over a scale range from nanometers to micrometers, multi-ple microstructure components, spatial gradients, and/or stronganisotropy. All these aspects must be characterized to establish theprocessing–microstructure–property relationships that govern per-formance. Development of ultrasmall-angle X-ray scattering(USAXS) methods has provided statistically-representative mi-crostructure information over the scale range required and small X-ray beams allow microstructure gradients to be interrogated. USAXSmeasurements, made at each sample position using several X-ray en-ergies just below the X-ray absorption edge for a selected atomicspecies in the system, can distinguish between microstructural com-ponents. For a truly multi-component system correlated anomalousUSAXS measurements are needed at two or more widely separatedabsorption edges. Such studies of a solid oxide fuel cell system will bediscussed.

11:40 AMSingle Crystal X-ray Diffraction in the Transmission Mode forFerroelectric MaterialsA. Sehirlioglu*, D. Payne, P. Han, S. Wilson, NASA Glenn Research Center, USA

X-ray diffraction in the transmission mode has long been used instructure determination of organic crystals and proteins; however, itis not used much to characterize inorganic systems.0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 single crystals were examined bythis XRD technique for the first time, and a never-before-seen super-lattice was revealed with a doubling of the unit cell in all three direc-tions, giving a cell volume eight times that of a traditional perovskiteunit cell. Non-destructive sample preparation made it possible to col-lect forward diffracted x-rays at different poling states of the crystal.The significance of the super-lattice peaks increased with poling, in-dicating a structural contribution to ordering. Lack of such observa-tions by electron diffraction in the transmission electron microscopeexaminations suggests the presence of a bulk effect.

Iron & Steel: New Developments inProcessing and Properties of Zinc-CoatedSheet Steels

New Developments in Processing and Properties ofZinc-Coated Sheet Steels IRoom: 328Session Chair: Frank Goodwin, ILZRO

9:40 AMControlling Surface Oxidation Prior to Coating High StrengthSheet SteelsG. M. Michal*, Case Western Reserve University, USA; Y. Jin, D. Paik, POSCO,South Korea

The higher alloy content of Advanced High-Strength Steel (AHSS)can lead to the formation of oxide phases on its surface during con-tinuous annealing cycles. These oxide phases can generate poor wet-ting conditions during the hot-dip galvanizing (HDG) coating

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 44

Mo

nd

ay A

M

www.matscitech.org 45

process. The effects of annealing temperature and atmosphere on thedriving force for either external, or internal, oxidation have been eval-uated using CALPHAD-based solution thermodynamic data. Mapswere constructed that define what oxidation reactions will occur as afunction of alloying element concentration in the steel and the partialpressure of oxygen in the annealing atmosphere. The extension ofsuch oxidation maps to account for oxidation reactions along grainboundaries will be discussed.

10:00 AMEffect of TRIP Steel Surface Chemistry on Reactive Wetting duringHot Dip GalvanizingE. M. Bellhouse*, J. R. McDermid, McMaster University, Canada

Galvanizing of transformation induced plasticity (TRIP)-assistedsteels can be challenging due to the selective oxidation of the alloyingelements Mn, Si and Al. Improvements in the galvanizability of TRIP-assisted steels have been made by changing the oxidation potential ofthe process atmosphere used during annealing prior to galvanizing.The effect of process atmosphere, intercritical annealing temperatureand bainite hold time on the development of the surface structureprior to galvanizing and on reactive wetting during galvanizing of a1% Si – 0.5 % Al TRIP steel will be discussed.

10:20 AMOxidation Behavior of TRIP Steels Containing Si, Mn, BS. Lee*, R. Park, Y. Choi, POSCO Technical Research Laboratories, South Korea

It is well known that selective oxidation of Si, Mn, B on the surface ofTRIP steels during the heat treatment. However, it is not clear that therelationship between the oxide formation and manufacturing factorssuch as cooling temperature, cooling rate, etc. In this study, oxidestructrure was studied with defferent annealing contions: dew point,cooling temperature, cooling rate, as well as wettability characteris-tics. The oxide was characterized by FE-SEM, EPMA, AES, and XPS.

11:00 AMOn the Galvanizability of Si-Bearing TRIP SteelsN. Gao*, D. Liu, N. Tang, Teck Cominco Metals Ltd., Canada; R. Park,POSCO, South Korea

Two TRIP (Transformation Induced Plasticity) steels with composi-tions of 0.147C-0.49Si-2.56Mn and 0.148C-1.49Si-1.84Mn (wt.%)were hot-dip galvanized in zinc baths containing various Al contentsusing an Iwatani simulator through a direct reduction process. Thegalvanizability of the two steels was related to their surface features inthe as-annealed condition which were analyzed using X-ray photo-electron spectroscopy (XPS), glow discharge optical emission spec-trometry (GDOES), and field emission scanning electron microscopy(FE-SEM). The steel galvanizability was strongly affected by the mor-phology and nature of the surface oxides which, in turn, were largelycontrolled by the steel composition, especially the Mn/Si ratio.

11:20 AMEffect of Galvanizing Heat Treatments on the Microstructure andProperties of Al-Si TRIP-assisted Steels during PlasticDeformationY. Bian*, H. S. Zurob, J. R. McDermid, McMaster University, Canada

Galvanizing is essential for TRIP-assisted steels to be used in automo-tive manufacturing. This requires the heat treatments produce notonly surfaces compatible with the galvanizing process but also the re-quired microstructure and mechanical properties. Two galvanizableAl-Si TRIP steels were heat treated using a galvanizing simulator. Theresulting phase constituents and their evolution as a function ofstrain were investigated using SEM and XRD. This was linked to theworking hardening behaviour with a focus on the relative contribu-tions of isotropic hardening and kinematic hardening investigatedthrough unloading/reloading tests. The back stress increases parabol-ically with the increasing prestrain. No saturation of the back stresswas found for the strain levels tested due to the TRIP effect.

Iron & Steel: Recent Developments in SteelProcessing

Surface TreatmentRoom: 329Session Chair: Matthew Merwin, U.S. Steel Research &Technology Center

9:40 AMGas Carburization of Reduced Metal Oxide StripL. B. Cerully*, T. H. Sanders, Georgia Institute of Technology, USA

A technique was developed for the gas carburization of thin tape(~200-500μm final thickness) of magnetite (Fe3O4) reduced toiron in order to produce steel microstructures. Tape is made viathe mixing of metal oxide powders, a binder (A4M Methocelbinder, Dow Chemical Company) and lubricant (100S Pegosperse,Lonza Group Ltd.) to a paste and then the subsequent extrusion ofthe paste through die of varying dimensions. Samples are fully re-duced and sintered in a 10% hydrogen atmosphere over a period of24 hours. Carburization occurs, post-reduction, in a CO/CO2 at-mosphere at 1000°C such that the carbon content reaches the eu-tectoid composition without the occurrence of metal dusting. Thesamples are austenitized such that a homogenous carbon contentexists throughout the sample. Subsequent cooling of the carbur-ized tape results in steel microstructures which display comparablemechanical and microstructural properties as conventionally madegrades.

10:00 AMMicrostructure and Properties of Low-temperature-carburizedA286 Fe-base SuperalloyR. Sharghi-Moshtaghin, G. M. Michal, F. Ernst, H. Kahn, A. H. Heuer*, CaseWestern Reserve University, USA; F. J. Martin, T. J. Lemieux, T. M. Newbauer,B. A. Bayles, P. M. Natishan, US Naval Research Laboratory, USA

A286 is an austenitic iron-base superalloy that is used for applicationsrequiring a ductile, high-strength material. It can be age-hardened toa high strength level, due to the formation of coherent precipitates. Wehave applied a low-temperature gas-phase carburization process pre-viously developed for austenitic stainless steels to this alloy, which in-creases the surface carbon concentration to ≈12 atomic % and thesurface hardness from 350 to ≈1000 HV. Improvements are antici-pated in fatigue resistance, owing to biaxial compressive stresses gen-erated by the high concentration of interstitial carbon. Transmissionelectron microscopy revealed the presence of lath-like carbide precip-itates with a metal concentration near to that of the alloy matrix, butwith appreciable rejection of Ni from the precipitates. Surprisingly,these carbide precipitates are not detrimental to resistance to pittingcorrosion, which is greatly increased, as determined by potentiody-namic cyclic polarization.

10:20 AMMicrostructural and mechanical properties of nitrided Duplexstainless steelR. Giri*, J. Solberg, NTNU, Norway; R. Hoel, MoTech Plasma a.s , Norway

Nitriding is a technique of growing use to introduce elemental nitro-gen to the surface of metals for obtaining very hard surface layerswithout substantial modification of the bulk material properties. Inthe present study, the effect of nitriding on microstructural and me-chanical properties for duplex stainless steel has been investigated.The results show that the microhardness of the stainless steels in-creases significantly after nitriding e.g. Vickers hardness value of nitr-ited duplex stainless steel is 2015 HV while the value for untreatedduplex stailess steel is 305 HV at a load of 25g. The microstructuralfeatures/elemental concentration of nitrited and untreated samplesinvestigated through SEM, TEM coupled with EDS and EPMA will be

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 45

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania46

presented. The effect of nitriding on corrosion properties in term ofcritical pitting temperature has been studied. A possible correlationbetween microstural features,mechanical and corrosion propertieswill be put forward and discussed in the presentation.

10:40 AMEffect of Thermal Cycling on Hardness of Plain Carbon SteelsA. Elmaryami*, The Higher Institute of Mechanical and ElectricalEngineering, Libya

Thermal cycling tests were carried out on carbon steel up to 1.05 C%. A single run was performed at upper temperature of 500 °C andlower temperature of 30 °C in different media (water, sea water, andoil). For several numbers of cycles up to 30 cycles for an accurate de-termination of heating and cooling times. The effect of thermal cy-cling on the hardness were evaluated, from the obtained test results, itwas found that: The hardness decreased with increasing the thermalcycling for both the annealed and tempered samples in all media(water, sea water, and oil), but this decreased in hardness very smalland can be neglected.

Iron & Steel: Steel Product Metallurgy andApplications

Press-Hardening of SteelsRoom: 330Session Chair: Roger Pradhan, ArcelorMittal Steel

9:40 AMHot stamping of ultra high strength steels as a key technology forlightweigt construction (Invited)J. G. Lechler, M. Merklein*, LFT, Germany

Within hot stamping of ultra high strength quenchenable Boron-Manganese-steels sheet metal component with strength higher than1500 MPa can be produced in a one step forming operation. The rea-son for this is given by the combination of hot forming and quench-ing, which happen simultaneously. This paper will focus on theprocess chain of hot stamping, both variants direct and indirect, in-cluding information about the influencing parameters that have to betaken into account, as well as the material behaviour within hotstamping and the resulting materials mechanical properties. For this,aspects as for example influence of the austenitization conditions andparameters, the heat transfer between tool and blank, the flow behav-ior under different load conditions, failure of the material and the oc-curring friction will be discussed. Using the method of Finite Ele-ment Analysis (FEA) the meaning of all of the mentioned topics willbe underlined.

10:00 AMPhysical Metallurgy of Hot Press Forming Ultra High StrengthSteel (Invited)D. Fan, H. Kim, B. C. De Cooman*, Pohang University of Science andTechnology, South Korea

In this paper, the physical metallurgy principles of the hot pressforming process are reviewed. The effect of composition on CCTcurves of CMnB hot press forming steels is discussed taking the de-formation into account. Moreover the thermo-mechanical behaviorof press hardenable B-added CMn steel is reviewed in detail. The in-fluence of deformation temperature and strain rate on the flowstress during press forming and the final room temperature me-chanical properties will be discussed. Detailed in-situ transforma-tion studies of strained press forming steel grades will also be re-ported. The issues related to coatings on B-alloyed CMn hot pressforming steel will be critically reviewed. In particular the combinedeffects of thermal cycle and deformation on the degradation of theAl-10%Si coating will be discussed in detail. Finally, the effect of the

static strain ageing processes occurring during the paint baking cycleon the in-service mechanical properties of press hardened steel willbe presented.

10:20 AMEvolution of Phases and Microstructure During Heat Treatmentof Aluminized Low Carbon Steel (Invited)F. Jenner*, M. E. Walter, The Ohio State University, USA; R. M. Iyengar, R. L.Hughes, Severstal, NA, USA

Diffusion processes for Al-Si coatings on low carbon sheet metal steelsduring austenizing have been investigated. Temperature profiles wereimposed through closed-loop control of a motorized linear slide and atube furnace. Samples with varying heating slope, hold temperatureand hold time were heat treated, and then analyzed with scanningelectron microscopy and energy dispersive spectrometry. The evolu-tion of the coating is tracked by following the formation of 7 main mi-crostructural regions. The effects of the various heat treatment pa-rameters are evaluated. The postprocessed and condensed dataenhances the understanding of the diffusion process in order to opti-mize the heat treatment.

10:40 AMNumerical Process Design of Hot Stamping Processes Based onVerified Thermo-mechanical Characteristics (Invited)H. Karbasian*, A. Brosius, A. Tekkaya, University of Dortmund, Germany; J.Lechler, M. Merklein, M. Geiger, University Erlangen-Nuremberg, Germany

This paper presents several Finite Element Simulations of hot stamp-ing processes by means of experimentally calculated material andprocess data for different stages of the process design. The process andmaterial parameters used in models were optimized with a sensitivityanalysis and by means of an experimental analysis. The identificationof interaction between the thermal and mechanical parameters wasbased on design of experiments. This statistical method ensured an ef-ficient analysis of process parameters consisting of heat transfer coef-ficients, thermal and mechanical characteristics of material. Insightsfrom design of experiments need to be applied in order to enable anefficient FE modeling of hot stamping for process optimization andprocess design.

11:00 AMMaterial and Design Considerations for Hot-Stamped Boron SteelComponents in Automotive StructuresR. Mohan Iyengar*, R. L. Hughes, Severstal North America, USA

The demand for fuel economy and the stringent requirements on au-tomobile safety have required automakers to emphasize strength overstiffness in designing light-weight body structures. The change in em-phasis has necessitated the exploitation of ultra high-strength steelsto achieve improved crashworthiness and durability in automotivevehicles. In this paper, the viability of hot-stamped boron steels inhigh-performance automotive structures will be discussed. A briefdiscussion of hot-stamping process will be followed by recent me-chanical property data that underscore the superiority of boron steelsin enabling the development of safe and fuel-efficient vehicles. Therelatively low-carbon and low-alloy content of boron steels enablebetter weldability compared with high-carbon and high-alloy steels.

11:20 AMDelayed Cracking in Ultra-high Strength Automotive Steels:Damage Mechanisms and Remedies by Micro-structuralEngineeringH. Mohrbacher*, NiobelCon, Belgium

The amount of high strength steel used in body-in-white (BIW) ap-plications is steadily increasing. Simultaneously the share of ultra-high strength steel is gaining share as well. However, concerns by

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 46

Mo

nd

ay A

M

www.matscitech.org 47

several carmakers have been brought forward about delayed crack-ing of such ultra-high strength steels especially under the simultane-ous condition of mechanical stress and hydrogen pick-up due towelding or corrosion processes for instance. The present paper de-velops an approach to these concerns by looking at the origins andmechanisms of delayed cracking. Then the issue of hydrogen in-duced cracking is considered. Based on the substantial experiencesavailable from other fields like pipeline and engineering steels,guidelines are developed for the micro-structural engineering ofultra-high strength automotive sheet with reduced sensitivity for de-layed cracking.

Materials & Systems: Advances in Biomedicaland Biomimetic Materials

Biomimetic MaterialsRoom: 333Session Chair: Prashant Kumta, University of Pittsburgh

9:40 AMToughening Concepts from Natural Rigid Composites (Invited)G. Mayer*, University of Washington, USA

The mechanisms underlying the toughening exhibited in the nacrestructure that are found in the shell of the red abalone and in the con-centric ring structures of the spicules of a Hexactinellid sponge havebeen studied under several different loading conditions. Commonal-ities have been found in the manner in which toughening takes placein both systems, and it has been found that crack diversion, crackbridging, creation of new surface area, and other toughening mecha-nisms occur in both systems. In the same vein, thin protein layers andarchitecture were found to play controlling roles in energy dissipationin these structures.

10:00 AMBioinspired Design of Dental Multilayers (Invited)W. O. Soboyejo*, Princeton University, USA

This talk presents the results of a combined experimental, analyticaland computational materials effort to use knowledge of natural teethin the design of dental multilayers. Inspired and guided by the func-tionally graded structure of the dento-enamel-junction (DEJ) be-tween the enamel and dentin layers in natural teeth, mechanics mod-els are used to explore the effects of graded architectures on the stressdistributions and crack driving forces in possible layered architec-tures that are relevant to dental restorations. A physics-based model isalso developed for the estimation of pop-in loads and fatigue livesover a wide range of clinically relevant loading rates and frequencies.Micron-scale, functionally graded architectures, are then used to testout the loading rate dependence of the pop-in loads, and the stress-fatigue life behavior of bio-inspired dental multilayered architectures.The implications of the results are discussed for the design of inter-faces between biomedical implants and soft/hard tissue.

10:20 AMCrab Shell based BiomaterialsO. C. Wilson*, Catholic University , USA; A. Gugssa, Howard University, USA;P. Mehl, Catholic University, USA; W. Anderson, Howard University, USA

Crab Shell integument is a very unique biomineralized tissue thatserves as the exoskeleton for crustaceans. Crab shell is usuallytreated as a waste by product from the lucrative Blue Claw crabharvest. However, it is worthwhile to take a second look at this ma-terial and garner some additional uses for this versatile material.Crab shell contains the mineral phase calcium carbonate as themajor component (60-80 wt%), and the remaining componentsinclude the polysacharide chitin and various proteins. The crabshell serves various support and functional roles in shell metabo-

lism, repair and renewal. Crab shell can be prepared in variousmanners to enhance its activity. It can be crushed into particulate,demineralized, deproteinated, and the mineral phase can be con-verted from calcium carbonate to calcium phosphate by aging inphosphate solution. A number of different applications for crabshell and derivatized crab shell ranging from enhanced cell growthsubstrate to bone tissue engineering scaffold will be presented inthis talk.

11:00 AMBiomimetic synthesis of nanosized Hydroxyapatite and itspolymorphsS. K. Soni*, National chemical Laboratory, India

In the present study, the exciting possibility of a novel bio-inspiredenzymatic synthesis of nanosized Hydroxy apatite (HAP)Ca10(PO4)6(OH)2 and its polymorphs (β Tri calcium Phosphate(βTCP) and Di calcium Phosphate(DCP) ) using cheap agro-basedwaste materials i.e. wheat bran and a novel extra cellular enzyme Phy-tase, produced by solid state fermentation of fungus Aspergillus nigerNCIM 563 is demonstrated. The as prepared apatite powder with~100 nm interconnected hollow spheres capped by stabilising pro-teins devoid of any contamination of carbonate was synthesized bythe hydro catalytic action of phytase on phytic acid.Biomimic synthe-sis of nanosized biocomposites using novel enzymes from micro or-ganisms starting from potential cheap agro-industrial waste materialsis an exciting possibility and could lead to an energy-conserving andeconomically viable green approach towards the large-scale synthesisof crystalline artificial bone nanomaterials.

11:20 AMBio-inspired Synthesis of Mineralized Collagen Fibril, the BasicBuilding Block of Collagenous Mineralized Tissues (Invited)E. Beniash*, A. S. Deshpande, University of Pittsburgh, USA

Mineralized collagen fibrils constitute a basic structural unit of min-eralized tissues such as dentin and bone. Understanding the mecha-nisms of collagen mineralization is vital for development of new ma-terials for the hard tissue repair. We carried out bio-inspiredmineralization of collagen fibrils using poly-l-aspartic acid, as ananalog of non-collagenous acidic proteins. TEM and SAED studies ofthe reaction products revealed stacks of ribbon-shaped apatitic crys-tals, deposited within the fibrils with their c-axes co-aligned with thefibril axes. Such structural organization closely resembles mineralizedcollagen of bone and dentin. We demonstrate that the interactionsbetween collagen and poly-l-aspartic acid are essential for the miner-alized collagen fibrils formation. These results provide new insightsinto basic mechanisms of collagen mineralization and can lead to thedevelopment of novel bio-inspired nanostructured materials for hardtissue repair.

11:40 AMPreparation of Magnetic Microspheres by Modified Cross-linkingTechniqueM. A. Elblbesy*, M. Ahmed, B. Hefne, Medical Research Institute, Egypt

Magnetic microspheres have long been of interest in biomedical ap-plications including magnetic resonance imaging for clinical diagno-sis, hyperthermia anti-cancer strategy and magnetic drug targeting.Magnetic microspheres have potential use as magnetic seeds for drugdelivery. In this study, the magnetic microspheres are prepared basedon chitosan using suspension cross-linking technique for use in theapplication of magnetic carrier technology. The size of magnetic mi-crospheres are studying by controlled the temperature of the solu-tion. We find that optimize temperature is about 40°C and give amagnetic microspheres in size range of 60-70 micron. The propertiesof magnetic microspheres such as morphology, magnetic properties,thermal stability and functional groups of magnetic microspheres

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 47

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania48

were characterized by different techniques (i.e. SEM, magnetometer,TGA and FT-IR).

Materials & Systems: Advances inCharacterization and Modeling ofCementitious Materials

Advances in Modeling the Behavior of Cement-basedMaterialsRoom: 331Session Chair: Maria Juenger, University of Texas, Austin

9:40 AMModelling of Moisture and Ion Transport in CementitiousMaterials: Assessment of Key Parameters (Invited)V. Baroghel-Bouny*, T. Q. Nguyen, Laboratoire Central des Ponts etChaussées, France; P. Dangla, Paris Est University, France; M. Thiery,Laboratoire Central des Ponts et Chaussées, France

Within the framework of the description and the prediction of mois-ture and/or ion transport in concrete, numerical models have beendeveloped on the basis of well-identified physical/chemical mecha-nisms. Key material properties are involved in the theoretical descrip-tion and are therefore required as input data in the models. The pres-entation will focus on the assessment of these properties, such astransport properties and fluid-matrix interactions. In particular, inthe absence of experimental data, indirect methods, based on numer-ical inverse analysis performed by means of a multi-species transportmodel in saturated conditions or a moisture transport model, areproposed for the assessment of chloride binding isotherm or liquidwater permeability, respectively. The multi-species model involves thespecies Cl-, OH-, Na+ and K+, and is based on the Nernst-Planckequation.

10:00 AMCharacterization of Plastic Shrinkage Parameters for Fresh AlkaliResistant Glass Fiber Reinforced ConcreteM. Bakhshi, C. Soranakom, B. Mobasher*, Arizona State Univesity, USA

A testing protocol and theoretical model for plastic shrinkagecracking in the presence of Alkali Resistant Glass (ARG) fibers ispresented. Concrete mixtures were cast in thin molds and exposedto the vacuum evaporation. Water evaporation was recorded up to24 hrs and cracks were identified by microscopy. Effect of w/c andfiber content were investigated under vacuum drying. Con-strained nonlinear optimization was employed to back-calculatediffusion and convective moisture transfer coefficients at eachtime step. A desorption isotherm, Kelvin equation and Power’sporosity model were used to relate moisture concentration to in-ternal humidity, capillary stress, and macroscopic stress, respec-tively. The results show the significant effect of ARG fibers in de-laying cracking time and minimizing crack width. The proposedtesting protocol and theoretical model show a great potential ascharacterization tools for evaluating fresh concrete mixtures sub-jected to drying.

10:20 AMMulti-Scale Study of Alkali Silica Reaction in CementitiousMaterialsA. Bonakdar, B. Mobasher*, S. K. Dey, Arizona State University, USA

Implementing partial substitution of cement with pozzolans in ce-mentitious materials is known to be effective in controlling the ASRexpansion by altering the chemical reactions and improving thetransport properties, however multi-scale models to describe this roleis still lacking. In this study, microstructural studies including ESEMand quantitative EDS were used with the experimental data from

ASTM C 1567 test method for different flyash blended cements to de-velop a physico-chemical model based on the morphology and com-position of different silicate glass structures. Different silica gels withvarious Ca-Na-Si-O phases and morphologies were modeled as net-works of SiO44- with different numbers of average bridging oxygens.Results from both microscopic and macroscopic expansions showedthat for preventing the formation of expansive gels, the quantities ofacidic oxides (mainly SiO2 and Al2O3) should be increased inblended cement mixture while basic oxide (mainly CaO) should bedecreased.

11:00 AMInsight into the mechanism by which SRA reduces dryingshrinkage in cementitious materialsZ. C. Grasley*, C. Leung, Texas A&M Univ., USA

Shrinkage reducing admixtures (SRA) are surfactants that reduce thesurface tension of water. When added to fresh cementitious materialsor applied as topical agents to hardened material, drying shrinkagemay be substantially reduced. The means by which SRA reduces au-togenous shrinkage (from self-desiccation) are clear, but dryingshrinkage is a more complex phenomenon. Experiments measuringthe shrinkage of Vycor glass during step-wise desorption of watervapor (with varying levels of SRA in the pore solution) have pro-vided insight into the mechanism by which SRA reduces dryingshrinkage.

11:20 AMSurface layer development of synthetic fly ash glass hydrating inalkali and alkaline solutionW. Bumrongjaroen*, R. A. Livingston, J. S. Schweitzer, I. S. Muller, CatholicUniversity of America, USA

Preliminary results show that fly ash reactivity depends on reactionsoccurring at the fly ash glass-solution interface. The leaching behav-ior of three synthetic fly ash glasses in alkali and alkaline solution isinvestigated. The variable is the type of alkali metal (K, K+Ca, Ca,Li) which its concentration simulates the condition present in Port-land cement. The solution was analyzed at different time to observeleaching behavior. The glass surface after the leaching was examinedby means of XRD, and SEM to obtain information on leached layerand phase formed at the interface. It is found that the extent ofetching of glass depends on the pH of solution. The disintegrationof silicate structure of glass occurs in strong base system. No crys-talline phase is found on its glass surface as the glass disintegratesrapidly. In LiOH and Ca(OH)2 system, some new phases areformed at the leached layer which may obstruct the further etchingof glass.

11:40 AMStudy on the Key Factors of Affecting Rheological Performance ofAlkali Activated Carbonatite-slag Grouting PastesQ. Wu*, South China University of Technology, China

The rheological performance of alkali-activated carbonatite-slagpastes (AACSGP) and the effect of modulus, concentration ofsodium silicate solution and content of slag and BS addition on itsrheological performance were studied. The results show that yieldstress f and plastic viscosity η of AACSGP increase with increasing ofslag and BS addition and the concentration of sodium silicate solu-tion and with decreasing of the sodium silicate modulus. It has beenshown that AACSGP has high rheological performance when the pa-rameters of the raw materials are as the following: sodium silicatemodulus 1.6, concentration of sodium silicate solution 35%, slag ad-dition amount 30% and retarder addition amount 4.5%. The opti-mum formulation with mass ratio is that carbonatities powder: slagspowder: sodium silicate solution: retarder (solid)=70: 30: 80:30×4.5%=1: 0.43: 1.14: 0.0193.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 48

Mo

nd

ay A

M

www.matscitech.org 49

Materials & Systems: InternationalSymposium on Innovative Processing andSynthesis of Ceramics, Glasses andComposites

Films and CoatingsRoom: 336Session Chair: Shriram Ramanathan, Harvard University

9:40 AMSynthesis of Thin Film Metal-Oxides under Photon Irradiationand Structure-Property Relationships (Invited)S. Ramanathan*, Harvard University, USA

Thin film oxides play a key role in several advanced electronics andenergy technologies such as alternate gate dielectrics, memory de-vices and functional membranes in energy generation. Developingnovel routes for synthesis of oxide thin films with controlled struc-ture and stoichiometry is therefore of great importance. In this talk,we will present results from our on-going work on synthesis of ultra-thin oxides under photon irradiation with particular emphasis onstructure-property relations. Model systems that will be discussed in-clude ultra-thin zirconia dielectrics synthesized by low temperatureultra-violet ozone oxidation and yttria-doped zirconia films grownby physical vapor deposition methods. The role of photon irradiationduring oxide formation will be discussed in depth along with theirimpact on functional properties. Examples of applications of the pro-cessing technique in advanced transistors as well as solid oxide fuelcells will be presented.

10:20 AMComposite sol-gel coating on porous ceramic substratesM. Touzin*, F. Béclin, Université des Sciences et Technologies de Lille, France

Sol-gel process is commonly used to coat all kind of materials. Butfilms prepared by this method are too thin to rectify the roughness ofmaterials such as porous ceramics. In this study, highly porous ce-ramic substrates have been coated using a sol-gel composite method.Alumina powder is dispersed in a silica sol-gel solution and then dip-coated on the substrate. With accurately control of the sol-gel param-eters (water and solvent ratio, pH and ageing time of the sol) it is pos-sible to obtain crack-free thick films (more than 100 μm in one step).These coatings present good adherence to the substrate, decrease theroughness and also close the open porosity of the substrate. More-over, because of their composite microstructure (crystalline aluminagrains in an amorphous silica matrix), these films present higher me-chanical properties than those prepared by a classic sol-gel process.

11:00 AMSynthesis and characterization of Ce1-x-y/2Lax-y/2CayNbO4 thin filmmembranesF. Vullum*, T. Grande, M. Rotan, NTNU, Norway

A mixture of LaNbO4 and CeNbO4 has been found to exhibit com-plete solid solubility for all compositions. LaNbO4 is a known protonconductor and CeNbO4 possess mixed ionic and electronic conduc-tivity. While the electrical conductivity of the pure materials are notsufficient for application in SOFCs and gas permeable membranes, amixture of the two may exhibit more favorable properties. Powder ofCe0.495La0.495Ca0.01NbO4 and other compositions have been synthe-sized by wet chemical methods, using spray pyrolysis to producepowder from an aqueous solution of La-EDTA, Ce-citric acid andNb-malic acid mixed at the desired stoichiometric ratios. A methodfor preparing asymmetric dense membranes has been developed,where thin films down to 8 μm are obtained by spray coating aporous support synthesized from either the same material as the thinfilm or a material with similar thermal expansion coefficient. Mem-

branes have been characterized with respect to microstructure andhydrogen permeability.

11:20 AMNovel Method to Spray WC-Co Using Portable Low Pressure ColdSpray TechnologyJ. Villafuerte*, CENTERLINE WINDSOR LTD, Canada

Cold spray is a new solid-state spraying process capable of producingthick metallic coatings or freestanding deposits on a diversity of sur-faces at low temperatures, thus avoiding thermal effects associatedwith conventional thermal spray. However, the use of cold spray hasbeen limited to metals and other materials displaying a certain levelof ductility. A large number of coating applications call for a combi-nation of corrosion, wear, and thermal resistance. The use of HVOFin spraying WC-Co has been particularly widespread to replace hardchrome plating in light of recent OSHA regulations limiting the useof processes that release Hexavalent chromium. In this paper, wepresent a different method to cold spray WC-Co cermets using aportable low-pressure system. The coatings show attractive physicaland mechanical properties, without the aggravations associated withelevated process temperatures such as decarburization, oxidation,metallurgical transformations, and residual stresses.

11:40 AMFaradayic Process for Electrophoretic Deposition of ThermalBarrier Coatings for Use in Gas Turbine EnginesH. McCrabb*, J. W. Kell, Faraday Technology, USA; B. Kumar, University ofDayton Research Institute, USA

Faraday is developing an electrically mediated electrophoretic depo-sition process (Faradayic EPD) for thermal barrier coatings. Thisprocess is capable of creating a uniform coating of yttria-stabilizedzirconia (YSZ), in a non-line of sight fashion, for use in thermal bar-rier systems in natural gas and synthesis gas environments. Ni-basedsuperalloy substrates, coated with an MCrAlY bond coat, were de-posited on and underwent a binder burnout and sintering process.The samples were then subjected to surface roughness measurements,microstructural examination, thermal conductivity measurements,thermal cycling tests, and other appropriate tests of merit to deter-mine their feasibility for use in gas turbine engines. Experimentalstudies showed that the process could uniformly deposit YSZ withgood surfaces, decreased edge effects, and with properties consistentwith similar systems processed through other methods.

Materials & Systems: Glass and OpticalMaterials

Glass and Optical Materials IRoom: 334Session Chair: Steve Feller, Coe College

11:00 AMLyon’s Bluff Glass: Chemical Analysis and Laboratory Replicationof an Archeological Sample (Invited)R. A. Palmer*, Y. Xia, E. Kazal, E. Peacock, Mississippi State University, USA

A glass artifact was found at the Lyon’s Bluff site, a large mound andvillage complex located in northeastern Oktibbeha County, Missis-sippi. Stratigraphic excavations, ceramic styles, and radiocarbon datesindicate continuous occupation of the site from ca. A.D. 1200 to atleast A.D. 1650. In an effort to establish the archaeological prove-nance of the glass, chemical analysis was done by laser ablation – in-ductively coupled plasma – mass spectrometry (LA-ICP-MS), induc-tively coupled plasma – atomic emission spectrometry (ICP-AES),and energy dispersive spectrometry in a scanning electron micro-scope (SEM-EDS). In this paper, we present basic data on the chemi-cal makeup of the glass, conjectures as to the origin of the glass, andattempts to replicate the material in the laboratory.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 49

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania50

11:40 AMDensity Functional Modeling of Disordered LayeredAluminosilicatesC. E. White*, J. L. Provis, D. P. Riley, G. J. Kearley, J. van Deventer, TheUniversity of Melbourne, Australia

Crystalline materials are ideally suited to ab initio modeling due totheir well defined periodic structure. However, in disordered oramorphous materials the periodicity of the structure is much lower,and modeling is therefore much more strictly limited by computa-tional considerations. Here, we outline the methodology used tomodel a disordered layered aluminosilicate, metakaolin (partiallydehydroxylated kaolinite) using density functional theory. Thismethodology commences with modeling of the crystalline parentmaterial, kaolinite, in order to validate the computational approachselected. The stepwise transition of the structure from crystalline todisordered is then modeled, ensuring that the structure remains ina physically realistic state throughout the simulated dehydroxyla-tion process. The results obtained provide the first detailed atomicdescription of the structure of metakaolin, and correlate well withexperiment.

Nanotechnology: Controlled Processing ofNanoparticle Structures and Composites

Nanoparticle Sintering IRoom: 408Session Chair: Geoff Brennecka, Sandia National Laboratories

9:40 AMSintering of Nanograin Ceramics (Invited)I. Chen*, University of Pennsylvania, USA

Dense nanograin ceramics are difficult to obtain despite the use ofnanopowders because of coarsening during all stages of sintering.While coarsening during initial stages of sintering is geometricallyand thermodynamically unavoidable, it is now known that graingrowth during final stage sintering can be completely suppressed toreach full densification without coarsening. This is best achieved bytwo-step sintering, in which a second sintering step is performed at alower temperature than in the first step, although other variations arepossible when sintering is aided by an external stress or the ability tofast heat/cool. The practice (see references below, updated by a reviewof the recent literature) and theoretical understanding of these oper-ations are presented in this talk. Nature, 404, 168-71 (2000). J. Amer.Ceram. Soc., 89 [2] 431-437 (2006). J. Amer. Ceram. Soc., 89 [2] 438-443 (2006).

10:20 AMStudies in Creep, Superplasticity, and Fracture Toughness in BulkCeramic Nanocomposites (Invited)A. K. Mukherjee*, University of California, USA

Nanocrystalline materials have demonstrated substantial changes inphysical, chemical, and mechanical properties at severely diminishedlength scales. This length scale effect has been investigated in severalceramic nanocomposites prepared by a variety of processing tech-niques. A liquid polymer precursor derived SiC/Si3N4 nanocompositehas demonstrated one of the lowest creep rates at a referred tempera-ture of 1400°C. A three-phase alumina/zirconia/Mg-spinel ceramicnanocomposite can be deformed in superplasticity at a temperatureas low as 1150°C, when the forming operation is done in an electri-cally pulsed sintering environment. Single-walled carbon nanotube(SWCNT)-reinforced nanocrystalline sapphire composite hasdemonstrated remarkable improvement in fracture toughness. Theresults will be discussed in the context of microstructural informa-tion and rate-controlling deformation mechanisms.

11:00 AMDensification and Properties of spark plasma sintered Y-TZPNanoceramics and WC - ZrO2 Nanocomposites (Invited)B. Basu*, IIT Kanpur, India

In recent times, nanoceramics and nanoceramic composites have re-ceived increased attention in the materials science community. After abrief presentation on interdisciplinary research being carried out in mygroup, some interesting and important experimental results will bepresented to demonstrate two different, but contrasting aspects: a)How SPS route can be utilized to develop ultrahard nanoceramic com-posites (hardness ~ 24 GPa) in WC-based composites? b) Whether SPSroute, in comparison to conventional consolidation route (Hot press-ing) always offers opportunity to develop materials with better materialproperties? Prior to discussing the above issues, our recent computa-tional results, obtained using Finite element simulations to determinethe temperature distribution (both in radial and axial direction), heatand electric flux-field in the powder compact/die/punch assembly dur-ing the spark plasma sintering (SPS) process will be presented.

11:40 AMActivation of Material Transport in Spark-Plasma Sintering(Invited)E. Olevsky*, San Diego State University, USA

Spark-plasma sintering (SPS) carries a potential for the efficient consol-idation of powder materials. Possible mechanisms of the enhancementof consolidation in SPS versus conventional techniques of powder pro-cessing are categorized with respect to their thermal and non-thermalnature. A model for spark-plasma sintering taking into considerationmechanisms of thermally and non-thermally-activated material trans-port is developed. The interplay of mechanisms of material transportduring SPS is considered: surface tension-, electromigration- and exter-nal stress-driven grain-boundary diffusion, surface tension- and exter-nal stress-driven power-law creep, and temperature gradient-driventhermal diffusion. The obtained results are applicable to the amplerange of powder consolidation techniques which involve high localtemperature gradients and high heating rates. The modeling resultsagree well with the experimental data on SPS of a metal (aluminum)and ceramic (alumina) powders in terms of SPS shrinkage kinetics.

Nanotechnology: Nanotube-Reinforced MetalMatrix Composites

Processing Techniques for Nanotube-ReinforcedMMCs IRoom: 409Session Chair: Indrajit Charit, University of Idaho

11:00 AMFabrication and Thermomechanical Properties of CarbonNanotube/Metal Composites by Spark Plasma Sintering Method(Invited)A. Kawasaki*, Tohoku University, Japan

Multiwall carbon nanotube (MWNT) materials are attractive becausethey possess excellent thermal conductivity and mechanical proper-ties. However, few reports exist that focus on improving the thermalconductivity of MWNT by combining it with a metal matrix. Thus toimprove the thermal conductivity, a nickel-matrix composite withMWNT was prepared by slurry mixing process using ethanol as a sol-vent. Using spark plasma sintering (SPS), MWNT/Nickel nanocom-posites were fabricated and the fabrication conditions were investi-gated. The sintered relative densities of the composites containing upto 5vol% of MWNT were above 99%. The thermal and electrical be-haviors of the MWNT/Nickel composites were determined using thelaser flash and van der Pauw methods, respectively, and were found tobe anisotropic. The thermal conductivity was found to increase by10% for the composition with 3vol% MWNT.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 50

Mo

nd

ay A

M

www.matscitech.org 51

11:40 AMMultiwalled Carbon Nanotube Reinforced Aluminum CompositeCoating via Cold Kinetic SprayingS. R. Bakshi*, Florida International University, USA; G. D. McCartney,University of Nottingham, United Kingdom; S. Seal, University of CentralFlorida, USA; A. Agarwal, Florida International University, USA

Multiwalled carbon nanotube (MWNT) reinforced Al compositecoatings were synthesized using cold gas kinetic spraying. Spray dry-ing was used to disperse MWNT in micron-sized gas atomized Al-Sieutectic powders. Spray dried powders containing 5wt% MWNTwere blended with pure Al powder to give overall MWNT composi-tions of 0.5wt% and 1wt%. Coatings of the order of 0.5 mm thickwere deposited. Fracture surfaces indicated uniform distribution ofMWNT. MWNTs were shorter in length as they fractured due to im-pact and shearing between Al-Si particles and the Al matrix duringthe deposition process. Necking and cup and cone fracture of MWNTwith 70% reduction in the cross section area was seen which is com-parable to mild steel. Peeling off of outer walls of MWNT was ob-served. Nanoindentation shows a distribution in the elastic modulusvalues from 40-229 GPa due to microstructural heterogeneity of thecoatings that comprise pure Al, Al-Si eutectic, MWNTs and smallamount of porosity.

Processing & Product Manufacturing:International Symposium on Ceramic MatrixComposites

Carbon Nanotube and Nano-compositesRoom: 413Session Chairs: Koichi Niihara, Nagaoka University of Technology;Richard Todd, University of Oxford

9:40 AMNanocomposite Ceramic Materials with UniqueMultifunctionality (Invited)K. Niihara*, T. Nakayama, Nagaoka University of Technology, Japan; T.Kusunose, Osaka University, Japan

Concentrated researches have found that the nanocomposite conceptplay important roles not only in structural ceramics but also in variouskinds of functional ceramics such as electronic ceramic materials. Andthey also suggested that the nanocomposite structure would give us vari-ous kinds of multifunctional materials. Based on these information, at-tempts were made to develop the multifunctional ceramic materials, andvarious kinds of new multifunctional ceramic materials were successfullydeveloped, which showed the improved strength and toughness togetherwith new functions such as machinability like metals, electrical conduc-tivity and stress & fracture sensing function and so on. In the presenta-tion, we will mainly discuss recent results on multi functional materials,in special, multifunctinalized ceramic based nanocomposite materials. Infinal, our new materials design concept on molecular/cluster/lattice levelcomposites and some results on them will be presented and discussed.

10:20 AMFabrication of the Nanotube/Nanoparticle composites and itsThermal PropertiesT. Nakayama*, H. Kim, M. Terauchi, Nagaoka University of Technology,Japan; T. Sekino, Tohoku University, Japan; T. Suzuki, H. Suematsu, K.Niihara, Nagaoka University of Technology, Japan

In 1998, Kasuga et al have succeeded in the synthesis of self organizedtitania nanotubes (TNT) using easy and low temperature chemicalprocessing without any template. Since then we have reported thestudies result on TNTs and its applications. These modifications ofthe TNTs are believed to realize advanced and high performancenano-materials which will serve as energy and environmental materi-als. The large water is discharged by the heating, because the TNT has

the large adsorption water. It becomes possible that this thermal be-haviour is utilized by the combination with nanoparticle. The newliquid emission characteristic by the combination of TNT andnanoparticles will be discussed.

11:00 AMProcessing and properties of CNT/glass-ceramic andCNT/alumina composites (Invited)R. I. Todd*, B. T. Chu, University of Oxford, United Kingdom; J. Zhang,Wuhan University of Technology, China; N. Grobert, M. L. Green, Universityof Oxford, United Kingdom; Z. Fu, Wuhan University of Technology, China

The literature shows that the production of uniform dispersions ofundamaged nanotubes in CNT/glass and CNT/ceramic compositeshas proved difficult and there have been conflicting reports of theproperties that such composites exhibit. The first part of this presen-tation describes a sol-gel based route for the production ofCNT/glass/ceramic composites that overcomes many of the process-ing problems and presents some of the thermomechanical propertiesof the resulting well dispersed composites. The second part concernsthe response to hardness indentation of MWNT/alumina compositesproduced by a powder route under different SPS densification condi-tions. The results show that a wide variety of cracking responses canbe obtained using the same starting powder depending on (i) thefinal density, (ii) the processing temperature and (iii) the indentationload, thus explaining some of the discrepancies between results in theliterature. Possible mechanisms for the observations are discussed.

11:40 AMAlignment Behavior of Carbon Nanotubes in CNTs/OxideCeramic System using Magnetic FieldB. Jang*, Y. Sakka, National Institute for Materials Science (NIMS), Japan; C.Lyszyk, L. Gendre, University of Rennes I, France

This work describes the alignment behavior of carbon nanotubes(CNTs) in strong magnetic field and the colloidal dispersion of CNTsin the oxide ceramic suspension, such as Al2O3, ZrO2 and hydroxyap-atite. Commercially available multi-walled carbon nanotubes(MWNT) with 10~100 nm in diameter and 10~30 um in length wereused. 0.001~10 wt% of as-received or length-controlled CNTs weresuspended in aqueous solution and ceramic suspension. A strongmagnetic field of 12 T was also applied to the oxide ceramic suspen-sions to control the alignment of the CNTs. The degree of dispersionwas found to depend on the properties of the CNTs, pH, Zeta potentiallevel and size of CNTs. In addition, the well-aligned CNTs according todirection of magnetic field were obtained under strong magnetic field.The aligned degree of CNTs depends on the shape of CNTs. Straight-type CNTs show the well alignment rather than curve-type CNTs.

Processing & Product Manufacturing: Micro-Manufacturing: Material Behavior,Deformation Mechanics, Process Control andApplications

Micro-Manufacturing IRoom: 410Session Chairs: Muammer Koc, Virginia Commonwealth University;Omer Cora, Virginia Commonwealth University

9:40 AMSpark plasma sintering and post-sinter annealing of aluminaL. Huang*, University of California, Davis, USA; F. Chen, Wuhan Universityof Technology, China; A. K. Mukherjee, J. M. Schoenung, University ofCalifornia, Davis, USA

Spark plasma sintering (SPS) can be used to sinter and densify ce-ramics with ultrafine grain sizes because of low sintering tempera-tures and short sintering times. In the present study, dense ultrafine

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 51

Mo

nd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania52

alumina ceramic, both with and without dopant additions, has beensynthesized via SPS using select sintering conditions, which includevariations in sintering temperature, heating rate, holding time andsintering stage. In addition, the effects of select post-sinter annealingconditions, including a variety of annealing times and temperatures,on grain growth have been systematically investigated. The kinetics ofgrain growth during sintering and annealing have been evaluatedwith the aid of microstructure evolution studies using scanning elec-tron microscopy (SEM) and phase transition studies using X-ray dif-fraction (XRD).

10:00 AMA Simulation Based Approach for Investigating SolidificationMicrostructure in Beam-Based Solid Freeform FabricationS. Bontha*, Kennametal Inc, USA; N. W. Klingbeil, Wright State University, USA

The success of laser or electron beam-based solid freeform fabrica-tion processes for aerospace applications will ultimately depend uponthe ability to predict and control the microstructure and resultingmechanical properties of the deposit. To this end, this presentationwill summarize a combination of analytical and numerical ap-proaches to modeling beam-based deposition processes. The analyti-cal approach is based on the Rosenthal solution for a moving pointheat source, which yields nondimensional process maps for solidifi-cation cooling rates and thermal gradients (the key parameters con-trolling microstructure). In addition, finite element modeling is usedto include the nonlinear effects of temperature-dependent propertiesand latent heat of transformation, as well as to investigate non steady-state conditions. Results suggest that process variables (e.g., powerand velocity) and size-scale can have a significant effect on solidifica-tion microstructure.

10:20 AMThe use of nano-sized Al2O3-powders in tape casting and its effecton process and product qualityP. Vozdecky*, A. Roosen, Institute of Glas and Ceramics, Germany

In this work the use of nano-sized Al2O3-powders in the tape castingprocess will be evaluated. For the fabrication of tape cast productspowders with average grain sizes between 1 and 3 μm are typicallyused. The transition to nano-scaled powders impedes their process-ing. In this study, nano-scaled Al2O3-powders with medium particlesizes between 30 and 65 nm are used, which were generated bymilling in a commercial attrition mill. From these powders, tape cast-ing slurries were prepared and cast by means of the doctor-bladetechnique. The effect of the powders on the viscosity of suspensionsand slurries, on the casting process as well as on binder burnout anddensification was characterized. Properties like density, microstruc-ture, surface roughness and strength has been measured. The prosand cons on processing and specific product properties by usingnano-sized powders in the tape casting process will be discussed.

11:00 AMEffect of Feature Size on Formability of Thin Sheet Metals atMicro/Meso-ScalesS. Mahabunphachai*, M. Koc, Virginia Commonwealth University, USA

In this study, the effect of the “feature/part size” on material behaviorof thin sheet metals is investigated. Specifically, thin SS304, 51 mi-crometer-thick, were bulged using five different circular dies with thediameter (Dc) between 2.5 and 100 mm. The results of the bulge testsshowed a decrease in the material flow curve with decreasing bulge di-ameter from 100 mm to 10 mm. However, as the bulge size decreasedfurther from 10 mm to 2.5 mm, an inversed relation between the flowcurve and the feature size (Dc) was observed; that is, the flow curvewas found to increase with decreasing Dc. In addition, new materialmodels were developed by introducing the two new size effect param-eters, N and M, to capture the size effects on the material behavior.The predictions based on these models were shown to be in goodagreement with the bulge test results in this study and in the literature.

Processing & Product Manufacturing:Paradigm Shift in the Metals Industry

Paradigm Shift in the Metals Industry IRoom: 411Session Chair: Y. Murty, Cellular Materials International

9:40 AMGlobalization in the Metals Industries: General Considerations(Invited)J. F. Grubb*, ATI Allegheny Ludlum, USA

The Globalization of industry has had significant impact on the met-als industries. Those factors that are common to many of these indus-tries will be explored briefly.

10:20 AMFuture of Magnesium Developments in 21st Century (Invited)R. E. Brown*, Magnesium Assistance Group, Inc., USA

Magnesium as a structural material has experienced a wild ride dur-ing the 20th Century. This next millenium will be as exciting, butmore controlled. Like riding a fast race horse compared to a buckingbronco. Magnesium is the only metal on earth that is available in lim-itless quantities. This fact coupled with magnesium’s inherent lowdensity and great formability will help boost new interest. As light-weight construction becomes necessary for mobile platforms, i.e. au-tomobiles, trucks, aeroplanes, trains, aerospace vehicles, there will beincreasing need to review how the properties of magnesium can beused to supply solutions to some of the industries problems. It willnot be easy, but this paper will address what has been done with mag-nesium in the past century, what is being done today and will suggesta future development program.

11:00 AMChanges driving new product and process developments for theAluminum industry in Space, Aerospace, Automotive andEnvironmental fields (Invited)R. J. Rioja*, J. Liu, R. Kamat, J. R. Smith, Alcoa Inc., USA

Changes facing producers of Aluminum products are summarized.Forces for change are; competition from alternative materials in-creases in the price of fuel and power, globalization and sustainability.Space faces the challenge to increase the size of payloads for access tothe Moon and Mars. Aerospace faces entry of composites. Recentlythe Aluminum content for a mid-size aircraft went from 70% for a777 aircraft to 20% for the new 787 airplane (wt%). This has cat-alyzed the development of new products and structural concepts. Au-tomotive markets face competition from steel, magnesium and plas-tics to reduce weight due to increases in fuel price and mandatedgreen house gas reductions. Hence new alloys and processes havebeen developed to remain competitive. Finally the manufacture ofAluminum products face needed reductions of CO2 emissions andescalating prices of power. Alcoa’s strategy and approach to addressthese issues will discussed

11:40 AMCopper: New Paradigm for an Old Metal (Invited)K. J. Kundig*, Metallurgical Consultant, USA

No metals have served humanity for so long, or in such a large varietyof ways, as have copper and its many alloys. This tradition continuesin the electrical and water-related uses that comprise the largest frac-tions of copper consumption today, but, while copper’s utilizationhas reached record levels in recent years, many of its historic uses haveeroded in the face of substitution by alternative materials. Neverthe-less, copper’s ability to reduce thermal and electrical losses by virtueof the metal’s unsurpassed conductivities promises new applicationsat precisely the historic moment when improved efficiency has gained

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 52

Mo

nd

ay P

M

www.matscitech.org 53

a prominence never seen before. The paper provides examples of re-cent and expected near-term technological advances that exploit thisproperty. The paper additionally describes the copper metals’ antimi-crobial efficacy and the implications this historically well-known butunderutilized property offers in healthcare and other disciplines.

Processing & Product Manufacturing:Processing, Properties and Performance ofComposite Materials

Modeling of Composite MaterialsRoom: 412Session Chairs: Krishan Chawla, Univ. of Alabama at Birmingham;Narendra Dahotre, University of Tennessee

9:40 AMMulti-Scalar Analysis of Area Fractions: Applications forCharacterizing Multi-Component Discontinuously-ReinforcedComposite Microstructures (Invited)J. E. Spowart*, United States Air Force, USA; G. B. Wilks, M. A. Tschopp,General Dynamics Information Technology, USA

The computationally-efficient Multi-Scalar Analysis of Area Frac-tions (MSAAF) technique is reviewed in the context of quantificationof spatial heterogeneity in discontinuously-reinforced composite mi-crostructures. The technique provides a simple multi-scalar descrip-tion of spatial heterogeneity through the derivation of the Homoge-neous Length Scale, which relates the spatial statistics of local areafractions to a microstructural length scale. In this presentation, theMSAAF technique is extended to encompass multi-component com-posite microstructures, i.e. those containing more than one discretereinforcement phase. Specific examples where spatial correlations be-tween reinforcement phases have a direct impact on the physical andmechanical properties of the composite will be given.

10:20 AMThree-Dimensional (3D) Microstructure Visualization and FiniteElement Modeling of Interfacial Decohesion in Particle ReinforcedMetal Matrix CompositesJ. Williams, N. Chawla*, Arizona State University, USA; J. Segurado, J. LLorca,IMDEA, Spain

Composite materials have highly complex microstructures. We havedeveloped a three dimensional (3D) approach to (a) construct a “vir-tual microstructure” in 3D by serial sectioning technique, and (b) fi-nite element modeling using the 3D microstructure as a basis. In thistalk the fundamentals of the 3D virtual microstructure modelingmethodology will be explored. This methodology was used to studythe deformation behavior of SiC particle reinforced metal matrixcomposites. The role of second phase fraction, morphology, and as-pect ratio on deformation was quantified and will be discussed. Theinterfacial decohesion behavior was modeled with user-defined cohe-sive zone elements. The relationship between particle shape and dis-tribution with interface decohesion, as well as the evolution of dam-age in the composite will be discussed.

11:00 AMFlow Simulation to Address Microvoids and Material Variability inLiquid Composite Molding (Invited)S. G. Advani*, P. Simacek, University of Delaware, USA

Flow simulations can routinely predict the flow patterns during theresin impregnation process in Liquid Composite Molding (LCM).One such numerical simulation, Liquid Injection Molding Simula-tion (LIMS) developed at University of Delaware over the last decadecan describe resin infusion in many LCM processes such as RTM,VARTM and Compression RTM. Such simulations have proven use-ful in reducing or eliminating macrovoids by designing an injection

strategy that will ensure that the resin arrives last at the vent. LIMSaddresses the micro flow by coupling the flow in fiber tows with thebulk flow. This paper addresses this multiscale approach and showsits usefulness in reducing microvoids as well. It also analyzes the roleof the permeability data required for successful modeling. Finally, thepaper acknowledges the process variability encountered in LCMmanufacturing and how this variability can be accommodated inprocess modeling and design.

11:40 AMA mixture theory framework for modeling Ionic Polymer MetalComposites actuatorsM. Porfiri*, Polytechnic University, USA

We present a mixture theory framework for modeling Ionic PolymerMetal Composites (IPMCs) and species interactions occurringtherein. The proposed framework accounts for the simultaneous ef-fects of osmotic pressure, hydraulic pressure, and electrostatic forceson IPMCs behavior, and it is applicable to a large variety of IPMCs’geometries and microstructures. The model allows for a quantitativeunderstanding of i) the migration of mobile ions due the electric fieldgenerated; ii) the displacement of the solvent towards the cathodic re-gion; and iii) the expansion of the backbone polymer in the vicinityof the cathodic region.

Keynote & Lectures

ASM/TMS Distinguished LectureRoom: 407

1:00 PMEngineering Material Systems for an Ever Demanding Society(Invited)L. Christodoulou*, DARPA DSO, USA

The demands of the society on materials are growing at an unprece-dented pace. The world expects higher performance, lower cost, ac-celerated implementation cycles, and sustained and reliable use. Tomeet these challenges the materials science community is required toengineer material systems to meet multiple and often conflicting re-quirements at a pace typical of upgrades in the electronics industry(~1-3 years). Yet, to date, structural materials rarely transition fromdiscovery to use in less than 15-20 years. To meet these challenges,materials can no longer be considered as commodity items to belooked up in a handbook meeting some requirement derived from adesign dictated by other considerations. Rather, materials need to bedesigned and engineered for optimum performance in the specificapplication. The a priori design of materials to meet multiple func-tions, accelerated qualification and long-term probabilistic behaviorprediction in service requires that materials are considered as “sys-tems” that incorporate well orchestrated attributes (“subsystems”)operating in unison to achieve the desired combinations of proper-ties. Mechanistic understanding, robust modeling approaches at mul-tiple scales, novel testing protocols and heuristic-based insights allhave an important role to play in this challenge. Engineering materialsystems for the ever-demanding society is within our grasp.

2:00 PMThermal Barrier Coatings (Invited)A. Evans*, University of California Santa Barbara, USA

Abstract Not Available

2:30 PMSuper Alloys (Invited)J. C. Williams*, The Ohio State University, USA

Abstract Not Available

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 53

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania54

Special Topics: ACerS 110th AnniversarySymposium

Emerging TechnologiesRoom: 404/405Session Chair: Brian Sundlof, IBM

2:10 PM3D Silicon Integration (Invited)J. U. Knickerbocker*, P. S. Andry, B. Dang, R. R. Horton, C. S. Patel, R. J.Polastre, IBM - T.J. Watson Research Center, USA; K. Sakuma, IBM TokyoResearch Laboratory, Japan; E. S. Sprogis, IBM Systems and TechnologyGroup, USA; C. K. Tsang, B. C. Webb, S. L. Wright, IBM - T.J. WatsonResearch Center, USA

Three-dimensional (3D) chip integration may provide a path to minia-turization, high bandwidth, low power, high performance and systemscaling. Integration options can leverage stacked die and/or silicon pack-ages depending on applications. The enabling technology elements in-clude: (i) through-silicon-vias (TSV) and thinned silicon wafers, (ii) finepitch wiring, (iii) interconnection between die, (iv) known-good die in-cluding BIST, fine pitch probes and test strategy and (v) power deliveryand cooling solutions. Applications may range from miniaturization forportable electronics like image sensors and cell phones to high perform-ance computing solutions such as servers and super computers. Siliconbased packaging and 3D stacked die technologies have been investigatedover several years of study. Experiments included test vehicle design,build, characterization and modeling. Robust structures and processeshave been developed based on (i) process learning for silicon basedstructures, (ii) assembly process comparisons for fine pitch chip inter-connection, (iii) electrical, mechanical and thermal characterizationand (iv) reliability stress characterization. 3D technology investigationshave included composite, copper and tungsten TSV’s, demonstrationsof fine pitch wiring and interconnections at over 400 interconnectionsper mm2, demonstration of integrated decoupling capacitors at overtwelve micro-farads per cm2 and assembly of structures on silicon pack-ages with ceramic and organic base packages. Examples of robust TSVstructures and characterization, single die with silicon interposers, mul-tiple die on a silicon package and stacked die assemblies are given alongwith highlights of characterization including aspects of electrical, me-chanical and reliability results. This research paper describes recent ad-vances in industry and reports advancements from IBM in the design,technical challenges and progress toward 3D chip integration structures.

2:40 PMMaterials Informatics: An Emerging Technology for MaterialsDevelopment (Invited)R. LeSar*, Iowa State University, USA

Computational materials science has progressed to the point that it isbeing embraced by materials engineering as a key part of the materialsdevelopment process. Often referred to as Integrated ComputationalMaterials Engineering (ICME), this new approach links computationwith experiment and data to enhance and accelerate materials develop-ment. An important component of this integrated approach is materi-als informatics, in which advanced mining and analysis techniques areapplied to experimental (and, potentially, model-based) data as onestep of an information-based process for understanding and exploringmaterials behavior. In this talk, we will review the basic approachesused in materials informatics, will show some selected examples thatdemonstrate their strengths (and weaknesses), and will discuss the rolethat materials informatics plays within an ICME process.

3:30 PMGenerations: The Evolving Landscape of Photovoltaics (Invited)D. Ginley*, National Renewable Energy Laboratory, USA

The talk will discuss the rapidly changing landscape of solar powerproduction and take a look at the emerging technologies and the ma-

terials challenges in current and future technologies. Photovoltaicsoffers great promise as a durable way to directly convert sunlight di-rectly to electricity. Current first generation technologies, predomi-nately crystalline and polycrystalline Si, have begun to make signifi-cant contributions to the worlds energy and are becoming one of thelargest businesses on the planet. However, for silicon to meet the Lev-elized Cost of Electricity (LCOE) may require cost reductions that arevery difficult to obtain. Significantly, there are a number of emergingsecond generation technologies that use thin film semiconductors onlow cost glass substrates to potentially produce power at much lowercost. Some of these most notably CdTe are now cheaper than 1st gen-eration materials. The primary players in this area are CdTe, CuIn-GaSe and thin film amorphous and nano-crystalline Si. These tech-nologies have the potential to be more integratable with existingtechnologies (buildings and homes) and to provide sufficient cost re-ductions but much remains to be done to achieve their full promise.

4:00 PMBeyond the Human Genome Sequence: Translating GenomicKnowledge into Health Benefits (Invited)E. Green*, National Institutes of Health, USA

The Human Genome Project’s elucidation of the human genome se-quence represented a scientific achievement of historic proportions.It also signified a critical transition, as a new powerful foundation ofgenetic information was created for researchers and clinicians totackle complex problems in human biology and disease. Current ef-forts in genomics research are focused on using genomic data andtechnologies to acquire a deeper understanding of biology and to un-cover the genetic basis of human disease. In the coming decades, theseefforts are likely to change biomedical research and the practice ofmedicine in profound ways.

4:30 PMEmerging Technologies Cafe Forum IntroductionB. Sundlof*, IBM Corporation, USA

Immediately following the session will be a discussion forum or Cafein which the speakers, industry, labs, and academia representativescan gather to openly correspond with respect to the challenges thematerials community can influence and focus on for future, makeprofessional contacts, and stimulate the direction of research and de-velopment. There will be five tables set-up in the lecture area, one foreach topic plus a 5th to highlight future emerging technologies. At-tendees will be asked to move from one table to another after 20 min-utes, allowing each attendee the opportunity to sit at 2 tables.

Special Topics: Education and ProfessionalDevelopment

Professional Development/Industrial PerspectiveRoom: 403Session Chair: William Fahrenholtz, Missouri University of Scienceand Technology

2:00 PMOpportunities for Students to Develop Professional SkillsThrough Extracurricular Activity Participation (Invited)R. W. Schwartz*, Missouri University of Science and Technology, USA

In today’s job market, both technical expertise and “soft skills” are ex-pectations employers place on graduates. Abundant opportunitiesexist for today’s student on the typical college campus to develop theother professional skills expected by employers. For example, serviceas an officer in a student organization represents an excellent oppor-tunity for the development of a variety of soft skills. Such service alsoaffords mentoring opportunities for the student, since most studentorganizations have faculty advisors who provide invaluable guidanceand insight. Lastly, accepting the challenge of an officer position af-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 54

Mo

nd

ay P

M

www.matscitech.org 55

fords these opportunities in a relatively repercussion-free environ-ment. In this presentation, the role of service in the professional de-velopment of today’s student is discussed. Skill acquisition from par-ticipation in such activities is reviewed and the importance ofaccepting such challenges is considered.

2:20 PMNew Employees: Beginning an Industrial Career – An IndividualPerspectiveK. E. Howard*, M. E. Buchmann, The Dow Chemical Company, USA

This presentation will discuss, from an individual (with nearly twentyyears of industrial experience) perspective, some of the challenges en-countered when searching for one’s first industrial position as well asparticular skills and experiences industrial employers seek in prospec-tive candidates. Once ‘in the door’, new industrial employees face a ca-reer that’s quite different than most academic experiences, where net-working, mentoring, and timed project delivery join technical acuity asrequisite traits for success. Professional development strategies will beconsidered. Finally, suggestions for students still in university to betterprepare themselves for a career in a global corporation, will be offered.

2:40 PMProfessional Registration of Materials EngineersD. L. Bourell*, University of Texas, USA; J. W. Fergus, Auburn University,USA; D. A. Shifler, Office of Naval Research, USA; S. Nayak, IntelCorporation, USA

In October 2008, the Principles and Practice of Engineering Exami-nation in Metallurgical and Materials Engineering will be offered forthe first time. This exam specification was developed from the Metal-lurgical Engineering examination as a result of changing demo-graphic in the materials engineering community. In parallel with thischange, the licensing process for all engineers is changing because ofchanges in engineering academic curricula and job requirements. Inthis presentation, the benefits of and procedures for obtaining a Pro-fessional Engineering license will be presented. This will include a re-view of recent and upcoming changes in the registration process.

3:00 PMPractical Tips for Prosecuting Patent Applications and RecentDevelopments in U.S. Patent LawD. M. Longo*, Finnegan Henderson LLP, USA

Patent rights are used protect inventions and allow inventors to profitfrom them. These rights, however, can be lost or diminished in manyunexpected ways. This talk will provide an overview of obtaining aU.S. patent and how to avoid potential pitfalls along the way, includ-ing practical tips for prosecuting patent applications before the U.S.Patent & Trademark Office. In addition, this talk will cover recent de-velopments in U.S. patent law concerning determinations of whatmay or may not be “obvious” in light of the U.S. Supreme Court’s de-cision in KSR v. Teleflex. I will discuss how this decision (and subse-quent decisions by the Court of Appeals for the Federal Circuit) mayaffect currently pending patent applications and strategies for filingand prosecuting new patent applications.

Undergraduate ResearchRoom: 403Session Chair: William Fahrenholtz, Missouri University of Scienceand Technology

3:40 PMResearch Your Way to Success:Where To Go and Why You Should(Invited)K. White*, Brookhaven National Laboratory, USA

It is no secret. The success of America is largely based on science, tech-nology, and innovation. Our elected officials know this, corporateAmerica knows this, and so do the many federal agencies focused on

research. They also know that finding employees with a strong capac-ity in math and science, and critical skills such as synthesis, analysis,teamwork, and presentation skills, helps productivity. Academics areimportant; applying them to real problems in a workplace settingmakes them valuable. Research experiences at corporate and federalfacilities, under the tutelage of seasoned scientists and engineers, givestudents an opportunity to exercise and hone their capabilities. Im-portantly, it also provides low risk opportunities to gain experience,find out likes and dislikes, and to understand the relevance of course-work. This makes the academic portion of the education more en-riching and exciting. Importantly, companies view internships as lowrisk opportunity as well. Students can work for a defined period oftime and the company can assess their motivation, skills, attitude, andpotential for a permanent fit within the corporation. Often these ex-periences can lead to permanent employment. This address will out-line some of the opportunities for research experiences in the U.S. De-partment of Energy National Laboratory’s, other federal agencies, andcorporations. It will also provide insights on how to secure a researchinternship opportunity - opportunities you will not want to miss.

4:20 PMSafe and Educational Materials Science DemosV. L. Knox*, L. M. Burka, PCSA, USA

Materials science is extremely important to engineering as it enablesother forms of engineering to succeed. Therefore, as Materials Scien-tists, we must continue to bring in future scientists through innova-tive ways of inspiring children and young adults. There are severalways to accomplish this goal; give educators tools for demonstrationshe can do in the classroom and give college students tools for demon-strations which they can take to their communities to not only getkids interested in science, but also to help promote enrollment attheir university. This section of the symposium will outline the cor-rect method of performing three simple demonstrations for bothchildren and young adults. The key idea is to make the demonstrationeducational by telling the students age-appropriate details about thescience at work and getting the students involved with the demon-stration by either getting dirty or smashing things to pieces. The threedemonstrations to be performed at the symposium are from the orig-inal Student Congress.

4:40 PMUndergraduate Research, at The Pennsylvania State University, onthe Nature of Iron-Nickel MeteoritesP. R. Howell*, J. Shubilla, L. Tran, J. Nunez, R. DeFrain, The PennsylvaniaState University, USA

The department of Materials Science and Engineering, in collabora-tion with the College of Earth and Mineral Sciences Museum has beenconducting a series of microstructural and microchemical studies onthe decomposition of austenite in a series of iron-nickel meteoritesfrom the museum collection. The studies have been conducted as partof the requirements of the senior thesis; our capstone engineering de-sign course. Meteorites studied include the Canyon Diablo and Hen-bury Irons, and a pallasite. We have employed a series of techniques forthe investigations, including scanning electron microscopy, ther elec-tron microprobe and orientation imaging microscopy. Topics coveredin the presentation will include the formation of Type I plessite in theHenbury meteorite, shock annealing in Canyon Diablo, and the forma-tion of Widmanstatten ferrite in the pallasite. All of the data will be in-terpreted in terms of the currently accepted iron-nickel phase diagram.

5:00 PMTool Collaborative for Management Solid Waste andEnvironmental SustainabilityM. S. Borges*, UFPR, Brazil

Automotive industries play an important role in the production anduse of goods and services. The management of solid waste is a chal-lenge for industrial parks, due to the large amount and variability

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 55

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania56

characteristics of the wastes from the production. The aim of this ar-ticle is analyze the implementation of a tool to improve the inventoryof industrial solid waste. The inventory is important for managementof industrial waste because to allow update and broaden the knowl-edge and characterization of different by-products. Through thattool is proposed to analyze the problem of industrial reject inside thesocio-environmental parameters seeking technical and economicfeasibility of their reuse. The implementation of this tool will allowthe identification, classification and quantification of byproducts forits reuse, taking into account that have been incorporated substancesof high commercial value and build up of raw materials that havelow cost.

Keynote & Lectures

Alpha Sigma Mu LectureRoom: 406

3:00 PMAn Update on the Development of a Hydrogen Economy:Opportunities for Materials Research (Invited)J. A. Spearot*, General Motors Research and Development Center, USA

Recent growth in developing global economies has raised significantquestions about the availability and social impacts of petroleum-based fuels for transportation applications. There are concerns re-garding the capability of petroleum-based fuels to meet the de-mands of global economic growth. In addition, greater use ofpetroleum-based fuels is expected to increase criteria emissions(HC, CO, and NOx) in urban environments and contribute togreater concentrations of carbon emissions in the atmosphere. De-veloping a more sustainable future transportation system will becritical to automotive manufacturers throughout the world. One op-tion that General Motors believes could contribute to a viable andsustainable transportation system is the development of renewablehydrogen/fuel cell propulsion technology. Such systems have beenunder intense development for the past ten years. This presentationdescribes some of the successes achieved to date and details the re-maining challenges that will be required to make hydrogen/fuel celltechnology a reality. Materials research will be critical in improvingthe durability and cost effectiveness of PEM fuel cells, the efficiencyof renewable hydrogen production technology, and the value and ca-pacity of hydrogen storage systems. Each of these issues is describedand opportunities identified for future material science researchprograms.

Electronic & Magnetic Materials: Copper andCopper Based Alloys in the ElectronicsIndustry

Copper and Copper Based Alloys in the ElectronicsIndustry IIRoom: 315Session Chair: Larry Wojnicz, Molex Incorporated

2:00 PMUnderstanding Stress Relaxation (Invited)S. J. Gross*, M. Bohsmann, Wieland-Werke AG, Germany

With increasing level of miniaturization as well the increasedusage of copper alloys for high temperature connector applications(e.g. under the hood applications in a car) the correct interpreta-tion of stress relaxation gets a key requirement to select the rightstrip alloy and temper. This article shall provide a deeper under-standing on how we can influence the stress relaxation behavior ina connector.

2:20 PMFatigue Behavior of Thin Cu Foils and Cu/Kapton Flexible CircuitsD. F. Beck, D. F. Susan*, R. Sorensen, G. E. Thayer, Sandia NationalLaboratories, USA

A series of thin electrodeposited Cu foils and Cu foil/Kapton flex cir-cuits were tested in bending fatigue according to ASTM E796 andIPC-TM-650. The fatigue behavior was analyzed in terms of strain vs.number of cycles to failure, using a Coffin-Manson approach. The ef-fects of Cu foil thickness and Cu trace width are discussed. The Cufoils performed as expected and the Cu foil/Kapton compositesshowed significant improvement in fatigue lifetime due to the com-posite strengthening effect of the Kapton layers. However, the flex cir-cuits showed more scatter in fatigue life based on electrical continu-ity. The effect of the Kapton layers manifests itself by significantlymore widespread microcracking in the Cu traces and the extent ofmicrocracking depended on the strain level. *Sandia is a multipro-gram laboratory operated by Sandia Corporation, a Lockheed MartinCompany, for the United States Department of Energy’s National Nu-clear Security Administration under contract DE-AC04-94AL85000.

2:40 PMThermal Conductivity of Copper/Silicon Carbide andCopper/Carbon Composites Derived from Wood PrecursorsK. Pappacena*, K. T. Faber, Northwestern University, USA; H. Wang, W.Porter, Oak Ridge National Laboratory, USA

Copper/silicon carbide and copper/carbon composites are of interestfor electronic heat sinks because they can have a desirable combina-tion of high thermal conductivity with low thermal expansion. Cop-per was infiltrated into the pores of biomorphic silicon carbide(bioSiC), a porous ceramic material derived from natural wood pre-cursors, as well as pyrolyzed wood, and commercial graphite foam.The thermal conductivity was tested up to 600°C. Object-oriented fi-nite-element analysis was used to model the thermal conductivityand provide insight into the heat flux through the complex pore dis-tributions in the wood derived carbon/copper and bioSiC/coppercomposites.

3:00 PMMicrostructure of a Cu-3%Ti alloy aged in a hydrogen atmosphereand its relation with electrical and mechanical propertiesS. Semboshi*, T. Nishida, Osaka Prefecture University, Japan; T. Al-Kassab,University Goettingen, Germany; H. Numakura, Osaka Prefecture University,Japan; R. Kirchheim, University Goettingen, Germany

It has recently been reported that aging of a Cu-3at.%Ti alloy in a hy-drogen atmosphere improves the electrical conductivity in compari-son to conventional aging in a vacuum [S. Semboshi and T. J. Konno, J.Mater. Res. 23 (2008) 473-477]. In the present work, we have investi-gated the evolution of the microstructure of the alloy by transmissionelectron microscopy and atom-probe tomography, together with thevariation of the conductivity and the mechanical strength. At an earlystage of aging in a hydrogen or deuterium atmosphere at temperaturesbetween 673 and 773 K, needle-shaped precipitates of Cu4Ti finelyform, and during subsequent aging cuboidal particles of delta tita-nium hydride begin to appear. The latter promotes reduction of the ti-tanium content in the solid-solution matrix, which leads to an im-proved electrical conductivity. At the same time, the yield strength andthe hardness of the alloys are also improved by the co-precipitation.

3:40 PMResidual Stresses in Cu-Be Strip: Measurement, Process-Sensitivity and Correlation to Performance (Invited)J. C. Harkness*, Brush Wellman Inc., USA

Residual stresses from non-uniform plastic deformation during Cu-alloy strip processing are frequently cited in the connector industry asa contributor to variable as-stamped part dimensions and/or co-pla-narity, as well as to large or unpredictable stamped part distortion

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 56

Mo

nd

ay P

M

www.matscitech.org 57

during final precipitation hardening. To attempt to verify these asser-tions, residual stresses in UNS C17200 and C17460 Cu-Be alloy stripwere studied via quantitative measurement by X-ray diffraction andqualitative assessment by wire-EDM finger test as well as by etchingto half thickness. Effects on residual stress profiles of cold rolling,thermal treatment and mechanical stress reduction by Tension Level-ing or Stretch Bend Leveling were evaluated. Dimensional variationand aging distortion were measured in C17200 strip for comparisonto known residual stress distribution.

4:20 PMCantilever Beam Bending Strength Enhancement through theApplication of Reverse Bending and Relief Annealing/AnnealHardening Techniques (Invited)J. Stainbrook*, L. Wojnicz, C. Manlapaz, A. Coughlin, Molex Incorporated, USA

Certain electronic connector applications require a low profile contactbeam capable of applying sufficient normal force to the contact inter-face. This can be conveniently accomplished with a small upward bendon the material, therefore forming a low angle cantilever beam. Subse-quently when mated, a load pushing opposite to the cantilever’s formingdirection will generate a normal force that varies as a function of beamdeflection distance. Unfortunately, when applying force opposite to theforming direction, the Bauschinger effect is encountered and the beamtakes a premature plastic set. Certain techniques may be deployed topartially or wholly off-set this Bauschinger effect, producing the desiredmechanical strength level and performance. This work will discuss thetechniques of reverse bending and stress relief anneal / anneal hardeningand will demonstrate their effects when applied to cantilever beams.

Electronic & Magnetic Materials:Ferroelectrics and Multiferroics

Domain Switching, Phase Transition Behavior,Texturing, and Lead-free PiezoelectricsRoom: 318Session Chairs: Paul Clem, Sandia National Laboratories; DwightViehland, Virginia Tech

2:00 PMDomain Microstructures and Mechanisms for EnhancedPiezoelectricity in Morphotropic Phase Boundary Ferroelectrics(Invited)W. Rao, Y. U. Wang*, Virginia Tech, USA

Phase field model is employed to study some underlying mechanismsresponsible for the enhanced electromechanical properties near themorphotropic phase boundaries (MPBs) in ferroelectric solid solu-tions. This talk will present some new insights gained into the phase-coexisting domain microstructures and field-induced inter-ferroelec-tric phase transformations and their relations to the advancedpiezoelectric behaviors around MPB. The new findings include domainwall broadening mechanism for domain size effect of enhanced piezo-electricity, bridging domain mechanism for phase coexistence, ferro-electric shape memory effect, grain size effect of phase coexistence,nanodomain microstructures of coherent ferroelectric phase decom-position, and adaptive diffraction phenomenon peculiar to nan-odomain microstructures. Physical implications of the gained under-standing to other ferroic and multiferroic materials are also discussed.

2:40 PMNanoscale Structural Instabilities in Morphotropic FerroelectricSolid SolutionsG. A. Rossetti*, University of Connecticut, USA; A. G. Khachaturyan, Rutgers,The State University of New Jersey, USA; D. D. Viehland, Virginia PolytechnicInstitute and State University, USA

This talk reviews the formation, crystallography, and physical proper-ties of ‘adaptive’ nano-domain states in ferroelectric solid solutions.

These adaptive states form near morphotropic boundaries due to adrastic lowering of the polarization anisotropy energy and impartunique properties that include (i) stringent relations among the crys-tal lattice parameters that are invariant to changes in temperature,composition or applied fields, (ii) strong extrinsic softening of theelastic, piezoelectric and dielectric compliances, and (iii) special rela-tions among the components of the piezoelectric and dielectric ten-sors. The formation of adaptive states having nano-domain wallswith rotational structure resolves inherent contradictions betweenthe thermodynamic conditions required to stabilize low-symmetryferroelectric phases and the continuous orientation change of the po-larization vector producing large electromechanical property re-sponses as observed near morphotropic phase boundaries.

3:00 PMSurface effect on domain wall broadening and threshold coercivefield of LiNbO3 and LiTaO3 free-standing filmsY. Li*, L. Chen, V. Gopalan, Pennsylvania State University, USA; J. Shen,Purdue University, USA; Q. Jia, Los Alamos National Laboratory, USA; A. N.Morozovska, E. A. Eliseev, National Academy of Science of Ukraine, Ukraine;S. V. Kalinin, Oak Ridge National Laboratory, USA

We study the surface effect on the ferroelectric polarization profileand the 180 degree domain wall width by phase field modeling. Thecontributions of depolarization field and finite extrapolation lengthare taken into account. It is found that the polarization profile nearthe mechanical stress-free surface has a dramatic change with the fi-nite extrapolation length. Positive extrapolation length broadens the180 degree domain wall close to the surface. Scanning probe mi-croscopy shows evidence for such broadening in LiNbO3 and LiTaO3free-standing films. Simulations also show that the threshold coercivefield for moving this wall dramatically drops by 2-3 orders of magni-tude if the wall were diffuse by only ~2-3nm.

3:40 PMDevelopment of novel piezoceramics through textured ceramicmicrostructuresC. DiAntonio*, M. Winter, M. Rodriguez, P. Yang, T. Chavez, G. Burns, SandiaNational Laboratories, USA

The development of an advanced process that results in a texturedpolycrystalline material with improved properties in comparison toits random polycrystalline counterpart is the prevailing target of thisresearch. Molten salt synthesis, coupled with shear induced orienta-tion, has provided preferential crystallographic alignment to producea textured bulk ceramic. The test vehicles to demonstrate this are thebismuth-layer structured ferroelectric compound bismuth titanate,Bi4Ti3O12, and Na0.50Bi0.50TiO3. The degree of texture develop-ment has been evaluated during the process based on the microstruc-ture and in terms of x-ray diffraction analysis. The ferroelectric prop-erties have been gauged by impedance analysis and electromechanicalbehavior and compared to random polycrystalline microstructures.The synthesis and fabrication technique will be discussed, includingdetails of the templating, texturing, and forming processes, that resultin enhanced functional ceramic components.

4:00 PMOrientation of KNLN-BT Ceramics by TGG MethodC. Ahn*, M. Karmarkar, Virginia Tech, USA; S. Nahm, Korea University,South Korea; S. Priya, Virginia Tech, USA

Templated Grain Growth (TGG) of (1-y)(K0.5-xNa0.5-xLix)NbO3-yBaTiO3 (KNLN-BT) system which is an Pb-free piezoelectric mate-rial is investigated in this work. Initially, the variations of crystalstructure and microstructure were studied to find morphotropicphase boundary (MPB) in KNLN-BT ceramics. In addition, TGGmethod was used for the orientation of KNLN-BT ceramics which layon MPB region. The crystal structure and microstructure of the spec-imen prepared with TGG method were studied and the effect of theorientation on piezoelectric properties was introduced in this report.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 57

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania58

4:20 PMPatterned Microstructures in Polycrystalline BaTiO3M. Ugorek*, G. Messing, S. Trolier-McKinstry, Pennsylvania StateUniverstiy, USA

An understanding of microstructure evolution in ceramic materials,including texture development and enhanced grain growth should en-able more controlled final structures. In this study, photolithographywas used to pattern dopant, (001) and (110) BaTiO3 single crystal tem-plate arrays with varying sizes, shapes and spacings. These patternswere subsequently used to control the matrix grain growth evolutionand texture development in BaTiO3. We show that the growth kineticsare enhanced and can be controlled by a small initial grain size, atmos-phere conditions and the introduction of a liquid phase at selective in-terfaces. By using a PO2 of 1x10-5 atm during high temperature heattreatment, the matrix coarsening has been limited (to roughly 2x theinitial grain size), while retaining single crystal boundary motion up to0.5 mm during growth for dwell times up to 10 hr at 1300oC.We will re-port on the longitudinal and lateral growth rates observed under differ-ent oxygen partial pressures and patterned microstructures obtained.

4:40 PMTexturing to Realize Improved Properties in Lead-Free MaterialsUsing Scalable Processing TechniquesM. R. Winter*, C. B. DiAntonio, T. Chavez, R. Mark, Sandia National Labs, USA

Increasing concern surrounding lead use in consumer products hasstimulated research to replace lead-based materials in many applica-tions. To be commercially viable, a lead-free replacement must be fab-ricated using cost-effective industrial techniques while maintainingexcellent dielectric properties. Texturing can dramatically enhancethe dielectric properties of lead-free materials such that several po-tential systems are now being considered as replacements for the cur-rent lead-based materials. Layer-structured perovskites offer a richvariety of alternatives, particularly the bismuth layered and alkali nio-bate-based solid solution ferroelectrics. In this work, highly texturedbulk samples have been produced through the process of screenprinting large, plate-like seeds in a matrix of equi-axial powder. Thetexturing achieved gives rise to the potential for excellent dielectricproperties, making textured materials a viable replacement for com-mercial lead-based dielectrics.

Electronic & Magnetic Materials:International Symposium on AdvancedDielectric Materials & Electronic Devices

Composition, Processsing, Microstructure, andProperty Relationships IIRoom: 317Session Chair: Amar Bhalla, Pennsylvania State University

2:00 PMProcessing of High-K Dielectrics: Ball milling, contamination,microstructure and properties (Invited)T. Brommer, S. Stuckenholz, D. Payne*, University of Illinois at Urbana-Champaign, USA

The design of a K6000 formulation in the barium titanate -calciumzirconate -strontium titanate system is described. Data are given forthe effect of compositional changes on K-T characteristics, peak shift-ing and broadening, temperature coefficients of K, XRD and latticeparameters of solid solutions, SEM of microstructures, and refine-ment through magnesium titanate additions. In particular, the effectof ball milling on changes in K-T characteristics, and correlations ofcontamination content with changes in phase content, microstruc-ture and properties. The deleterious effect of milling with aluminamedia is compared with zirconia media, and purposeful additions ofalumina and zirconia. The K-T results are discussed in terms of

changes in phase content and microstructure with unintentionalchanges in composition by ball milling.

2:40 PMLow Temperature Sintering of BaTiO3 without Grain Growth viathe addition of Mn-Si-O GlassC. Lin*, W. Wei, Ceramics processing and analysis Lab, Taiwan; A. Roosen,Glass and Ceramics institute, Germany

A binary glassy system (Mn2O3-SiO2) was investigated from two sam-ples sets. One is a sandwich of the glass between BaTiO3 (BT) disks.The softening point, wetting behavior, crystallization, compositionalevolution of the Mn-Si-O glass due to the dissolution of BaTiO3 werestudied. The other is powder mixture with glass power. The BT parti-cles in size of ~0.4 μm were fully sintered by the glass in 1.0 wt% at1125oC for 1 hr. The average grain size of the sintered BT is nearly con-stant, 500 nm, as sintered between 1125-1275oC/1 hr or at 1250oC for1-27 hr. TEM images exhibit BT grains next to glassy pockets in a com-position of Ba-Ti-Si-O. Scanning TEM with EDS showed no Si or Mnin the BT grains. Quantitative XRD results showed the change of tetrag-onality of BT, which probably resulted from the solid solution of Mnion. The effects of the glass quantity on microstructures and electricproperties have been examined and will be presented in this reported.

3:00 PMEffects of acceptor impurities on capacitance aging behavior ofBaTiO3 under DC electric fieldsD. Hahn*, Sungkyunkwan University, South Korea; S. Sohn, Samsung Electro-Mechanics, South Korea; Y. Han, Sungkyunkwan University, South Korea

Capacitance aging behavior of BaTiO3 based dielectric materialsunder DC electric fields has been studied. When the DC electric fieldwas applied, an immediate drop in capacitance occurred within 10seconds (the first stage) and then capacitance of the specimens de-creased gradually with time (the second stage). Doping of manganeseoxide led to higher DC bias aging rates compared with the undopedBaTiO3. The total capacitance change under DC electric field de-creased significantly with the addition of MgO or rare earth oxides.The addition of acceptor impurities with invariable valence state effec-tively suppressed the capacitance aging behavior of Mn doped BaTiO3.However, the addition of MnO is essential to lower the insulating re-sistance (IR) degradation of BaTiO3 based dielectric materials. Thus,the balanced addition of MnO and acceptor impurities is required tosatisfy the DC bias capacitance aging as well as IR degradation.

3:40 PMEffect of rare earth elements doping on the electric properties of(Ba,Sr)TiO3 thin film capacitors (Invited)N. Kamehara*, K. Kurihara, FUJITSU QUALITY LABoratory LTD., Japan

Barium strontium titanate (BST) thin film capacitors are being inten-sively investigated for tunable microwave devices, because of their highpermittivity, low dielectric loss in the microwave region and field de-pendent permittivity. This study investigates the effect of rare earth ele-ments doping on the electrical properties of BST thin film capacitors.BST thin films were deposited by an RF magnetron sputtering techniqueon Si wafers. BST films were prepared with Y concentration of 0-5%.Lattice parameters were measured using synchrotron radiation X-rayanalysis. The results show that Y doped BST capacitors exhibit not onlysignificantly higher permittivity but also low leakage current density ascompared to nominally undoped BST capacitors. X-ray diffraction re-sults show the film strain state strongly depends on film compositionand dopants with tunability decreasing with increasing tensile strain.

4:00 PMStructure-Property Relationships of Epitaxial Ferroelectric ThinFilms (Invited)X. Pan*, University of Michigan, USA

Recent studies have shown that epitaxial strain can drastically affectferroelectric properties (transition temperature and polarization) in

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 58

Mo

nd

ay P

M

www.matscitech.org 59

BaTiO3 thin films and produce room-temperature ferroelectricity inSrTiO3. Atomic resolution transmission electron microscopy analysisof strained BaTiO3 predicts the enhancement of spontaneous polar-ization by more than 100%. This talk will focus on the structure-prop-erty relationships of such epitaxial ferroelectric thin films and multi-layers. The effect of lattice mismatch (epitaxial strain), crystal defects,and chemistry at the film/substrate interfaces on the microstructureand physical properties of different systems will be addressed.

4:20 PMGrowth of Epitaxial Bi-Zn-Nb-O Pyrochlore Thin films onEpitaxial Pyrochlore Bottom Electrode and Their ElectricalProperties (Invited)H. Funakubo*, R. Ikariyama, S. Yausui, T. Yamada, Tokyo Institute ofTechnology, Japan; K. Saito, H. Morioka, Bruker AXS, Japan; T. Kaneko, Y.Kobayashi, K. Asai, The University of Electro-Communications, Japan

Epitaxial pylochlore (Bi1.5Zn0.5)(Zn0.5Nb1.5)O7 [BZN] thin filmshave been widely investigated. To get more enhanced properties, thedevelopment of the epitaxial bottom electrode having epitaxial rela-tionships with BZN film, pyrochlore bottom electrode, is highly re-quired as same as perovskite dielectrics. In the present study,Bi2Ru2O7 films were successfully grown on (111)YSZ-coated Si sub-strates by MOCVD. Wide process window of the film compositionwas ascertained for the input ratio of Bi and Ru sources in MOCVDprocess. Good crystallinity of Bi2Ru2O7 compatible to that of theunderlying YSZ layers was ascertained by XRD analysis and its roomtemperature resistivity was on the same order of the reported one forthe single crystal. In addition, epitaxial films of pyrochlore dielectrics,(Bi1.5Zn0.5)(Zn0.5Nb1.5)O7, was ascertained to be successfullygrown on epitaxial Bi2Ru2O7 layers.

4:40 PMThe Effect of Microstructure on the Ferroelectric Switching ofPolycrystalline Ferroelectric Films (Invited)R. Garcia*, J. E. Blendell, K. Bowman, Purdue University, USA

Ferroelectric PZT films display physical behavior that makes them animportant candidate for random access memories. In such devices,ferroelectric domains are locally switched by the application of anelectric field, thus fixating the state of a memory unit. Today’s techno-logical advancement demands ever higher memory densities. There-fore, as the device size shrinks, the microstructural features becomeincreasingly important. Simulations show that in-plane electro-mechanical interactions electrically shield some of the grains, whileenhancing the polarization response in others. Additionally, graincorners and boundaries become domain nucleation sites as well asdomain pinning locations. The local phenomenology observed inthese simulations agrees macroscopically with the observed experi-mental behavior and is used as a basis to propose microstructuralmechanisms that explain the local in-plane and out-of-plane ferro-electric switching behavior.

5:00 PMComposition, Cation ordering, Conductivity and Dielectric LossRelationships in BaCo1/3Nb2/3O3 Microwave Dielectric CeramicsM. Li*, A. Feteira, D. C. Sinclair, The University of Sheffield, United Kingdom

The effect of sintering atmosphere, cooling rate and post annealing inN2 on the composition, cation ordering, conductivity and dielectricloss of BaCo1/3Nb2/3O3 (BCN) ceramics have been investigated. XRD,TEM and Raman results confirm that a slow cooling rate and/or postannealing increase the degree of B-site cation 1:2 ordering regardlessof the sintering atmosphere. Qf, however, is found to be strongly de-pendent on sintering atmosphere. Samples sintered in O2 exhibitmuch lower Qf than those sintered in air despite their similar degreeof 1:2 ordering. Post annealing in N2 reduces Qf although the degreeof 1:2 ordering is increased. Impedance Spectroscopy results showthat conductivity increases with PO2 for samples sintered in O2 andair, while samples annealed in N2 are electrically heterogeneous.

These results show that Qf is heavily influenced by conductivity inBCN ceramics and there is no evidence of a link between Qf andcation ordering.

Electronic & Magnetic Materials: Pb-Free, Pb-Bearing Joining and Packaging Materials andProcesses for Microelectronics

Materials and Processes for Advanced PackagesRoom: 319Session Chairs: Eric Cotts, Binghamton University; Sinn-wen Chen,National Tsing Hua University

2:00 PMSolidification of Sn-Bi-Ag and Sn-Bi-Ni alloys (Invited)S. Chen*, Y. Chen, H. Wu, Y. Huang, National Tsing Hua University, Taiwan

Sn-Bi alloys are important Pb-free solders. Ag and Ni layers are com-monly encountered in the electronic products. With the dissolutionof Ag and Ni into the molten solders during reflow, the binary Sn-Bialloys become ternary Sn-Bi-Ag and Sn-Bi-Ni. Isothermal sections at300oC and liquidus projections of the Sn-Bi-Ag and Sn-Bi-Ni sys-tems were determined. Their heating and cooling curves were deter-mined using Differential Thermal Analysis and Differential ScanningCalorimetry. The phases formed during solidification were deter-mined using Scanning Electron Microscopy, X-ray diffraction andElectron Probe Microanalysis. Solidification paths of the Sn-Bi-Agand Sn-Bi-Ni alloys were determined based on the liquidus projec-tion, phase formation and results of thermal analysis. It is found thatthe solidification path follow that mono-variant line up to the pointwhere the corresponding tie-triangle moves with one edge out of thealloy composition, then the liquid composition will leave the mono-variant line.

2:40 PMLow-Temperature Reduction of Ag2O Particles Utilizing LongChain Alcohol -Novel Bonding Process Using Ag2O Particles(1streport)-Y. Yasuda*, Hitachi, Ltd. Materials Research Laboratory, Japan; M. Tobita,Hitachi, Ltd. Advanced Research Laboratory, Japan; E. Ide, T. Morita, Hitachi,Ltd. Materials Research Laboratory, Japan

We developed a novel bonding technique for semi-conductor devicepackaging applied in high-temperature environments, utilizing Ag2Oparticles with myristyl alcohol as a bonding material. Thermal reductionof Ag2O particles is known to occur at a temperature over ca.660K. In thisstudy, the mechanism of the thermal reduction and sintering of Ag2Oparticles with myristyl alcohol were studied. The reduction was found tooccur at 410-440K even when the amount of myristyl alcohol was con-siderably smaller than that needed for promoting alcohol reduction. AnExcess amount of heat,which was measured to be 135kJ/mol,used for theAg2O reduction was produced by oxidation of myristyl alcohol. A pair ofsilver substrate was bonded with the developed material at bonding tem-perature of 523K. The bonding strength of 10MPa was achieved. Thisbonding is stronger than that formed by conventional Ag nanoparticles.

3:00 PMIn-situ Formation of Ag Nanoparticles and Bonding Mechanismon Au Substrate -Novel Bonding Process Using Ag2O Particles(2nd Report)-H. Tatsumi*, N. Takeda, Y. Akada, Graduate School of Engineering, OsakaUniversity, Japan; T. Morita, E. Ide, Hitachi, Ltd., Japan; A. Hirose, GraduateSchool of Engineering, Osaka University, Japan

We developed a new bonding process using Ag2O particles for hightemperature electronic applications. In the present study, the forma-tion process of Ag nanoparticles and the interfacial bonding mecha-nism between Ag layer with sintered Ag nanoparticles and Au sub-strate were discussed. It was confirmed that Ag nanoparticles forms at

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 59

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania60

403K to 433K through the decomposition process of Ag2O particlesby a thermal analysis. The Ag nanoparticles are immediately sintereddue to the great surface energy. The HRTEM observation revealedthat a sintered Ag and Au substrate are metallurgically bonded at theinterface between a nanometer-scale Ag layer and Au substrate at433K. In addition, the obtained higher strength and electrical resistiv-ity of the specimens using this process proves the effectiveness ofAg2O as a new bonding material.

3:40 PMEvaluation of Bonding Characteristics of Cu/Au-to-Cu/Au jointsusing Ag2O Particles -Novel Bonding Process using Ag2O Particles(3rd Report)-N. Takeda*, H. Tatsumi, Y. Akada, A. Hirose, Graduate School of Engineering,Osaka University , Japan; T. Morita, E. Ide, Materials Reseach Laboratory,Hitachi, Ltd., Japan

We have proposed a novel bonding process using Ag2O particles,which forms Ag nanoparticles in decomposition, as a new Pb-free al-ternative with high melting point. In the present study, it was revealedthat the shear strength of Cu/Au-to-Cu/Au joint using Ag2O particlesis higher than that using Ag metallo-organic nanoparticles(averageparticle size : 20nm), Ag fine particles(190nm) and a conventionalPb-5Sn solder. To clarify the high strengthness of the bonding jointusing Ag2O, FE-SEM and TEM observation were performed. TheAg2O-derived Ag nanoparticles can be sintered uniformly no higherthan 523K owing to no stable organic remnant which inhibits sinter-ing of nanoparticles. Moreover, the dense sintered Ag layer with Agnanoparticles is metallurgically bonded to Au substrate, indicatingthat Ag nanoparticles have high sintering performance.

4:00 PMEffects of Thermal Input on the Mechanical Properties ofComposite Solder Joint via Morphological Changes inReinforcement ParticulatesL. Ma*, W. Zhang, J. Nie, F. Guo, Beijing University of Technology, China

Thermal input is an important factor that determines the formationof different IMC morphologies and consequently affecting the me-chanical properties of the composite solder joints. The IMC layersaround Ni particles were observed to transform from sunflowershape into blocky faceted shape with increasing thermal input. Thecurrent research quantitatively evaluates the effects of different ther-mal input values on the morphologies of IMCs around the Ni rein-forcement particles. The simple shear tests were conducted on solderjoints containing reinforcement particles with sunflower, blocky, andmixed morphologies. As a comparison and verification, a mi-crostructure based finite element analysis was used to model thestress and strain distribution in the solder joints under different pro-cessing conditions.

4:20 PMWetting behavior between lead-free solders and bulk metallicglassesH. Nishikawa*, K. WongPiromsarn, H. Abe, T. Takemoto, Osaka University,Japan; M. Fukuhara, T. Wada, A. Inoue, Tohoku University, Japan

In order to adopt bulk metallic glasses in a broader range of engineer-ing applications, it is very important to establish appropriate joiningprocesses of bulk metallic glasses. During the joint of bulk metallicglass, the most serious issue is the reformation of glassy phase at thehigh temperature area. Therefore, to avoid the recrystallization ofglassy phase, soldering process has been tested to join metallic glasses.In this study, the spread test of lead free solders was mainly per-formed at 523 K for 60s. Results showed that lead-free solders werespread on only Pd-based metallic glass and Sn-3.0Ag-0.5Cu had bet-ter wetting characteristics comparing with Sn-57Bi and Sn-51In. Themicrostructure at the interface between Sn-Ag-Cu and Pd-basedmetallic glass was analyzed by scanning electron microscopy. It was

clear that the intermetallic compound, PdSn4 phase, was formed atthe interface.

Electronic & Magnetic Materials: PerovskiteOxides: Films, Nanostructures, Properties,and Applications

Perovskite Oxide Films and Nanostructures IIRoom: 316Session Chairs: Carolina Adamo, Pennsylvania State University;Chong-Lin Chen, University of Texas, Austin

2:00 PMElectrical and magnetic properties of epitaxial (SrMnO3)n/(LaMnO3)2 superlattices (Invited)C. Adamo*, X. Ke, P. Schiffer, A. Soukiassian, M. Warusawithana, Penn StateUniversity, USA; L. Maritato, Dipartimento di Matematica, Italy; D. Schlom,Penn State University, USA

A variety of interesting and unexpected electronic and magnetic phe-nomena have been observed at the interfaces between different oxidesand the role of charge transfer across those interfaces has been ac-tively studied in recent years.[1,2]In this context,(SrMnO3)n/(LaMnO3)2n superlattices, consisting of n planes ofSrMnO3 alternating with 2n planes of LaMnO3, show a remarkableinterfacial modification of the bulk properties of the two constituentmaterials. For example, although both SrMnO3 and LaMnO3 are an-tiferromagnetic insulators in bulk, SrMnO3/LaMnO3 superlatticescan be ferromagnetic and metallic. Dynamical mean field theory cal-culations have suggested that the metallic behavior originates from anelectronic reconstruction at the interface and that the charge transfereffects extend deeply in the layers away from the interfaces, thus lead-ing to unique electronic and magnetic properties of the superlatticesas a whole.

2:40 PMA Transmission Electron Microscopy Investigation of the StructureLayered Perovskite Compounds in RE2Ti2O7 (RE = Sm, Gd)S. Wang*, S. Havelia, K. Balasubramaniam, M. De Graef, P. Salvador, CarnegieMellon University, USA

Epitaxial thin films of RE2Ti2O7 compounds (RE = Sm and Gd)were deposited on single crystal SrTiO3(110) substrates using pulsedlaser deposition. Although the stable bulk compounds adopt a py-rochlore structure, two distinct metastable perovskite-related poly-morphs were produced as epitaxial thin films by controlling the dep-osition parameters. One polymorph is isostructural to the (110)layered perovskite structure of the ferroelectric La2Ti2O7; their mon-oclinic crystal structure was confirmed using electron microscopymethods.The second polymorph has no bulk analogue, although wedemonstrate that it is related to the layered perovskite and that itforms an epitaxial film on the (110) SrTiO3 substrate. Selected areadiffraction, high-resolution imaging, and convergent-beam electrondiffraction techniques were used to unravel the differences betweenthe two structures and to determine the structure of the unknownpolymorph.

3:00 PMMicrostructure Properties of Vertically-Aligned Nanocomposite(BiFeO3)x:(Sm2O3)1-x Thin Films Deposited by Pulsed LaserDepositionZ. Bi*, J. Lee, Texas A&M University, USA; J. L. MacManus-Driscoll,University of Cambridge, United Kingdom; Q. Jia, Los Alamos NationalLaboratory, USA; H. Wang, Texas A&M University, USA

Epitaxial vertically-aligned nanocomposite (VAN)(BiFeO3)x:(Sm2O3)1-x thin films were deposited on SrTiO3 (001)substrates by pulsed laser deposition technique (PLD). The VAN

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 60

Mo

nd

ay P

M

www.matscitech.org 61

thin films exhibit a highly aligned vertical columnar structure withhigh epitaxial quality. The composition of the nanocomposites (x)was varied from 0.5 to 1. The deposition temperature and deposi-tion frequency were systematically varied from 500oC to 750oCand from 1 Hz to 10 Hz, respectively, to explore the microstruc-tural variation as functions of the growth parameters. The filmswere characterized by cross-section transmission electron mi-croscopy (TEM), scanning transmission electron microscopy(STEM), Energy dispersive spectroscopy (EDX, in TEM column)and X-ray diffraction (XRD). The detailed microstructural analysisrevealed that the VAN structures are highly dependent on the dep-osition temperature, deposition frequency as well as the film com-position (x).

3:40 PMEpitaxial Piezoelectric Thin Films on Flexible Substrates (Invited)C. Shelton, Oregon State University, USA; V. Matias, Los Alamos NationalLaboratory, USA; B. J. Gibbons*, Oregon State University, USA

It is known that the piezoelectric properties of a material can be in-fluenced by crystallographic texture. {100}-PZT films show a signifi-cantly larger transverse piezoelectric response than {111}-orientedfilms. At the extreme, epitaxial films can be deposited on single crys-tal substrates to achieve a single crystal film where the maximum ad-vantage of orientation dependence is found. To now this has requiredexpensive single crystalline substrates. Recently the technique of IonBeam Assisted Deposition has been developed for applying a biaxialtextured template to an arbitrary surface: this has opened up a newrealm of materials integration possibilities. Here, this template is uti-lized for deposition of epitaxial PZT thin films onto flexible sub-strates. PZT films with in-plane FWHM values of ~ 4° and out-of-plane FWHM ~ 1.4° have been deposited on flexible material. Theyshow a fine grained structure with square hysteresis loops having ~34μC/cm2 Pr. Piezoelectric data on varying compositions of PZT will bereported.

4:20 PMEpitaxial growth of perovskite-related stable and metastablecompounds in the RE2Ti2O7 familyS. Havelia*, S. Wang, B. Kavaipatti, P. Salvador, Carnegie Mellon University, USA

The RE2Ti2O7 family of compounds exhibit interesting properties;ferroelectricity in the (110) layered perovskite structure (RE = La-Nd) and oxide ion conduction in the pyrochlore structure (RE = Sm-Lu). Extension of the polymorph boundary through normal ceramicsynthesis of metastable compounds in this family is difficult. We in-vestigated the phase competition between the known stable andmetastable phases of these compounds during epitaxial growth viaPLD. Epitaxial RE2Ti2O7 thin films, in the (110) layered perovskitestructure for RE = La-Dy on SrTiO3 (110), and pyrochlore structurefor RE = Dy-Nd on YSZ(111) substrates were realized. The lattice pa-rameters follow a uniform trend, increasing with the size of the rareearth cation. Interestingly, a (110) layered perovskite-related poly-morph, unknown in bulk systems, was obtained for all RE cations.The structure of the two layered perovskite polymorphs and effect ofgrowth parameters on polymorph stability will also be discussed.

4:40 PMStrain and interfacial effects in perovskite heterostructures(Invited)H. M. Christen*, D. Kim, C. Callender, H. Lee, M. D. Biegalski, C. M. Rouleau,Oak Ridge National Laboratory, USA

Epitaxial films and superlattices are ideal for the study of epitaxialstrain and interfacial coupling between dissimilar perovskites.Pulsed-laser deposition (PLD) can be used to synthesize the re-quired heterostructures. PLD also allows us to synthesize alloys,such as those between ferroelectric BiFeO3 and antiferroelectricBiCrO3, in which we observe a surprising stability of the ferroelec-

tric polarization. Similarly, the polarization in BiFeO3 is surpris-ingly strain-independent, as in the case of PZT, but contrary toKNbO3 or BaTiO3. Here, artificial superlattices allow us to separatethe effects of strain, interfaces, and long-range interactions. Thisshows that interfaces generally have a detrimental effect on most fer-roelectric properties. A different situation arises at interfaces withchanges in the electronic configuration: in LaMnO3/SrTiO3 super-lattices, electronic effects produce interfacial ferromagnetism. Spon-sored by Div. of Mat. Sci. and Eng. and Div. of Sci. User Facilities,BES, US-DOE.

Environmental & Energy Issues: Ceramicsand Glass for Waste Minimization,Stabilization, and Disposition

Low Temperature Waste Form Development andTestingRoom: 326Session Chair: Alex Cozzi, Savannah River National Lab

2:00 PMMeasuring permeability of cementitious materials (Invited)Z. C. Grasley*, Texas A&M Univ., USA

The performance of a cementitious material is often dictated by theability of the material to resist physical and chemical transportthrough its pore network. Permeation associated with a pore pres-sure gradient and diffusion associated with a concentration gradientare inter-related mechanisms which may each contribute to overallmass transport. Permeability is often chosen as a means to quantifythe resistance to transport through a cementitious material. Unfortu-nately, there are several reasons why permeability is a difficult pa-rameter to accurately measure; these issues will be discussed alongwith a review of traditional permeability measurement techniques.In addition, recently developed poromechanical permeability meas-urement techniques will be discussed along with their potential forfuture use in industry, including the waste management and contain-ment industry.

2:40 PMDevelopment and Testing of Grouts for Stabilization of High-LevelWaste Tank Cooling CoilsE. Hansen*, J. Harbour, Savannah River National Lab, USA; J. Harden,Clemson Environmental Technology Laboratory, USA

The current concept for closing high-level waste (HLW) tanks atthe Savannah River Site equipped with cooling coils is to pumpgrout into the coils to prevent pathways for infiltrating water.Laboratory studies involved grout development and testing. Agrout formulation suitable for filling HLW tank cooling coils wasdeveloped and tested. Rheology of the cooling coil grout wascharacterized to support the demonstration. A placement demon-stration under simulated field conditions was performed to rec-ommend production and pumping conditions for the filling oftank cooling coils.

3:00 PMReactivity of crystalline and amorphous phases in fly ashR. Chancey, Nelson Architectural Engineers, Inc., USA; M. Juenger*, TheUniversity of Texas at Austin, USA

Most fly ash reactivity investigations only consider the bulk reactivityof the ash because of incomplete information on the constituentphases. In this study, a Class F fly ash was examined using Rietveldquantitative x-ray diffraction (RQXRD) and scanning electron mi-croscopy coupled with multispectral image analysis (SEM-MSIA) tocompletely and quantitatively characterize its crystalline and glassy

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 61

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania62

phases. The fly ash was then combined with a variety of solutions, in-cluding water, concrete pore solution, and a sodium hydroxide solu-tion to examine its reactivity over time. Subsequent RQXRD, SEM-MSIA, mass loss, and solution analysis revealed the reactivity of theindividual phases in these solutions.

3:40 PMFormulation and Confirmation Testing for Saltstone forStreamlined OperationsA. Cozzi*, E. Hansen, Savannah River National Lab, USA; A. Staub,Washington Savannah River Company, USA

The Savannah River Site Saltstone Production Facility (SPF) solidifiesradioactive salt waste into a grout waste form. Historically, the for-mulation for operation of the SPF was performed in the facility labo-ratory with a sample from the facility feed tank. The recent facilityupgrades to process salt solutions containing increased radionuclidecontent from the Deliquify, dissolve, and Adjust (DDA) campaign re-quire that the formulation work take place in shielded cells. The Sa-vannah River National Laboratory blended samples from the individ-ual waste tanks to simulate the tank transfers used to make the DDAsalt batch. A Saltstone grout formulation was developed using thissalt solution for start of of the SPF. A sample of the completed saltbatch was obtained and analyzed and the production formulationwas verified.

4:00 PMStudy of the sodalite phase for the conditioning of contaminatedNaCl saltI. Bardez*, D. Rigaud, M. Chartier, CEA, France

Sodalite Na8Al6Si6O24Cl2 was investigated for the conditioning ofNaCl salt arising from spent nuclear fuel reprocessing by a pyro-chemical process. Because of the tendency of halides to volatilize athigh temperature, two synthesis routes were tested to optimize thechloride content in the sodalite phase. The first is based on heatingat high temperature of a [nepheline NaAlSiO4 + salt] mixture pre-pared by a dry process. The second, performed at low temperature,consists of the reaction in aqueous media between kaolinite(Al2Si2O5(OH)4), sodium hydroxide (NaOH) and the salt. Thepresent study compares these two syntheses on the basis of X raydiffraction and infrared spectroscopy. The first results show thatthe chlorosodalite phase obtained by dry process is quite stoechio-metric whereas a slight competition was detected between chlorideions and hydroxyls or carbonates during the wet synthesis. The nextstep will consist in sintering the resulting powders to obtain denseceramics.

4:20 PMElectromotive Force Series of Redox Couples in Model FluidizedBed Steam Reforming SystemsH. D. Schreiber*, K. M. Mayhew, A. M. Swink, Virginia Military Institute, USA

Fluidized Bed Steam Reforming (FBSR) is a technology that showspromise for processing certain low-activity nuclear waste streams.The process employs a temperature low enough to retain the ra-dionuclides but high enough to destroy organic compounds. To amodel FBSR composition was added certain multivalent elements tomeasure their redox properties as a function of processing tempera-ture and atmosphere. An EMF (electromotive force) series was thenexperimentally determined for select redox couples in this referencecomposition under static anhydrous conditions as well as under dy-namic simulations employing gaseous carbon monoxide and water inthe presence of graphite. In order of relative reduction potentials:Mn(III)-Mn(II) > Ce(IV)-Ce(III) > Cr(VI)-Cr(III) > V(V)-V(IV) >Fe(III)-Fe(II) > S(VI)-S(-2) > U(VI)-U(V)-U(IV) > Pb(II)-Pb(0) >Ni(II)-Ni(0) > Re(VII)-Re(IV) > Eu(III)-Eu(II) > Ti(IV)-Ti(III) atreference FBSR conditions of the C/CO buffer.

Environmental & Energy Issues: EnergyMaterials

Characterization TechniquesRoom: 327Session Chairs: Dileep Singh, Argonne National Laboratory; KevinHoward, The Dow Chemical Company

2:00 PMOxygen contamination in erbium dihydrideC. M. Parish*, C. S. Snow, L. N. Brewer, Sandia National Laboratories, USA

Rare-earth metals, such as erbium, readily form hydride phases andcan store hydrogen in the solid-state; however, these materials alsoreadily form undesirable oxide phases. We have studied the incorpo-ration of oxygen into ErH2 in order to better understand how pro-cessing affects the structure of ErH2. Thin-films and powders of ErH2were studied via transmission electron microscopy (TEM). Energy-filtered TEM indicated that a conformal surface oxide formed on topof the hydride, and that large oxide particles were present within thehydride grains. Electron diffraction showed that the oxide formedepitaxially on the hydride, within a few degrees of a cube-on-cubeorientation. Electron diffraction also confirmed the oxide to be in theform of Er2O3. Double-diffraction calculations, high-resolutionTEM, and electron energy loss spectroscopy indicate that unexpecteddiffraction spots observed in the ErH2 diffraction patterns may arisefrom oxide nano-inclusions.

2:20 PMUnderstanding Nanomaterials for Sustainable Energy UsingAdvanced Electron MicroscopyD. J. Stokes, B. Freitag*, FEI Company, Netherlands; J. Ringnalda, FEICompany, USA; D. H. Hubert, FEI Company, Netherlands

With energy resources under increasing pressure, we need new nano-materials leading to renewable energy sources and increased effi-ciency. Tailoring nanomaterials for specific functions requires preciseunderstanding, control and visualization of structure-property rela-tions at an unprecedented level. Properties can be optimized by a fun-damental grasp of the catalytic behavior of nanoparticles and betterunderstanding of the physical properties of solar cells, fuel cells andlight sources, requiring advanced tools that allow us to see down tothe individual atoms and sense their chemical environment. It meanshaving the ability to perform experiments in situ, to follow specificchemical reactions and physical processes, and there is a need to beable to perform these tasks in multi-dimensions, spatial and tempo-ral. We have developed the tools needed for these technological andscientific insights and will show how these are related to advancingprogress in the development of new nanomaterials

2:40 PMStructural study and proton conductivity in Y-doped BariumZirconate (BZY)A. Ovalle*, A. Braun, S. Duval, P. Holtappels, T. Graule, EMPA, Swiss FederalLaboratories for Materials Testing and Research, Switzerland

Proton conducting ceramics offer new applications as intermediatetemperature solid oxide fuel cell electrolytes, hydrogen separationmembranes and sensors with superior performance compared to thestate-of the art devices. However a technically limiting factor is thestill poor conductivity. Recently in our laboratory was found that theconductivity varies by three orders of magnitude with the lattice pa-rameter. Yttrium-doped barium zirconate (BZY) is synthesized andstudied with impedance spectroscopy and quasi-elastic neutron scat-tering (QENS), with respect to its stoichiometry and domain andgrain boundary density. The proton diffusion mechanism, in particu-lar the interaction between protons and dopant atoms, is investigatedusing neutron scattering.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 62

Mo

nd

ay P

M

www.matscitech.org 63

3:00 PMThermal and Microstructure Analysis of a Cr-Hf-Si EutecticD. Lewis*, H. McGee, L. Jamison, Rensselaer Polytechnic Institute, USA

In the Cr-Hf-Si system, the ternary eutectic reaction in the Cr-richcorner was systematically investigated through microstructural andhigh-temperature thermal analysis. This eutectic reaction occurs atapproximately 1600C and involves the Laves, (Hf,Cr)5Si3, (Cr)phases. Using preliminary phase-diagram modeling results a series offifteen alloys near the predicted invariant point were prepared by arc-melting. Several compositions produced observable eutectic struc-tures, these alloys were then investigated by high-temperature DTA.This information will be used to improve thermodynamic models ofthe Cr-Hf-Si system. This will ultimately lead to improved descrip-tions of higher order Nb-Si phase diagrams for high-temperatureturbine applications and new intermetallic alloys.

3:40 PMMicrostructural Analysis of Silicon Beads Grown Using FluidizedBed MethodsM. M. Reynolds*, D. F. Bahr, M. G. Norton, A. Bellou, Washington StateUniversity, USA; E. W. Osborne, REC Silicon , USA

Using fluidized bed technology, the efficient production of ultra puresilicon is now commercially available for solar material applications.The beads produced vary in size from a few millimeters to a centime-ter in diameter. Voids on the order of 1-5 microns provide evidence ofgrowth patterns in the bead material. These growth patterns provideevidence of repeated nucleation and growth of the solid. X-Ray dif-fraction was used to demonstrate grain size as a function of thegrowth time of individual beads, and compared to electron mi-croscopy characterization. Fracture behavior of the bead product,and the change in morphology from seed material to the grown ma-terial has been documented using both optical and electron mi-croscopy. Finally, changes in grain size as a function of annealing timeand temperature are used to demonstrate parameters such as activa-tion energy, and these results are compared to that in bulk materialgrown conventionally for the semiconductor market.

4:00 PMThe photovoltaic properties of acid treated dye sensitized solarcells (DSSCs)J. Lee*, H. Jung, University of Pittsburgh, USA

The influence of nitric acid treatment on the the performance of dyesensitized solar cells (DSCs) was investigated. The surface of TiO2photoelectrodes was modified by dipping them in nitric acid. The ni-tric acid treatment of the photoelectrode increased the energy con-version efficiency from 5.4% to 6.2%, which is mainly attributed tothe increase in the photocurrent. Comparative study on HCl andHNO3 treated photoelectrodes demonstrates that the benefit ofHNO3 treatment is to suppress backward electron transfer, therebycollecting more charge carriers. X-ray photoemission and FT-IRspectroscopy studies show that the effect of the nitric acid treatmentis due to the presence of residual nitrate ions and hydroxyl groups,which decreases a free surface area and strengthens the physical ad-sorption of dyes. The present study indicates that the nitric acid treat-ment is an effective way to improve the performance of TiO2-basedDSCs via the surface anion adsorption.

4:20 PMVisible Light Sensitization of Lanthanide Containing AurivilliusPhases Via Bi 3+ SubstitutionE. J. Nichols*, S. T. Misture, Alfred University, USA

Prior authors have demonstrated that visible light sensitization ofsome Aurivillius phases is possible through the incorporation ofhighly electronegative ions, such as lead, on the A sites of the per-ovskite-like blocks. This current work is an extension of this conceptto three layer Aurivillius phases containing members of the lan-

thanide series on the A site. Bi 3+ has been chosen for this substitu-tion. Bi 3+ has an ionic radius very similar to that of the first fewmembers of the lanthanide series and electronegativity almost doublethat of these rare earth elements. The La series shifted the band gaptowards the visible range by up to 0.25eV, however, the incorporationinto the Pr series had little effect on band gaps. Photocatalytic activityfor water splitting will be discussed in the context of the stability ofthe phases and the shifts in the band gap.

Environmental & Energy Issues: Fuel Cells:Materials, Processing, Manufacturing,Balance of Plant and Systems Operation

Fundamental Electrochemical Processes: ElectrodeChemistry, Kinetics, and DegradationRoom: 325Session Chairs: Prabhakar Singh, Pacific Northwest National Lab;Colleen Legzdins, Ballard Power Systems

2:00 PMLow Cost, Nanostructured Palladium-based Alloy Catalysts forFuel Cells (Invited)A. Manthiram*, A. Sarkar, H. Liu, University of Texas at Austin, USA

One of the challenges for the cost effective commercialization of theproton exchange membrane fuel cells (PEMFC) and direct methanolfuel cells (DMFC) is the high cost and limited abundance of the plat-inum electrocatalyst. To address this issue, this presentation will focuson the design and development of less expensive palladium-based alloycatalysts; the cost of palladium is one-fifth of the cost of platinum.Novel solution-based chemical synthesis, chemical and structural char-acterization, and electrochemical evaluation for the oxygen reductionreaction in PEMFC and DMFC of nanostructured palladium-basedalloy catalysts will be presented. The catalytic activity and chemical sta-bility (durability) of these catalysts as determined by cyclic voltamme-try, rotating disc electrode (RDE), rotating ring disc electrode (RRDE),and single cell PEMFC and DMFC measurements will be correlated tothe chemical composition, microstructure, and surface structure.

2:40 PMSynthesis of epitaxial/textured cathode thin films on single crystalelectrolyte substratesB. Kavaipatti*, S. Wang, L. Yan, P. Salvador, Carnegie Mellon University, USA

Epitaxial and textured thin films, which allow for control over surfaceand microstructural features, are ideal samples to generate direct correla-tions between the surface/interface chemistry/structure and overall cath-ode performance. However, thin films of the typical perovskite-typecathode materials deposited on the fluorite-type electrolyte materialsgenerally exhibit complex microstructures and, hence, poorly controlledsurface features. Here, we discuss the pulsed laser deposition (PLD)growth and structural/surface characterization of La0.7Sr0.3MnO3 andLa0.6Sr0.4CoO3 thin films on single crystal Zr0.8Y0.2O2 (YSZ) andCe0.8Gd0.2O2-buffered YSZ substrates under different deposition condi-tions. Epitaxial and textured thin films of both perovskites were grownon the electrolyte substrates. The conditions required to attain such stateswill be discussed with respect to the important interfacial energetics (rel-evant to fuel cell microstructures) and kinetic parameters of deposition.

3:00 PMModification of Solid Oxide Fuel Cell (SOFC) Anodes with CeriumOxide Thin Films and its Effect on Sulfur ToleranceL. Tang*, C. Wu, Y. Huang, Case Western Reserve Univ., USA; Z. Liu, RollsRoyce Fuel Cell Systems USA, USA; M. R. De Guire, Case Western ReserveUniv., USA

For understanding of the sulfur tolerant behavior of SOFC anodes,nanocrystalline ceria films were deposited from aqueous solution on

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 63

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania64

commercial SOFC anodes. By modifying the anodes with thiol-ter-minated or trichlorosilane-terminated sulfonate surfactant, differ-ences in film morphology was achieved. Ceria coating before andafter anode reduction in hydrogen was studied using Focused IonBeam sectioning. It was discovered that sulfonate treatment promotesfilm deposition: for 48 hours the film thickness on sulfonate-treatedanode is ~100nm, which is approximately twice the film thickness onan untreated anode. After anode reduction, ceria coating around NiOparticles formed a textured shell, which was partially hollow and par-tially in contact with reduced Ni. Results on cell testing performancewill be related to the various treatments. Post-testing characterizationof the cells after operation in fuel streams containing up to 200 ppmH2S will also be discussed.

3:40 PMEffect of Grain Size on the Ionic Conductivity of LanthanumSilicate Apatite Fabricated by Conventional Sintering and SparkPlasma SinteringM. Ng*, M. Lin, W. Sin, Y. Yao, University of California, Irvine, USA; A. Wieg,J. E. Garay, University of California, Riverside, USA; M. L. Mecartney,University of California, Irvine, USA

Lanthanum silicate apatite (LSA) has rapid oxygen ion transport atintermediate temperatures, speculated to be via oxygen interstitials atexcess oxygen concentrations. This study examines the effect of grainboundaries on the ionic conductivity of LSA. LSA sol-gel synthesizedpowders were made using lanthanum nitrate and tetraethylorthosili-cate precursors calcined at 1200°C. Densification by spark-plasmasintering to 95% theoretical density was achieved at 1200°C with 105MPa compressive stress and translucent samples were formed. Con-ventional sintering at 1400°C produced opaque samples with 91%theoretical density exhibiting significant residual porosity. Bulk andspecific grain boundary ionic conductivity of LSA with a range ofgrain sizes (from 0.5 micron to 2 microns) were measured by imped-ance spectroscopy. The effect of the ceramic processing method ongrain growth behavior and ionic conductivity was also evaluated.

4:00 PMMicrostructure Design of Solid Oxide Fuel CellsK. Yamamoto, R. Garcia*, Purdue University, USA

With soaring oil prices and diminishing fossil fuel reserves, the devel-opment of new ways to produce electricity has become a priority.One such technology is Solid Oxide Fuel Cells (SOFC), whose ele-vated operating temperatures allow them to use a wide variety offuels. Fuel cell performance is intricately related to material proper-ties and thus a correctly engineered microstructure will increase theefficiency of the device. In this paper, the effect of particle size, crys-tallographic orientation, morphological anisotropy, porosity, etc., areengineered to maximize the delivered power density of the device.Moreover, the details and spatial distribution of triple phase bound-aries are tailored by implementing a novel numerical approach thataccounts for the local electrochemical particle-particle interactions.Alternate, non-conventional device architectures are proposed.

4:20 PMStructure – Performance Correlation of SOFC CompositeCathodesA. Duong*, D. R. Mumm, University of California, Irvine, USA

Solid Oxide Fuel Cell (SOFC) technologies offer a means of minimiz-ing emissions and increasing efficiency associated with electricityproduction. It remains a major challenge to develop electrochemicalceramic cathode systems that offer high performance with long-termstability. A promising approach to the study of cathode systems is thecompositing of ceramic materials of known electronic characteristics.Composite cathodes of a purely electronic and a purely ionic materialdemonstrate different electrochemical performance compared to thatof two MIEC materials of varying transference numbers. Such a dif-ference can be linked to the distribution of triple phase boundaries

(which have been shown to correlate with electrochemical perform-ance) in the cathode bulk. 3D reconstruction with micrograph im-ages collected using a focus ion beam were used to study these differ-ences. Porosity and TPB information extracted from thereconstructed volumes was used to correlate electrochemical per-formance with microstructure.

4:40 PMEvaluating Sulfur Tolerance in Solid Oxide Fuel Cell AnodesC. Wu*, Y. Huang, L. Tang, N. Kokkinos, Case Western Reserve University,USA; Z. Liu, Rolls Royce Fuel Cell Systems USA , USA; M. R. De Guire, CaseWestern Reserve University, USA

The sulfur tolerance of four types of YSZ-electrolyte-supported, SOFCswith LSM cathodes is being evaluated. The four types consists of cellswith either Ni/YSZ anodes or Ni/GDC anodes, either with or without aGDC layer between the anode and the electrolyte. In addition, on somecells a 50- to 100-nm thick layer of nanocrystalline cerium oxide was de-posited on the anode before testing. The morphology of the coating wascontrolled by different surfactant treatments (trichlorosilane-terminatedsulfonate treatment, or thiol-terminated surfactant treatment). The ef-fectiveness of the cerium oxide coatings, surfactant treatments, and thefour different cell designs at improving sulfur tolerance is being assessedthrough measurements of area-specific resistance, specific power, andcell lifetime under sulfur levels (as H2S) ranging from zero to 200 ppm.

5:00 PMProton conducting Solid Oxide Fuel Cells with the novel LaNbO4as the electrolyteH. L. Lein*, G. Syvertsen, Norwegian University of Science and Technology,Norway; M. Huse, T. Norby, University of Oslo, Norway; T. Grande, M.Einarsrud, Norwegian University of Science and Technology, Norway

State-of-the-art SOFCs are mostly based upon oxygen conducting elec-trolyte, however, more and more attention is drawn to the proton con-ducting oxides. Many of todays materials have quite high proton con-ductivity, but are unstable in the presence of CO2. Therefore, we havestarted focusing on a new class of materials, the niobates, which in gen-eral have lower proton conductivity, but higher stability. The preparationof the different components of the fuel cell is brought into focus. Theanode is a porous cermet of La(Sr)NbO4 and Ni made by tape casting,and is the loadbearing device. The La(Sr)NbO4 electrolyte (10-30 μm)and the porous La0.8Sr0.2MnO3 cathode are deposited by spray coating.Important parameters like particle size, pore size and viscosity of slips areinvestigated. Mechanical properties and the conductivity of the anodeare given attention. Cells are tested with H2 as the fuel on the anode sideand air on the cathode side, and obtained cell performance is reported.

Environmental & Energy Issues: NanoscaleDesign of Materials for Extreme RadiationEnvironments

Fundamentals of Nanoscale Design for RadiationDamage Tolerance IIRoom: 323Session Chair: Ram Devanathan, Pacific Northwest NationalLaboratory

2:00 PMNano Bubbles Formation in Aluminum duo to Neutron Radiation(Invited)B. Glam, D. Moreno*, S. Eliezer, NRC-Soreq, Israel; D. Eliezer, Ben-GurionUniversity, Israel

Heavy irradiation which involve a (α, n) reaction leads to productionof a large amount of helium in structure materials. Boron traces inthe level of atomic ppm, increase drastically the helium amount cap-tured in the metal as interstitials. The diffusion of the super saturated

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 64

Mo

nd

ay P

M

www.matscitech.org 65

helium creates nano-bubbles where the inside pressure increase withthe radius reciprocal. In the present investigation pure aluminumwith hundreds ppm of 10B was exposed to 1.51x1019 neutron/cm2.Hot Stage of the post radiated samples at 673K in a TransmissionElectron Microscopy was carried out with a supplementary ElectronEnergy Loss Spectroscopy analysis for the helium identification. He-lium bubble movement and nano foam formation was observed.Atomic model of the bubble development is presented and discussed.The scope of the present work is the dependency of the thickness ofthe sample in the nano-foam structure formation attributed to theregional thermodynamic state.

2:40 PMX-ray and Neutron Microbeam Methods For Studying Materials InExtreme Environments (Invited)G. E. Ice*, E. D. Specht, Oak Ridge National Laboratory, USA

Emerging X-ray and Neutron Microbeam methods make it possibleto study tiny sample volumes. This capability will allow for the devel-opment of small-volume sample chambers that can efficiently subjectmaterials to extreme environments. The ability to spatially-resolvematerials with micron and submicron beams will also allow for “sin-gle-crystal” measurements on polycrystalline or graded materials.This will enable detailed measurements of defects in real materialsand accelerated testing of materials structure evolution. For materialssubjected to extreme radiation environments, the recent demonstra-tion of diffuse diffraction from ~5 μm3 sample volumes enablescharacterization of tiny samples where the total activity can be manyorders of magnitude lower than with traditionally-sized diffuse-scat-tering samples. This capability will greatly simplify the study of de-fects in irradiated materials and will allow for studies of how pointdefects interact with mesoscale defects.

3:20 PMRadiation Tolerance of Complex Ceramics (Invited)R. Devanathan*, W. J. Weber, Pacific Northwest National Laboratory, USA

We have performed multi-million atom molecular dynamics simula-tions of energetic recoil damage in complex ceramics to understandthe fundamental mechanisms that underlie radiation tolerance of ce-ramics. By comparing the primary damage state produced by 30 keVrecoils in zirconia, zircon and pyrochlores, we have obtained insightsinto radiation damage evolution at the atomic-level. In radiation tol-erant ceramics, dynamic defect annealing is very effective and the re-sulting damage consists of isolated point defects. In contrast, in-cas-cade amorphization occurs in zircon, which is readily amorphized bythe accumulation of recoil damage. The results indicate the potentialof defect engineering for designing radiation-tolerant materials.

Environmental & Energy Issues:Thermoelectric Materials: Science,Technology and Applications

Thermoelectric Technology and ApplicationsRoom: 324Session Chairs: Qiang Li, Brookhaven National Lab; Winnie Wong-Ng, National Institute of Standards & Technology

2:00 PMMaterials for Automotive Thermoelectric Waste Heat Recovery(Invited)J. Yang*, GM R&D Center, USA

Increasing awareness and concern for energy resources and the envi-ronment has prompted the recent worldwide effort on thermoelectric(TE) materials research and technology development. Advances in TEtechnology can have a significant impact on the automotive industryin terms of fuel economy improvements by generating electricity from

waste heat and augmenting air conditioning efficiency. A critical com-ponent of developing automotive TE technologies is the discovery anddevelopment of highly efficient TE materials. From the fundamentalmaterials research perspective, this is motivated by the more than half-century-long challenge of simultaneously enhancing the electricalconductivity and thermopower, and lowering the thermal conductiv-ity of materials; and of understanding the underlying mechanisms. Inthis talk I will highlight some of our recent materials research, and au-tomotive TE waste heat recovery technology development.

2:30 PMDevelopment of some high-temperature thermoelectric materialsfor integration into advanced Radioisotope ThermoelectricGenerators (Invited)T. Caillat*, C. Huang, S. Chi, B. Cheng, V. Ravi, S. Firdosy, J. Fleurial, NASAJet Propulsion Laboratory, USA

Radioisotope Thermoelectric Generators (RTGs) have been success-fully used to power a number of space missions and have demon-strated their reliability over extended period of time (tens of years)and are compact, rugged, radiation resistant, scalable, and produceno noise, vibration or torque during operation. The Jet PropulsionLaboratory has been leading, under the Advanced ThermoelectricConverter (ATEC) project, the development of new high-tempera-ture thermoelectric materials and components for integration intoadvanced, more efficient RTGs. Thermoelectric materials investigatedto date include skutterudites, the Yb14MnSb11 Zintl phase, SiGe al-loys, and La2Te3. The synthesis, transport property measurement re-sults and some physical properties are presented and discussed forsome of these materials in the context of their integration into ad-vanced RTGs. Copyright 2008. California Institute of Technology.Government sponsorship acknowledged

3:00 PMMechanical Characterization of Selected Thermoelectric MaterialsV. Ravi*, S. Firdosy, T. Caillat, Jet Propulsion Laboratory, California Instituteof Technology, USA; A. Pushko, A. Sechrist, S. Nutt, University of SouthernCalifornia, USA; B. Lerch, A. Calamino, R. Pawlik, M. Nathal, NASA GlennResearch Center, USA

ABSTRACT BODY: The Jet Propulsion Laboratory has been leading,under the Advanced Thermoelectric Converter (ATEC) project, the de-velopment of a new generation of high-temperature thermoelectric ma-terials and components for integration into potential advanced, more ef-ficient Radioisotope Thermoelectric Generators (RTGs). Thermoelectricmaterials investigated to date include skutterudites, the Yb14MnSb11zintl compound, and SiGe alloys. The durability of these materials in re-sponse to handling, couple manufacturing and end use conditions is akey factor to achieve predictable, long-term service. The range of tech-niques used to measure the mechanical properties is described in thispaper. Additionally, the comprehensive approach taken to obtain elasticmodulii, flexural strengths, compressive strengths and fracture tough-ness will be discussed. The stiffness, strength and toughness of thesecompounds were evaluated as a function of temperature to support thedevelopment of advanced thermoelectric couples based on these materi-als. Initial results are reported and discussed. Copyright 2008. CaliforniaInstitute of Technology. Government sponsorship acknowledged.

3:40 PMAccelerating the Commercialization of Promising NewThermoelectric Materials (Invited)L. Bell*, BSST LLC, USA

Since 2000 significant technical progress has been made in the fabri-cation and laboratory scale demonstration of thermoelectric (TE)materials with substantially increased figure of merit, ZT. Operatingefficiency increases with ZT in cooling, heating and power generationdevices. Nevertheless, none of the promising new materials has beenbuilt into devices that exhibit increased system level efficiency. Thiscrucial step has eluded material developers, TE module producers

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 65

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania66

and device designers and manufacturers. The steps required to trans-form TE materials from laboratory proof-of-principle samples intomodules, and modules into devices that exhibit improved efficiencyare discussed. Criteria for TE materials for module construction, inaddition to high ZT, are presented in terms of material properties andthe form factors needed to for module fabrication. Recommenda-tions are given for actions to be taken at the material development,module fabrication and device design stages.

4:10 PMNanotechnological concepts for new thermoelectric (TE)materials(Invited)H. Böttner*, Fraunhofer Institut Physikalische Messtechnik IPM, Germany

TE converters are multitalented: they cool or exploit work heat to gen-erate electricity and do so silently, without maintenance and in partic-ular with extreme reliability. But: all TE applications depend mainlyon the material quality, in field of TE defined by the well known Z =S^2.σ/λ. It is the main goal for the material development to enhanceZ for ZT values above the critical number of 1. This will increase ap-plications and consequently the TE market disproportionately. Formodern concepts, to achieve e.g. ZT ~2, the internal structure of TEsemiconductors is based on different nanoconcepts. Here we will givean overview over different concepts and technological procedures aswell as the typical materials involved. We will focus on those tech-nologies which deal with the approach to reduce λ keeping high σ.The survey will cover PVD methods for nanoscale TE like MBE,chemical routes for self organizing TE material, as well as recentlyevaluated methods like spark plasma sintering and melt spinning.

4:40 PMDevelopment of thermoelectric modules consisting of oxidematerials and their application (Invited)R. Funahashi*, National Institute of Advanced Industrial Science &Technology, Japan

Humanity urgently requires improving the lifestyle and efficiency ofenergy use for solutions of energy and environmental problems that arenow approaching critical levels. Thermoelectric oxides possessing highdurability against high temperature and security were discovered and aprototype of small-sized cogeneration systems working at 773-1173 Kwas developed. Thermoelectric modules composed of oxide devices,which have pipe-type shapes, were constructed using Ag electrodes,paste and stainless steel pipes. Power generation was carried out inflame by combustion of natural gas. Water was flowed inside the stain-less steel pipe for cooling. The module can generate 0.27 W and hyperheated steam simultaneously by inserting in an instantaneous waterheater. Thermoelectric and mechanical properties of the thermoelec-tric oxides and fabrication of power generation modules will be shown.

Fundamentals & Characterization: CeramicSurfaces, Grain Boundaries and Interfaces

Interface Thermodynamics andSegregation/Adsorption IIRoom: 301Session Chairs: Dominique Chatain, CNRS; Wayne Kaplan,Technion

2:00 PMStabilization of Quasi-Liquid Interfacial Films: Adsorption,Disordering and Wetting (Invited)J. Luo*, H. Qian, X. Shi, Clemson University, USA

Several recent observations of equilibrium-thickness quasi-liquid in-terfacial films are discussed. First, stabilization of nanoscale Bi2O3-enriched surficial films on ZnO has been documented (Annu. Rev.Mater. Res. 2008); a recent anisotropic wetting study shows that ageneralized Cahn prewetting model applies, but the expected com-

plete wetting transition is inhibited by an attractive dispersion force(Acta Mater. 2008, 56:862). Second, similar surficial films have beenobserved for a catalyst system: VOx on TiO2 (APL 2007, 91:061909),where evidence for the existence of first-order adsorption transitionsis revealed. Finally, the stabilization of quasi-liquid surficial films isanalogous to the prewetting and premelting phenomena in simplersystems, as well as the stabilization of intergranular films in ceramicsand metals (Crit. Rev. Solid State Mater. Sci. 2007, 32:67). A long-range scientific goal is to develop interfacial complexion (phase) dia-grams as a tool for materials science.

2:40 PMRecent Advances in Grain Growth Theory and Simulation(Invited)M. Lazar, R. D. MacPherson, D. J. Srolovitz*, Yeshiva University, USA

Recently, we have derived an exact extension of the von Neumann-Mullins relation from 2-d to 3-d and, in fact, all integer dimensionsgreater than one. During this presentation, I will review this theoreti-cal development, talk about several extensions and discuss some of itsimplications for grain growth simulation. I will then present some re-sults of front tracking simulations of isotropic, normal grain growththat implicitly enforce the 120 degree triple junction. Finally, I willdiscuss extensions for anisotropic cases.

3:20 PMInterfaces of copper crystals equilibrated on different sapphireplanes (Invited)S. Curiotto*, D. Chatain, CNRS, France

When small metal drops and crystals are annealed on ceramic sub-strates, shape changes of the surfaces and interfaces occur. They tendtowards their equilibrium shape. The usually high experimental tem-perature necessary to melt or equilibrate the metal drops plays an im-portant role on the transformation kinetics. Besides, interfaces inmetal/oxide systems are very sensitive to adsorption of oxygen and cer-tain metallic species. In order to address these topics in a comprehen-sive manner, interfaces of micron size copper crystals annnealed on C,A and M sapphire planes under different oxygen partial pressures, havebeen investigated by AFM and SEM at the nano and micron scales. Wewill discuss the relationship between the chemistry of the environmentof this metal/oxide system and the morphologies of its interfaces.

3:40 PMRole of Interfacial Energy in the Stability of Grain BoundaryComplexions (Invited)S. J. Dillon*, Carnegie Mellon University, USA; M. P. Harmer, LehgihUniversity, USA; G. S. Rohrer, Carnegie Mellon University, USA

Intergranular ‘phases’ (or complexions) have been shown to be impor-tant in affecting the kinetics and properties of crystalline materials. Theassumption is that these complexions are stable because their formationlowers the free-energy of the grain boundary. However, with graingrowth the character of the boundary changes. Therefore, the stability ofthese complexions is unclear and the magnitudes of their relative energiesare unknown. This work measures the difference in relative energies ofnormal and abnormal grains of various complexions, in order to estab-lish the magnitude of this change in energy. Calculations of relative ener-gies have been made from surface dihedral angles. Similar measurementshave also been made at interphase interfaces in order to understand howthe interfacial energy of precipitates affects the tendency for complexiontransitions. This last point may be a major issue in understanding chem-istry selection for controlling grain boundary complexions.

4:00 PMAtomistic Characterization of Nanometric Films at Metal-CeramicInterfaces (Invited)M. Baram*, W. D. Kaplan, Technion-Israel Institute of Technology, Israel

As microstructural length-scales are reduced, metal-ceramic inter-faces have a critical role in determining the properties of material sys-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 66

Mo

nd

ay P

M

www.matscitech.org 67

tems. Fundamental questions regarding these interfaces include de-tails on the atomistic structure and chemistry. Over the last few years,stable nanometric intergranular films were found to exist at metal-ce-ramic interfaces. To date, most of the studied intergranular films wereassumed to be completely amorphous, due to the limited resolutionof various TEM techniques. This assumption is wrong, and adverselyaffects interpretation of the formation and existence of the films andtheir influence on material properties. The current study presents theevaluation of intergranular films at metal-ceramic interfaces formedusing a novel experimental approach. The analysis of the system wasconducted using aberration corrected HRTEM (on a site-specific FIBspecimens) to provide important information regarding the atom-istic characteristics on the films.

4:20 PMAtomic Resolution Study of the Interfacial Bonding at Si3N4/CeO2-

δδ Grain BoundariesW. Walkosz*, R. F. Klie, S. Ogut, University of Illinois at Chicago, USA; A.Borisevich, P. F. Becher, S. J. Pennycook, Oak Ridge National Laboratory,USA; J. C. Idrobo, Vanderbilt University, USA

Using a combination of atomic-resolution Z-contrast imaging and elec-tron energy-loss spectroscopy (EELS) in the scanning transmission elec-tron microscope as well as first-principles calculations, we examine theatomic and electronic structures at the interface between Si3N4 andCeO2−δ inter-granular film (IGF). Ce atoms are observed to segregate tothe interface in a two-layer periodic arrangement, which is significantlydifferent compared to the structure observed in a previous study. OurEELS experiments show (i) oxygen in direct contact with the terminatingSi3N4 open-ring structures, (ii) a change in the Ce from +3 to almost +4in going from the interface into the IGF, and (iii) significant Si diffusionfrom the ceramic into the film. Possible reasons for these observed struc-tural and electronic variations at the interface and their implications forfuture studies on Si3N4/rare-earth oxide interfaces will be discussed.

4:40 PMAtomic Structure and Pr Segregation of ZnO Grain BoundaryY. Sato*, Japan Fine Ceramic Center , Japan; T. Mizoguchi, N. Shibata, T.Yamamoto, University of Tokyo, Japan; T. Hirayama, Japan Fine CeramicCenter , Japan; Y. Ikuhara, University of Tokyo, Japan

In this study, we investigated atomic structure and segregation ofpraseodymium (Pr) atoms at zinc oxide (ZnO) grain boundary (GB).Undoped and Pr-doped ZnO single GBs were fabricated within ZnObicrystals. Transmission electron microscopy (TEM) and high-angleannular dark-field scanning TEM (HAADF-STEM) observationswere performed for the undoped and the Pr-doped ZnO GBs. GBatomic structure and segregation were also investigated by atomisticcalculations. For the GB atomic structure, we found that (i) undopedΣ7 GB has two kinds of structural units (SUs) and (ii) undoped Σ49GB has characteristic arrangement of the Σ7-like SUs. It is consideredthat the characteristic arrangement effectively relaxes local strain atthe GB. For the segregation of Pr, we found that Pr segregates at thespecific atomic columns of the GB. Comparison of the image withatomic structure of the undoped GB indicates that Pr segregates at Znsites with locally longest inter-atomic distances.

5:00 PMStability of HfO2/SiOx/Si surficial films at ultralow oxygenactivityE. Jud Sierra*, M. Tang, Y. Chiang, Massachusetts Institute of Technology, USA

HfO2/SiOx/Si layer structures have been fabricated using atomiclayer deposition and subsequently annealed at partial oxygen pres-sures close to the equilibrium pressure of bulk SiO2 by using a solidstate buffer method. An interfacial SiOx layer of ~1 nm thickness isshown to be part of the equilibrium configuration of HfO2 on Sieven at an oxygen activity 8 orders of magnitude below the equilib-rium pressure of bulk SiO2. Elimination of the silica-rich interfa-cial layer in any process permitting approach towards thermody-

namic equilibrium seems highly improbable. By comparison withthe case of pure SiOx on Si, it is shown that HfO2 acts as a “surfac-tant” to SiOx leading to a smooth film structure while the pureSiOx on Si exhibits island formation under the same conditions.Furthermore, the oxidation state of Si in SiOx and the silicate com-position at the HfO2/SiOx interface can be tailored by the partialoxygen pressure.

5:20 PMQuantitative Analysis of Interface Structures by High-ResolutionTEM (Invited)M. Ruehle*, MPI for Metals Research, Germany

Understanding the properties of interfaces requires the knowledge ofthe (three-dimensional) atomic structure of the interface with highprecision. With today’s advanced TEM instrumentation it should bepossible to get interesting results with a high reliability. Possible ap-proaches for a quantitative interface analysis will be introduced andapplied to interfaces between metals (Pd, Cr) and different oxides(SrTiO3, ZnO). TEM observations are summarized for coherent, par-tial coherent and “incoherent” interfaces. Most detailed informationwere obtained for the coherent Pd/SrTiO3 interface. The positions ofcolumns of atoms (ions) could be determined with an impressive ac-curacy. - A semi-coherent interface exists, for example, between Crand SrTiO3. An incoherent interface seems to be present between Pdand ZnO. - The results will be discussed. The most critical compo-nent is the thin TEM specimen. Implications will be presented.

Fundamentals & Characterization: Discoveryand Optimization of Materials throughComputational Design

Thermodynamic and Kinetic Processes for MaterialsOptimization IIRoom: 303Session Chairs: Stefano Curtarolo, Duke University; Dane Morgan,University of Wisconsin - Madison

2:00 PMAb Initio Modeling of Electrochemical Materials (Invited)K. A. Persson*, MIT, USA

The advances in computational methods and technology havebrought materials modeling to the point where we can accuratelyidentify current materials limitations and suggest in silico designedoptimized materials. This talk presents investigations of several mate-rials that involve challenges in today’s technologies. In Li-ion batter-ies, there is demand for improvement in energy content, safety, costand rate capability both on the anode and cathode side. For example,the carbon anode is prone to deteriorating rate capability at lowertemperatures. By studying the kinetics in the Li-C system, the mecha-nism behind the rate decline was elucidated. In low-temperature fuelcells, performance loss connected to the stability of the platinum cat-alyst is one of the major concerns. Using ab initio methods, we deter-mined the stability regions of nanoparticle Pt in water as a functionof surface adsorption, particle size, potential and pH. Thus, the originof the enhanced degradation of the nanoparticle Pt catalyst could beidentified.

2:40 PMAb initio-based Diffusion Properties for Radiation-InducedSegregation Modeling in Ni-Fe-Cr Alloys (Invited)D. Morgan*, J. Tucker, T. Allen, University of Wisconsin - Madison, USA

Point defects created in radiation environments can cause radiation-induced segregation (RIS), the process by which the local composi-tion of an alloy is altered near point defect sinks. We are using ab ini-tio methods to determine which solute-defect interactions are

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 67

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania68

dominant for RIS in Ni-Fe-Cr steels, a question which has been pur-sued experimentally for decades. For Ni rich fcc Ni-Fe-Cr we findweak binding between Fe and Cr solutes and vacancies, which rulesout proposed vacancy drag mechanisms as a dominant driving forcein RIS. We find strong binding between Cr solutes and the <100> in-terstitial, which is counterintuitive to former assumptions based onsolute size. We have also combined statistical mechanics, kineticMonte Carlo, and ab initio methods to determine diffusion coeffi-cients associated with both vacancy and interstitial migration. Thesediffusion coefficients are then used to parameterize a rate theory typemodel for quantitative RIS predictions.

3:40 PMAtomistic Insight into Defect Cluster Evolution in IrradiatedSteels (Invited)B. D. Wirth*, University of California, Berkeley, USA

Radiation damage is a central issue in many advanced technologies,from light water reactor lifetime extension to the development of ad-vanced fission and fusion power plants. Irradiation effects are initi-ated by the violent displacement of atoms from lattice sites, and ulti-mately determined by the diffusional transport and evolution ofpoint defects and their clusters, along with coupled diffusion ofsolutes and impurities. Fortunately, nature has provided hints that itmay be possible to scientifically tailor materials to be extremely resist-ant to irradiation effects by promoting the efficient recombination, or“self-healing”, of vacancy and self-interstitial point defects. This pres-entation will first introduce a hierarchical approach to modeling irra-diation effects in materials, and then present an atomistically-in-formed model for dislocation loop evolution in irradiated ferriticalloys. Finally, the scientific questions related to the development ofirradiation resistant materials will be discussed.

4:20 PMUnderstanding Structure-Property Relation in ThermoelectricNaxCoO2 by Combining First Principles with Experiments(Invited)S. Meng*, University of Florida, USA

Understanding the remarkable thermoelectric properties and inter-esting electronic/magnetic phenomena in P2-NaxCoO2 requires adetailed understanding of the structures at various sodium concen-trations. Sodium and vacancy order persist at finite temperature andcouple strongly with the electronic structure. Using first principleselectronic structure methods within the GGA and GGA+U approxi-mations we find that Na ordering is determined by a competition be-tween Na site energies difference and Na-Na repulsion. In additionthe Co-Na interlayer interaction when charge localization occurs canfacilitate the lock-in of certain ordering patterns of Na-Vacancy atsimple fraction fillings. We will compare and contrast the stable or-dering schemes obtained in this work with available experimental ob-servations. Our work shows excellent agreement with experiments, inaddition we predict a series of new ground states at concentration0.60 to 0.71.

5:00 PMThermodynamic assessment of the Ti-ZrO2 systemK. Wang, H. Y. Gao, Q. H. Dong, Y. L. Chen, G. X. Lu, H. C. Li*, Shang Haiuniversity, China

In the present work, an optimized set of Gibbs energy functions isproposed for the Ti-Zr-O ternary system to study pseudobinary sys-tem Ti-ZrO2, the ZrO2-TiO2 and Zr-O binary system are re-opti-mized as well. The parameters used of Ti-O,Ti-Zr binary system weretaken from a previous assessment of M.Cancarevic and J.L. Murray.On the basis of the calculated phase diagram of Ti-ZrO2 vertical sec-tion and the oxygen potential in Ti-Zr-O ternary system, the thermo-dynamic stability of Ti between ZrO2 was investigated and the poten-tial application of ZrO2 as refractory materials for melting titaniumalloy were explored. Finally, it is proposed to calculate the multi-sys-

tem Ti-ZrO2-Y2O3-CaO because it can provide the theoretical guideto design refractory materials of their spinels after combination oftwo or more oxides.

Fundamentals & Characterization: FailureAnalysis for Problem Solving

LitigationRoom: 304Session Chairs: Alan Johnson, Metals Research Inc.; Roch Shipley,Professional Analysis and Consulting, Inc.

2:00 PMCourt and Counsel - Panel Discussion (Invited)R. J. Shipley*, Professional Analysis and Consulting, Inc., USA

A judge and two attorneys will provide their individual perspectiveson litigation involving technical matters. Each panelist will make ashort presentation and will then answer questions from the modera-tor, each other, and/or those attending.

3:40 PMThe Admissibility of Expert Testimony (Invited)A. A. Johnson*, Metals Research Inc., USA; R. Storey, University ofLouisville, USA

In 1923, the U.S. Supreme Court ruled in Frye v. United States that, tobe admissible, scientific expert testimony must assist the trier of factin understanding or determining a fact in issue and employ methodswhich have gained general acceptance in the relevant scientific com-munity. This ruling was superceded in 1993 when, in Daubert et ux.V. Merrell Dow Pharmaceuticals, Inc., the Court ruled that the admis-sibility of scientific evidence is governed by the Federal Rules of Evi-dence. In 1999, in the case styled Kumho Tire Co. Ltd. et al. v. PatrickCarmichael et al., the U.S. Supreme Court extended this ruling to in-clude engineering and other expert testimony. Examples of rulingsbased on these opinions are presented.

4:00 PMAlternative Approaches to Litigation Involving Technical ExpertTestimony (Invited)H. R. Piehler*, Carnegie Mellon University, USA

Much of the recent judicial focus on expert testimony has been on theprocess of qualifying technical experts to testify in specific cases. His-torically several altogether different approaches to the introduction oftechnical expert testimony have been proposed and practiced, at leaston a pilot basis. These include the Science Court championed byArthur Kantrowitz, the use of court-appointed experts as in theAAAS program to identify Court Appointed Scientific Experts(CASE), and the standards for use by experts in products liability liti-gation promulgated by the ASTM. These and other alternative ap-proaches to litigation involving expert testimoy will be characterizedand evaluated.

4:40 PMAt Least Two Sides To Every Story (Invited)R. J. Shipley*, Professional Analysis and Consulting, Inc., USA

As science and engineering are “supposed to be” objective, how canthere be disagreements regarding technical issues in litigated matters?This question will be explored with case studies from the author’s ex-perience as well as published historical accounts. For example, differ-ent opinions can arise regarding what constitutes a failure or defect orwhich mathematical or experimental analyses are appropriate.Human factors are also explicitly considered in many failure investi-gations. Differing interpretations of microstructural and fracto-graphic features often arise in materials examinations.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 68

Mo

nd

ay P

M

www.matscitech.org 69

5:00 PMWhy Experts Disagree (Invited)D. McGarry*, SEA Ltd, USA; M. E. Stevenson, Enineering Systems Inc., USA

How can failure analysis experts develop nearly opposite opinions inthe same investigation? A disagreement of failure analyst experts per-plexes not only the casual observer but it causes confusion and disbe-lief in judges and juries. This presentation will address possible rea-sons for diverging opinions by having two experts on opposite sidesof a case review the logic process in reaching their respective contra-dictory opinions. This case involves the failure of a screw securing atree trimmer saw blade and the alleged circumstances surroundingthe failure that resulted in an injury to the user.

Fundamentals & Characterization: Fatigue ofMaterials: Competing Failure Modes andVariability in Fatigue Life

Crack Initiations and Variability IIRoom: 305Session Chairs: C. Bathias, University Paris 10; K. Shiozawa,University of Toyama

2:20 PMOverview of the Origin of Dual S-N Curves and CompetingFailure Modes in Engineering Materials (Invited)K. Chandran*, University of Utah, USA

Overview of fundamental material aspects that lead to dual S-N fa-tigue curves, and the associated competing fatigue failure mechanismsin engineering materials, is presented. It has been postulated that thebasic requirement is the “low” defect densities and spatial statistics ofoccurrence of fatigue-crack-initiating defects in the materials. A nu-merical simulation of how defect densities, locations and specimenvolume trigger the competition in failure modes, and thus affect theduality of S-N curves, is illustrated. It is shown that a variety of S-Ncurve shapes can result from the variations in the defect sizes, the sta-tistical likelihood that they occur somewhere in the specimen and theenvironmental sensitivity of the fatigue of the material. Problems withthe traditional S-N curves, comprising of low-cycle and high-cycleregimes are highlighted. The review also emphasizes why the conven-tional notions about the S-N fatigue curves should be revised.

3:00 PMOrientation Imaging Microscopy of Fatigue Crack Nucleation andGrowth in WaspaloyM. Oja*, VEXTEC Corporation, USA; K. Chandran, University of Utah, USA;R. Tryon, VEXTEC Corporation, USA

The effects of grain orientation on fatigue crack nucleation andgrowth in a polycrystalline nickel-base superalloy, known as Was-paloy, were investigated. Specimens were from a used forged compres-sor disk from an aircraft engine. Fatigue tests were conducted at 85-95% of the yield stress of the material, at R = 0.1. Multiple nucleationsof cracks of the order of a few grain diameters and propagation of thedominant crack were documented. Orientation Imaging Microscopy(OIM) was used to investigate orientations of grains in the cracks’ nu-cleation and adjacent areas. Cracks nucleated in either larger grains orin groups of similarly-oriented grains, collectively called as a “super-grain” due to the closeness of Schmid factors between the grains. The“supergrain” effect was seen in 8 of the 10 cracks investigated.

3:40 PMMeasuring cyclic deformation-induced variations inmicromechanical state using high energy x-raysM. P. Miller*, J. S. Park, Cornell University, USA

Due to single crystal property anisotropies, significant variations in elas-tic-plastic deformation can exist from one grain orientation to another in

a polycrystal undergoing cyclic deformation. While cyclic-induced mate-rial integrity degradation is often implicated for microcrack initation,evolution of micromechanical state most certainly also plays a role. Re-cent advances in high energy sychrotron x-ray diffraction capabilitieshave enabled new experiments for studying internal structure and stressevolution during deformation. The talk describes research conducted atthe Cornell High Energy Synchrotron Source (CHESS) focused on dif-fraction experiments conducted during cyclic deformation in order tounderstand grain scale variations that lead to microcrack initiation.Stressstate was measured at various cycles during the life of a copper sheet spec-imen. In addition to peak shift, peak width evolution was also studied.

4:00 PMRole of Competing Failure Modes in the Elevated TemperatureFatigue Variability Response of Shot-Peened Ti-6Al-2Sn-4Zr-6MoS. K. Jha*, Universal Technology Corporation, USA; R. John, US Air ForceResearch Laboratory, USA; D. J. Buchanan, University of Dayton ResearchInstitute, USA; J. M. Larsen, US Air Force Research Laboratory, USA

The effect of variability in the residual stress (RS) induced by shot-peening (SP) on the fatigue variability of the α+β titanium alloy, Ti-6Al-2Sn-4Zr-6Mo, was studied at 260°C. Competing crack initiationmechanisms were found to play a major role in the influence of SP onthe lifetime distribution. The mean-behavior was governed by sub-surface crack initiation by crystallographic faceting. Alternately, thelower-tail response was controlled by surface crack initiation fromrandomly occurring regions formed by localized SP effects producingflat, brittle-like fracture morphology at the crack initiation site. Theo-retical calculations showed that the life-limiting failures were ac-counted by crack growth from the surface crack initiation sizes ob-served in the fracture surfaces. A model, incorporating the dual failuremodes and the RS variability, was developed and applied in predictingthe probabilistic lifetime-limit with respect to the RS variables.

4:20 PMStudy on Very High Cycle Fatigue Behavior of High Strength Steelwith CFB/M Complex MicrostructureB. Bai*, X. Xu, Y. Yu, J. Gu, Tsinghua University, China

Carbide-free bainite/martensite (CFB/M) complex microstructure wasobtained through simple air-cooling for a novel high strength steel, whichdemonstrates outstanding combination of strength and toughness.CFB/M steel has higher �Kth and lower da/dN.Moreover, it is found thatthere is no horizontal part in the S-N curve forVHCF.Fracture still occurswhen the life exceeds 107 cycles. It is found that the originations of the fa-tigue crack tend to transfer from surface to the interior of the specimen asfatigue cycle exceeds 107. Besides, for many CFB/M specimens, the origi-nations of fatigue crack are not induced by inclusions, but through con-centration of fatigue strain on some kind of “soft structure”. Refinementof microstructure and reducing the size of inclusion could improve theVHCF properties of the steel. Fatigue limit of some specimens over 108cycles is more than 700MPa, which is about 50% of its tensile strength.

4:40 PMCrack Growth Properties of Sealing GlassesJ. A. Salem*, NASA GRC, USA; J. Glass, R. Tandon, C. Roth, Sandia NationalLabs, USA

Sealing glasses are used in applications such as feed through connec-tors in cryogenic tanks used to power the space shuttle. The seals arecritical to the system performance, and loss of the seal can result in acatastrophic hazard. To ensure the long term integrity of variousseals, the crack growth parameters A and n and fracture toughness ofseveral sealing glasses were measured in low and high relative humid-ity environments by using constant stress rate testing. The measuredcrack growth parameters in low humidity air were larger than thosemeasured in high humidity environments, implying that componentlifetime has strong sensitivity to the ambient environment, even whensmall scale cracks are used to generate the crack growth data.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 69

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania70

Fundamentals & Characterization:International Symposium on Defects,Transport and Related Phenomena

Defects and Transport Related to Fuel Cells andBatteries IIRoom: 307Session Chairs: Sangtae Kim, University of California, Davis; RogerDeSouza, RWTH Aachen Universtiy

2:00 PMSize effect on structure and transport in solid-oxide electrolytes:results from high-resolution multinuclear NMR spectroscopy(Invited)S. Sen*, H. Avila-Paredes, S. Kim, University of California at Davis, USA

High-resolution 89Y, 45Sc and 17O NMR spectroscopic measurementshave been carried out to systematically study atomic structure, vacancyordering and oxygen dynamics in oxygen-ion-conducting Y- and Sc-doped ZrO2 and CeO2 as a function of particle size ranging between afew nm and several μm. Significant effects of particle size on short-range structural order and oxygen vacancy ordering are observed forthe first time, in the nano-regime. For example, oxygen vacancies arefound to be preferentially associated with Ce in the nanoparticles of Y-doped ceria compared to the bulk while vacancies show preference forY atoms in nano-crystalline Y-stabilized zirconia. The detailed implica-tions of these results in (a) understanding the inter-dependence be-tween structure and transport properties in micro- vs. nano- crys-talline SEs and in (b) finding novel ways of manipulating andoptimizing the electrical properties of these materials will be discussed.

2:40 PMSpace Charge Effect on the Grain Boundary Conduction of Ce1-

xGdxO2-δδ as a Function of Dopant ConcentrationH. J. Avila Paredes*, S. Kim, University of California, Davis, USA

One of the main causes contributing to the blocking effect of thegrain boundaries on the oxygen ion conduction in solid electrolytes,such as doped ceria, is the space charge effect. The depletion of theconcentration of oxygen vacancies in the vicinity of the grain bound-ary cores, i.e. the space charge zones, due to the excess positive chargeexisting in the cores, causes a higher resistivity to the oxygen ion con-duction in these regions. The space charge effect however may not beas pronounced in highly doped samples as does in the samples withrelatively low dopant concentration. In this contribution, the grainboundary resistivities of Ce1-xGdxO2-δ ceramics with grain sizes bothin the micrometer (2-17 μm) and nanometer (15-20 nm) ranges weresystematically characterized as a function of Gd concentration by im-pedance spectroscopy. The primary cause of the grain boundary re-sistivity at different dopant concentrations will be discussed.

3:00 PMLocal Electrical and Dielectric Properties of Nanocrystalline SolidOxide Fuel Cell ElectrolytesN. H. Perry*, T. C. Yeh, T. O. Mason, Northwestern University, USA

Local electrical and dielectric properties of yttria-stabilized zirconia(YSZ, 8mol% yttria), tetragonal zirconia polycrystal (TZP, 3mol% yt-tria), and strontium- and magnesium- doped lanthanum gallate(LSGM) have been studied using the nano-Grain Composite Model(n-GCM). The n-GCM enables determination of local grain core andgrain boundary conductivities and dielectric constants, plus grainboundary widths, from the AC-impedance spectra of nanocrystallineelectroceramics. Required grain core dielectric constants were pro-vided from single crystal and microcrystalline specimen measure-ments at corresponding temperatures. In YSZ and TZP, local grainboundary conductivities were enhanced in nanocrystalline samplesvs. microcrystalline samples; however, the total conductivity de-

creased monotonically with decreasing grain size. Results will be dis-cussed in terms of grain size-dependent defect chemistry, and impli-cations for reduced temperature solid oxide fuel cells will be ad-dressed.

3:40 PMNovel proton conductivity in nano-grained fluorite oxides ofdoped zirconia and ceria (Invited)S. Yamaguchi*, R. B. Cervera, University of Tokyo, Japan; T. Yagi, TheUniversity of Tokyo, Japan; T. Fukuda, Y. Akao, S. Miyoshi, University ofTokyo, Japan; Y. Iwai, N. Kuwata, Tohoku University, Japan; K. Kobayashi,NIMS, Japan; J. Kawamura, Tohoku University, Japan; Y. Oyama, Universityof Tokyo, Japan

The ionic conductivity in nano-grained YSZ and Yb-doped ceria hasbeen examined with the emphasis of grain growth and water uptakereaction. The sample powders have been prepared by an alkoxides orcitric acid method, and are compressed into a bulk body by a highpressure condensation at 4 GPa using cubic anvil. The results clearlyshow that the proton conduction along grain boundary prevailsbelow dehydration temperatures of 450 C if the grain size is below 10n, which is confirmed by the isotope effect of the proton conductivity,while oxide ion conductivity governed by oxide penetration acrossthe grain boundary prevails at higher temperature. All protonic bulksamples of Ba zirconates doped with various acceptor dopants of lan-thanide ions prepared by the same method are also examined andcompared. The MAS proton NMR has been used to identify the pro-tons in grain boundary region.

4:20 PMDetermination of electronic and ionic space charge profiles innanocrystalline ceria thin films via blocking electrodesS. J. Litzelman*, H. L. Tuller, Massachusetts Institute of Technology, USA

Nano-ionic materials have attracted much interest as materials foradvanced energy conversion and storage technologies. As grain sizesdecrease, the inhomogeneous defect profiles within space charge re-gions can lead to variations in charge transport. Through variation ofgrain boundary properties, the electronic and ionic carrier profiles inthe space charge region may be altered. Thin films of ceria were de-posited by pulsed laser deposition, resulting in columnar microstruc-tures and grain sizes of approximately 25-40 nm. Films were modifiedby Ni in-diffusion along grain boundaries. The electrical conductivitywas measured by impedance spectroscopy and DC techniques from400 to 550 C. Deconvolution of the ionic and electronic contributionsto the total conductivity was achieved via ion-blocking electrodes.The defect profiles in the space charge region are quantitatively ana-lyzed, and implications for device stability discussed.

4:40 PMStructure and properties of thin films of SOFC cathode materials(Invited)P. Salvador*, K. R. Balasubramaniam, S. Wang, L. Yan, Carnegie MellonUniversity, USA; J. Eastmann, P. Fuoss, D. Fong, P. Baldo, B. Ingram, M.Krumpelt, K. Chang, Argonne National Laboratory, USA; B. Misirlioglu, B.Yildiz, Massachusetts Institute of Technology, USA

Cathodes in SOFCs are responsible for the overall incorporation ofO2 into the electrolyte. Optimizations of the point, interface, andsurface defect structures are needed to improve cathode perform-ance. Yet, direct correlations between all defect types and the per-formance of SOFC cathodes are lacking. Epitaxial and textured thinfilms are ideal samples to help unravel these complex interrelation-ships. In this work, we prepared atomically flat perovskite films, espe-cially of (La,Sr)MnO3-y, on a range of substrates using PLD to controltheir thickness, microstructure, and surface termination. A suite ofexperimental techniques, including in-situ synchrotron X-ray scat-tering, electrical conductivity relaxation, thermogravimetry usingpiezoelectric crystal microbalance, and electrochemical impedancespectroscopy, were used to establish the defect, physical, and struc-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 70

Mo

nd

ay P

M

www.matscitech.org 71

tural properties of films as a function of orientation, misfit strain,temperature, oxygen partial pressure, surface termination, and filmthickness.

Fundamentals & Characterization: Micro-and Nano- Mechanical Behavior of Low-Dimensional Structures and Materials

Micro- and Nano- Mechanical Behavior of Materials -Metallic Materials IRoom: 308Session Chairs: Amit Misra, Los Alamos National Laboratory; K.Jimmy Hsia, University of Illinois at Urbana-Champaign

2:00 PMSurface chemistry driven macroscopic strain effects innanoporous gold (Invited)J. Biener*, Lawrence Livermore National Laboratory, USA; A. Wittstock,Universitaet Bremen, Germany; L. Zepeda-Ruiz, M. M. Biener, LawrenceLivermore National Laboratory, USA; D. Kramer, R. N. Viswanath, J.Weissmueller, Forschungszentrum Karlsruhe GmbH, Germany; M. Baeumer,Universitaet Bremen, Germany; A. V. Hamza, Lawrence Livermore NationalLaboratory, USA

Although surfaces or, more precisely, surface atoms determine theway how materials interact with their environment, the influence ofsurface chemistry on the bulk of the material is generally consideredto be small. However, in the case of high surface-to-volume ratio ma-terials such as nanoporous gold the influence of surface propertiescan no longer be neglected. Therefore, actively controlling surfaceproperties such as diffusion barriers and surface stress by surfacechemistry should provide an opportunity to manipulate and fine-tune material properties. Here, we demonstrate that surface-chem-istry induced changes of the surface stress can generate a macro-scopic strain response in high surface area materials such asnanoporous Au. This concept can be used to directly convert chemi-cal energy into a mechanical response without generating heat orelectricity first and thus opens the door to surface-chemistry drivenactuator and sensor technologies. Prepared by LLNL under ContractDE-AC52-07NA27344.

2:20 PMMechanics of Nanolayered and Nanoporous Metal Films (Invited)A. Misra*, Los Alamos National Laboratory, USA

The dependence of flow strength, work hardening and ductility onthe layer thickness of nanolayered metallic composites has beenevaluated using a variety of deformation experiments such asnanoindentation, micro-pillar compression, and tensile testing.The factors that determine the maximum strength will be discussedfor different types of interfaces. At the smallest layer thickness of acouple nanometers, nucleation of glide dislocations across inter-faces becomes the critical unit process that determines the flowstrength of these materials. This behavior is compared with theultra-high strengths observed in nanoporous platinum films, withligament sizes on the order of 5-20 nm, where nucleation of plas-ticity events at free surfaces is the key yield mechanism. This re-search is supported by DOE, Office of Science, Office of Basic En-ergy Sciences.

2:40 PMStructural parameters and mechanical properties ofnanostructured metals produced by plastic deformation (Invited)X. Huang*, N. Kamikawa, N. Hansen, Risø National Laboratory, Denmark

In this study, we demonstrate the common structural features andmechanical behaviors in nanostructured fcc and bcc metals by taking

aluminum and interstitial free steel as examples. The nanostructuredmetals are produced by accumulative roll bonding and the structuralparameters are analyzed by transmission electron microscopy. Bothnanostructured metals show a formation of 70% high angle bound-aries but at the same time a presence of a rather high fraction of verylow angle boundaries (<2 degrees) and a certain amount of free dis-locations in the structure. These structural parameters are correlatedto the characteristic mechanical properties such as a relatively largepost necking elongation and usual responses to post process treat-ments such as annealing- induced hardening and deformation-in-duced softening. New strategies are proposed for structure and prop-erty optimization.

3:00 PMStrengthening Mechanism of Sub-micro Sized Single Crystal NiPillarsZ. Shan*, Hysitron Inc., USA; R. Mishra, General Motors Research andDevelopment Center, USA; S. Asif, O. L. Warren, Hysitron Inc., USA; A. M.Minor, Lawrence Berkeley National Laboratory, USA

Recent studies of single crystal metallic pillars with diameters of afew tens of microns or less have clearly demonstrated that thestrengths of these pillars increase as their diameters decrease, lead-ing to new models and simulations of this dramatic size effect.Through in situ nanocompression experiments inside a transmis-sion electron microscope we can directly observe the deformation ofthese pillar structures and correlate the measured stress values withdiscrete plastic events. Our experiments show that the pillars fabri-cated with a focused ion beam (FIB) initially possess a high disloca-tion density, but under compression the dislocation density will bedramatically reduced and can even leave behind a pillar completelyfree of dislocations. This phenomenon leads to clear evidence ofsource-limited deformation where atypical hardening occursthrough the progressive activation and exhaustion of dislocationsources.

3:40 PMContinuous electrical in-situ contact area measurement duringinstrumented indentationL. Fang*, C. Muhlstein, J. Collins, A. Romasco, L. Friedman, Penn StateUniversity, USA

The primary tool for mechanical characterization of surfaces andfilms is instrumented indentation using the Oliver-Pharr data analy-sis method. The resulting elastic and plastic deformation propertiessuch as the (reduced) elastic modulus and hardness are described asforce per area; however, the Oliver-Pharr method lacks a direct in-situmeasurement of contact area between the indenter and sample. Theindirect measurement of contact area via Oliver-Pharr confounds in-strumented indentation tests when characterizing dynamic proper-ties, thin films, and materials that “pile-up” around the indenter.Here, we demonstrate an electrical technique to continuously meas-ure the in-situ contact area by relating non-linear electrical contactcurrent-voltage (I-V) curves to the instantaneous contact area. As aresult, this technique gives hardness as a continuous function of ap-plied force.

4:00 PMA novel method to determine the effective zero point of contact forspherical nanoindentationA. J. Moseson*, S. Basu, M. W. Barsoum, Drexel University, USA

Accurate determination of the “zero point”, first contact betweenan indenter tip and sample surface, has to date remained elusive.Herein we outline a relatively simple, objective procedure bywhich an effective zero point can be determined accurately and re-producibly using a nanoindenter equipped with a continuous stiff-ness measurement option and a spherical tip. The method relies

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 71

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania72

on applying a data shift which insures that stiffness, S, versus con-tact radius, a, curves are linear and go through the origin. Themethod was applied to fused silica, sapphire single crystals andpolycrystalline iron with various indenter sizes, to a zero point res-olution of ≈2 nm. Errors of even a few nm can drastically alterstress vs. strain curves obtained from the S vs. a results. Ourmethod mitigates the convoluted effects of zero point and surfaceroughness, and could also be used to overcome sample-levelingproblems.

4:20 PMMacro/micro tensile deformation behavior of steel laminatesT. Tomimatsu*, Y. Kagawa, The University of Tokyo, Japan; Y. Tanaka,National Research Institute for Materials Science, Japan

Tensile deformation behavior of high-tensile steel (WT780C) andaustenitic stainless steel (SUS304) laminates, processed by hotrolling, has been studied. Laminate materials showed five timeslarger failure strain compared with freestanding WT780C layer. Thenominal stress-strain curve of the laminated specimen exhibitslarge stress-plateau region after the elastic deformation region untilmaximum nominal stress. In this stress-plateau region, deforma-tion occurred uniformly over the whole gage area and interfaceroughness between WT780C and SUS304 decreased with tensilestrain. Discussions were made on the relationship between themacro scale deformation behavior and change in microstructure ofthe laminate.

4:40 PMCyclic Hardening and the Durability of Nanostructured Nickel FilmsJ. G. Collins*, C. L. Muhlstein, The Pennsylvania State University, USA

The cyclic deformation behaviors of nanocrystalline direct currentelectrodeposited and micrograined pulse electrodeposited thin filmnickel samples were evaluated at room temperature using subsizedspecimens and noncontact strain measurement technologies. Incre-mental step tests conducted at 90% of the yield strength using either20 steps or 30 steps per block were performed until the material cycli-cally stabilized. Both the DC electrodeposited and PED nickel cycli-cally hardened and stabilized after five blocks, or approximately 20minutes, of testing. Post-fatigue tensile testing demonstrated an in-crease in tensile strength of 10% compared to the as-received speci-mens. DC electrodeposited and PED thin film nickel reached steady-state fatigue behavior in less than 20 minutes (~7 blocks). Theimplications of the hardening behavior and possible mechanisms willbe discussed.

5:00 PMApplication of Nanoindentation to Characterization of Ti(C,N)-based Cermet MaterialsH. Kim*, S. Kim, D. Kim, Korea Institute of Ceramic Engineering &Technology, South Korea; S. Kang, Seoul National Univ., South Korea

In spite of its accessibility(easy and rapidity method), traditional in-dentation testing has a limit on the length scale because this tech-nique involves optical imaging of the indent. Recently the scope of in-dentation has been enlarged down to the nanometer range throughthe development of instrumentations capable of continuously meas-uring load and displacement. In addition to testing hardness, elasticmodulus could be measured from an indentation load-displacement(P-h) curve. In this study, hard phases in Ti(C,N)-based cermets werecharacterized by nanoindentation. The hard phases in Ti(C,N)-basedcermets are composed of so-called core-rim structures, which areseveral microns according to the size of primary carbide powders.Nanoindentation can differentiate the hardness of each core or rimstructure. Using this technique, it is also tried to evaluate the mechan-ical properties of hard phases of surface modified layer resulted fromdenitriding sintering process.

Fundamentals & Characterization: Modelingof Multi-Scale Phenomena in MaterialsProcessing

Solution AlgorithmsRoom: 306Session Chair: Adrian Sabau, Oak Ridge National Laboratory

2:00 PMFast, Physically Based Algorithms for On-line Calculations ofTexture and Anisotropy (Invited)A. Brahme*, W. Myrjam, D. Raabe, Max-Planck Institut für Eisenforschung,Germany

We will present a two-step model for texture prediction. We willdemonstrate the use of Artificial Neural network (ANN) based modelfor prediction of rolling textures. The ANN is three-layered networkwith one hidden layer. The weights are calculated using a standardback propagation algorithm. A Texture component based variation ofJhonson-Mehl-Avrami-Kolmogrov (JMAK) model will be used tosimulate texture evolution during recrystallization. The main idea isto present a physically based fast model capable of making accuratepredictions. The model uses experimentally measured quantities likerolling reductions alloy content etc for the rolling simulation. Also ituses mobility, nucleation and stored energy data extracted from Elec-tron Backscatter diffraction maps as inputs to the Texture componentmodel. We will also present evidence to show the effectiveness of boththe ANN using low carbon steel data and Texture component modelwith typical recrystallization data.

2:20 PMAn Exact Solution to The Jackson and Hunt Model of EutecticGrowth and Its ImplicationsA. V. Catalina*, Caterpillar Inc., USA

The Jackson and Hunt (JH) theory of phase spacing selection duringthe growth of eutectic alloys is based on a Fourier series solution ofthe diffusion equation. Although this solution-as proposed by JH-isnot exact the theory describes fairly well the spacing selection in thecase of regular eutectics. It is not as successful, however, when appliedto irregular eutectics. Several attempts of other researchers to refinethe JH theory by relaxing some of the assumptions (e.g., constantdensity, isothermal solid/liquid interface) were still unable to give asatisfactory explanation to the peculiar behavior of the irregular eu-tectics. Up until now, however, the finding of the exact solution to thediffusion equation remained an issue yet to be addressed. It will beshown in this paper that such a solution is not only easily obtainablebut also that it provides the foundation for a more comprehensivedescription of the eutectic growth including the irregular eutecticsystems.

2:40 PMA Mixed-Integer Nonlinear Programming (MINLP) Zone Modelfor the Conceptual Design of a Carbothermic Aluminium ReactorD. I. Gerogiorgis*, Massachusetts Institute of Technology, USA

Mixed Integer Nonlinear Programming (MINLP) theory and appli-cations pervade computer-aided chemical process design and opti-mization. Petrochemical industries have benefited a lot from MINLPproblem formulations; metallurgical industries, however, are histori-cally characterized by multiphase complexity, resulting in a lack ofdetailed mathematical models. This paper presents an MINLP zonemodel developed for a carbothermic aluminium reactor, a revolu-tionary idea which entails significant control challenges. A coarse fi-nite volume discretization of the carbothermic reactor is consideredand a steady state CSTR reactor model is used at each of the resultingrectangular finite volumes to probe the mass, heat and componentbalances, via temperature-dependent physical properties. The goal is

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 72

Mo

nd

ay P

M

www.matscitech.org 73

to perform electrode placing and voltage optimization under balanceconstraints, to achieve maximization of liquid Al product and mini-mization of inevitable gas losses.

3:00 PMThe Modeling of Products Pressing in SHS-SystemsB. Sereda*, A. Jerebtsov, J. Belokon, K. Irina, ZSEA, Ukraine

The compact products of selfpropagating hightemperature synthesis(SHS) is received by hot-temperature compaction in closed matrixwith the transfer of pressure in free-flowing medium. The modellingof quasi-isostatical pressing in infinite shell with static boundary con-ditions through nonisostatical factor ξ do not consider of the sizesand external friction of shell and can not be used for an estimation ofquantitative connections between power parameters of process andexact properties of extruded stuff. The purpose of investigations isthe modelling of process of joint deforming of porous non-linear -tenacious modificators and free-flowing shell in selfcontained vol-ume of the exact sizes. The actual model on the basis of an energy bal-ance is offered. The rheological relations are obtained, which one inaggregate with the characteristics of a structural condition of stuffand kinematic ratio of plastic flow determine energy power func-tional to free parameters v1, u1 and u2.

Microstructure Evolution IIRoom: 306Session Chair: Mark Stoudt, National Institute of Standards andTechnology

3:40 PMPhase-field simulation of grain growth with inert and evolvingsecond phase particlesK. Chang*, L. Chen, Pennsylvania State University, USA

Grain growth is perhaps the most common process that occurs dur-ing materials processing, and a number of computational approachesare available to model the microstructure evolution. This presenta-tion will discuss recent progresses in advancing the phase-fieldmethod for grain growth in single- and two-phase systems. Althoughthe first phase-field model for grain growth was proposed more thana decade ago, large-scale, three-dimensional, coalescence-free graingrowth simulations became possible only recently thanks to a numberof computationally intelligent implementations that significantly im-prove the efficiency and reduce the memory requirement. We willpresent an implementation for grain growth in the presence of a sec-ond phase by combining the semi-implicit spectral method and theactive order parameter tracking algorithm. The effect of second-phasevolume fraction as well as its particle morphology and wetting condi-tions at grain boundaries on grain growth kinetics will be discussed.

4:00 PMNumerical simulation of the static recrystallization on the microshear bandsL. Madej*, Akademia Gorniczo Hutnicza, Poland; N. Yazdipour, DeakinUniversity, Australia; L. Rauch, Akademia Gorniczo Hutnicza, Poland; P. D.Hodgson, Deakin University, Australia

The recrystallization processes were extensively investigated experi-mentally and theoretically for a range of materials and process condi-tions. Initially these phenomena were described in mathematicalform and then included in finite element analysis. Assumption of thecontinuity and the deterministic character of phenomena contribut-ing to the microstructure evolution is usually the main limitation ofthis approach. One of the solutions, that overcomes these limitationsis the cellular automata (CA) method. The major advantage of theCA is that during the simulation it takes explicitly into account thegrain geometry with its features i.e. grain boundaries. The main aimof this work is application of the developed CA model to investigatethe influence of micro shear bands on the static recrystallization. The

procedure for the creation of the initial microstructure with microshear bands as well as basis of the developed CA code are also pre-sented in the paper

4:20 PMMathematical Models of Special Grain Growth Cases (Low Yttriumdoped αα-Al2O3)N. Popescu Pogrion*, I. Mercioniu, National Institute for Materials Physics,Romania; R. Bercia, M. Craiu, University Politehnica of Bucharest, Romania;S. Constantinescu, National Institute for Materials Physics, Romania

Low yttrium doped α-Al2O3 (150 ppm) material was studied usingsamples sintered by two different heating schedules. The normal fir-ing left a couple of samples (porous and compact); a protractedschedule of heating yielded nearly dense sample. The grain growth(GG) behavior of these two shows a profound divergence after a fewhours at 1650°C. For both, the GG rates were initially parabolic or alittle faster. Then, the rates for the dense samples simply suddenlydrop. In contrast, for the “porous” material the GG exhibited expo-nential kinetics, i.e. accelerating rather the normal decay. The paperestablished the mathematical models for GG. The differential simplemodels (parabolic, modified parabolic and exponential) can underlayof any “composite” models, for simulations the grains growth. Theidentification of the model parameters it isn’t easy, but it is possible touse the solutions in the explicit form, obtained for the simple models.

4:40 PMMicrostructural Evolution of Phase Decomposition Cu-Ni-Fe AlloysD. V. Melo-Maximo*, E. O. Avila-Davila, O. Soriano-Vargas, M. L. Saucedo-Muñoz, V. M. Lopez-Hirata, H. J. Dorantes-Rosales, J. L. Gonzalez-Velazquez,Instituto Politecnico Nacional, Mexico

A study of phase decomposition was carried out in Cu-Ni-Fe alloys bysolving numerically the nonlinear Cahn-Hilliard equation using thefinite difference method. Two alloy compositions, Cu-48at.%Ni-8at.%Fe and Cu-46at.%Ni-4at.%Fe, were used for the numerical sim-ulation. The simulation results indicated that the supersaturated solidsolution decomposed spinodally into a mixture of Cu-Ni-Fe rich andNi-Cu-Fe rich phases after aging at temperatures between 673, 723 and773 K. The morphology of the decomposed phases was irregular andinterconnected at the first stages of aging and it changed to a cuboidshape aligned in the <100> crystallographic directions. Besides, thevariation of modulation wavelength with aging time was slow at theearly stages of aging. In general, the simulated microstructural evolu-tion and phase decomposition kinetics showed a good agreement withthe experimental results for the same composition alloys aged at thesame conditions and analyzed by atom-probe field ion microscopy.

Fundamentals & Characterization: PhaseStability, Diffusion Kinetics and TheirApplications (PSDK-III)

Diffusion Kinetics IRoom: 302Session Chairs: Mysore Dayananda, Purdue University; JeffreyLaCombe, University of Nevada, Reno

2:00 PMFirst-principles prediction of diffusion coefficients in non-dilutealloys (Invited)A. Van der Ven*, The University of Michigan, USA

Diffusion in substitutional alloys is a complex kinetic process that de-pends on the nature of intrinsic defects, the energetically most favor-able hop mechanisms and the degree of short and long-range orderamong the constituents of the alloy. In this talk, I will describe howthese factors can be rigorously accounted for in the first-principlesprediction of diffusion coefficients in non-dilute alloys. The ap-proach relies on the evaluation of Kubo-Green expressions, which

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 73

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania74

provide the link between macroscopic diffusion coefficients andatomic trajectories sampled in kinetic Monte Carlo simulations. Afirst-principles description of the thermodynamics of short and long-range order in multi-component solids is achieved with the clusterexpansion formalism. As examples, I will describe recent work on theprediction of diffusion coefficients in aluminum alloys and in the B2-NiAl compound.

2:40 PMValidating Multicomponent Diffusivity DatabasesJ. Morral*, X. Pan, Y. Wang, Ohio State University, USA

Various methods have been developed in recent years to create diffu-sivity databases that apply to complex commercial alloys that containthree or more components. The methods include analyzing multiplediffusion couples containing small concentration differences, predict-ing diffusivities from mobility and thermodynamic databases, andextracting average diffusivities from multicomponent concentrationprofiles using the computer program MultiDiFlux. Each method con-tains inherent assumptions that can lead to diffusivities with signifi-cant errors. It will be shown in this work how errors can be detectedand how diffusivities can be properly validated.

3:00 PMKirkendall-Effect Enhanced Grain Boundary Diffusion andMigrationH. Yu*, X. Li, A. Van der Ven, K. Thornton, University of Michigan, USA

Certain alloys have significantly different mobilities of their atomicconstituents. This gives rise to the Kirkendall effect, which causes notonly marker motion, but also engineering problems such as void for-mation and growth, internal stress, and deformation. The volumechange resulting from lattice site creation/elimination needed tomaintain equilibrium vacancy mole fraction is attributed to this effect.We investigate the role of grain boundaries as vacancy sources/sinks ina binary substitutional random ideal alloy with different atomic hopfrequencies for the two atomic species. The simulation results reveal amechanism for enhancement of diffusivities near grain boundariesthat are assumed to be sources/sinks for vacancies. Furthermore, aphase field model is developed to follow the deformation caused bythe Kirkendall effect. This model results in localized deformation notexpected from the conventional theory where vacancy sources andsinks are assumed to be continuously distributed in the crystal.

3:40 PMHollow nanoparticles: formation and shrinkage by diffusion(Invited)A. V. Evteev, E. V. Levchenko, I. V. Belova, G. E. Murch*, The University ofNewcastle, Australia

There has recently been a great deal of interest in hollow nanoparti-cles for use in advanced technologies. Diffusion plays a very promi-nent role in the initial formation and ultimate shrinkage of hollownanoparticles. In this overview, we discuss the phenomenon of Kirk-endall diffusion/porosity and how it has been used in the past to syn-thesize hollow microcrystals and now nanocrystals. We summarizethe theories of stability and formation of hollow nanoparticles. Nextwe discuss the potential for hollow nanoparticles to shrink and sum-marize the theories and simulations of the shrinkage process.

4:20 PMMechanisms of Self-Diffusion along Dislocation Cores inAluminumG. P. Purja Pun*, Y. Mishin, George Mason University, USA

Dislocation diffusion is one of the least studied phenomena in mate-rial science, for which reliable experimental data is scares. The kinet-ics of many material processes have been attributed to dislocation dif-fusion. There is no concensus on the atomic mechanisms involved inthe dislocation core diffusion. We have performed molecular dynam-

ics simulations of diffusion along screw and edge dislocations withand without pre-existing point defects using an embedded-atom po-tential for aluminum. While diffusion along an edge dislocation ismediated by vacancies, diffusion along a screw dislocation occurs byan intrinsic mechanism that does not require pre-existing point de-fects. This intrinsic diffusion is due to the formation and recombina-tion of vacancy-interstitial (Frenkel) pairs in the core. The interstitialmechanism has negligible contribution in both types of dislocationbecause of their very low equilibrium concentration.

4:40 PMEffect of Yttrium on Oxygen Grain Boundary Diffusion inPolycrystalline AluminaH. Cheng*, H. S. Caram, J. M. Rickman, H. M. Chan, M. P. Harmer, LehighUniversity, USA

The “reactive element effect”, which pertains to the slowing of thegrowth kinetics of protective alumina scales on Al2O3-forming alloyswith the addition of reactive elements, such as yttrium, has been rec-ognized for some time. However, the mechanisms underlying the ef-fect are still the subject of debate. To determine the effect of Y on oxy-gen grain boundary transport in alumina, novel dual-layer samplegeometries were studied in the temperature regime 1250 to 1400 °C.The oxygen flux profile in a wedge-shaped alumina surface layer wasanalyzed by monitoring the depth of oxidation of a fine, uniform dis-persion of Ni marker particles (0.5 vol%) in the underlying alumina.By comparing the data between samples where the upper wedge-shaped layer was Y-doped (500 ppm) versus undoped alumina, theratio of the oxygen diffusivity values was determined.

5:00 PMAssessment of Diffusion Formalisms for Databases (Invited)N. S. Kulkarni*, P. J. Todd, Oak Ridge National Laboratory, USA; Y. Sohn,University of Central Florida, USA

The “mobility” formalism of Darken has been utilized for the construc-tion of diffusion databases. In this formalism, the cross-terms in thematrix of phenomenological coefficients are ignored, resulting in a sin-gle unique mobility for each component. Manning and others havequestioned the validity of this assumption suggesting that in a more rig-orous formalism, the cross-terms cannot be ignored. In a series of pa-pers, Belova and Murch have recommended the Moleko formalismrather than the Manning formalism to overcome the limitations ofManning’s random-alloy model for tracer diffusion. In this presenta-tion, these formalisms will be assessed with the aid of an intrinsic diffu-sion simulation. Current efforts with the development of a tracer diffu-sion database for Mg alloys as part of a global Integrated ComputationalMaterials Engineering (ICME) initiative will be also discussed.

Fundamentals & Characterization: RecentAdvances in Structural Characterization ofMaterials

X-Ray and Neutron Diffraction: Developments andApplications IIRoom: 309Session Chairs: Roumiana Petrova, New Jersey Institute ofTechnology; Zhonghou Cai, Argonne National Lab

2:00 PMRecent Developments and Novel Applications in X-ray Diffraction(Invited)K. Marchev*, P&G - The Gillette Company, USA; U. Preckwinkel, BrukerAXS, USA

X-ray diffraction has always been well recognized as one of the mostvaluable instrumentation methods for materials characterization anddevelopment. Following a brief overview of the fundamental princi-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 74

Mo

nd

ay P

M

www.matscitech.org 75

ples of XRD, this talk will focus on the significant advances in the re-lated technologies, electronics, and software development over thepast decade, which had drastic impact on the ways X-ray diffraction isbeing applied today. Optimal selections of sources, optics, alignmentstages, secondary beam optics, detectors, software and process au-tomation will be discussed. Presenters will discuss results from appli-cations such as powder diffraction for PhaseID, quantitative analysisand structure solutions, and morphological applications such as tex-ture, % crystalinity, SAXS, stress reflectometry and hi-resolution x-ray diffraction. Novel approaches such as in-plane diffraction, focus-ing transmission set-ups as well as the current applications ofmicrodiffraction will be explained.

2:40 PMDomain dynamics, magnetism, and high electric fields in complexoxide thin films (Invited)P. Evans*, R. Sichel, A. Grigoriev, University of Wisconsin-Madison, USA

The physics and device properties of ferroelectrics and multiferroicsare intimately linked to their structure and response to applied fieldsat the scales of single domains. Advances in x-ray scattering tech-niques now allow the structure and magnetism of thin film devices tobe at the scale of individual domains and at times down to 100 ps.This approach allows us to resolve the anisotropic relaxation of mul-tiferroic BiFeO3 thin films, the effects of this relaxation on the crystal-lographic symmetry, and the structural response of domains to ap-plied electric fields. In ferroelectric Pb(Zr,Ti)O3, domain wallvelocities can be determined under well-defined electrostatic condi-tions. Electric fields up to 5 MV/cm, more than twice the low-fre-quency breakdown electric field reveal non-linearity in the piezoelec-tric response. Magnetic x-ray scattering has the potential to allow asimilar approach to be adopted in studies of the magnetic response ofoxide thin films to applied fields.

3:00 PMEmerging opportunities in structural characterization ofengineering materials by neutrons (Invited)X. Wang*, Oak Ridge National Laboratory, USA

Neutron diffraction is a powder tool to study the mechanical behav-ior of materials. Applications have included the stress mapping in en-gineering components, in-situ loading study of deformation behav-iors, and more recently the study of damage mechanism due tofatigue and phase transformation induced plasticity. With the adventof next generation instruments at new sources, new research oppor-tunities are emerging. It will be possible, for example, to examine thedynamic process in which the stresses develop during processing oroperation. In-situ loading studies will go far beyond the status-quo ofuni-axial loading, to include torsional loading and even multi-axialloading, under elevated and low temperatures. In this talk, I will dis-cuss these new opportunities and the challenges that lie ahead interms of experiments and data analysis.

3:40 PMNanotechnology with X-rays (Invited)E. D. Isaacs*, Argonne National Laboratory, USA

Future technologies, from light harvesting for solar energy to quan-tum computing will be based on new nanoscale materials and mate-rials architectures that incorporate quantum dots, photonic crystals,laterally confined inorganic and organic thin films and synthetic mo-lecular structures. This talk discusses recent advances at the newCenter for Nanoscale Materials (CNM) at Argonne National Labora-tory, a Department of Energy scientific user facility, in the synthesis,self-assembly, characterization and theory of nanostructured materi-als for potential future technologies in energy, information technol-ogy and medicine. We highlight recent advances in synchrotron-based x-ray techniques for advanced material characterization with

an emphasis on the CNMs’ recently commissioned hard x-raynanoprobe at the Advanced Photon Source with 30 nm resolution.Nanoscience applications include catalysis at a molecular level to thevisualization of the structural and dynamical properties of magneticnanodomains.

4:00 PMNondestructive Characterization of Materials with PolychromaticX-ray and Neutron Microdiffraction (Invited)G. E. Ice*, Oak Ridge National Laboratory, USA

Powerful characterization tools are now possible due to intense newx-ray and neutron facilities. These tools offer unprecedented op-portunities to explore the underlying nano and meso-scale struc-tures in materials. Here we briefly describe three related characteri-zation techniques that provide new information about localmaterials structure and defects: (1) nondestructive submicron 3Dimaging of mesoscale crystal structures; (2) micro-diffuse measure-ments of radiation damage and defects in small or polycrystallinesamples; and (3) micro-beam neutron diffraction for characteriza-tion of small or hard-to-make crystals and for spatially-resolvedmeasurements of magnetic structures or small samples in environ-mental chambers. These techniques provide unprecedented new in-formation that can guide and challenge theory and can provide de-tailed tests of state-of-the-art models of materials behavior. Thetalk will give examples of recent results and will discuss evolvingcapabilities.

4:20 PMStudies of Fast Ferroelectric Domain Dynamics (Invited)C. Thompson*, Northern Illinois University, USA; S. K. Streiffer, G.Stephenson, Argonne National Lab, USA

The Nanoprobe beamline at the Advanced Photon Source will openup new opportunities for the study of dynamics in the nano-struc-tural response of ferroelectric and piezoelectric systems in real timeduring electrical stimulation. The Nanoprobe will provide a 30nmx-ray spot size with pulses as short as 100ps. This will allow the im-aging of the intrinsic time scales of ferroelectric switching in sub-micron structures. We will discuss how future studies of ferro-electrics may benefit from capabilities at the Nanoprobe beamline.In particular, we will compare the technical requirements and capa-bilities of various experimental designs that could be used to per-form these classes of experiments, and their relative strengths andweaknesses.

4:40 PMApplications of Polychromatic X-ray Microdiffraction for Studiesof Local Structures (Invited)J. D. Budai*, B. Larson, G. Ice, Oak Ridge National Laboratory, USA; W. Liu,Argonne National Lab, USA; J. Tischler, Oak Ridge National Laboratory, USA

High-brightness synchrotron sources have enabled the developmentof new microstructural characterization techniques. At the Ad-vanced Photon Source, we have developed a polychromatic, scan-ning microbeam facility with submicron 3D spatial resolution. Lauediffraction patterns provide the local crystal structure, lattice orien-tation (i.e. grain morphologies and texture), and elastic and plasticstrain tensor distributions from each ~micron-sized volume ele-ment. This talk will illustrate the use of polychromatic microdiffrac-tion with applications from 1D (nanostructures), 2D (films) and 3D(bulk) material systems. 1D and 2D x-ray microbeam studies pro-vide quantitative measurements that complement results from elec-tron and scanning probes. For 3D systems, x-ray microscopy pro-vides a unique, new tool for investigating how mesoscalemicrostructures affect bulk material properties and dynamics. Sup-port by Division of Materials Sciences & Engineering, U.S. DOE-BES; contract with UT-Battelle.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 75

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania76

5:00 PMProbing “Edge-Effect” of Epitaxial 1D Nanoline Using X-RayMicrodiffractionT. Sun*, Northwestern University, USA; Z. Cai, J. Wang, Argonne NationalLaboratory, USA; V. P. Dravid, Northwestern University, USA

Motivated by the novel properties and the increasing technologicalinterest based on the confinement effect of oxides, extensive scien-tific attention has been paid to the new emerging oxide-based nan-otechnology. In the presentation, we will first demonstrate the fabri-cation of epitaxially growth single-crystal CoFe2O4 nano-lines withcontrolled size and morphology on MgO substrate, using soft elec-tron beam lithography technique. In order to probe the strain fielddistribution in the vicinity of the nanoline, we have performed x-ray microdiffraction experiments at the Advanced Photon Source atArgonne National Laboratory. Specular reflection and diffuse scat-tering intensities from the MgO substrate are collected at near-Bragg incident angles. The diffuse scattering intensity has shownconsistent peak value at about 1 μm away from the line edge posi-tion. Lattice perturbation caused by the edge-induced strain field inthe substrate is considered to be a major reason for this intensityvariation.

5:20 PMMagnetic annealing aluminum alloy 6061 at 400C in differentmagnetic fieldsS. Adedokun*, J. Schwartz, FAMU-FSU College of Engineering, USA; H.Garmestani, Georgia Institute of Technology, USA; B. Ogunmola, A. Fashanu,University of Lagos, Nigeria

Aluminum alloy 6061 is widely used for structural applicationsand in sheet and plate metal industries. A plate of aluminum alloy6061 was solution heat treated and thereafter rolled down to 85%deformation to about 3 mm thickness. The deformed piece washeat treated at a recrystallization temperature of 400C at 0, 5, 10,15, 20, 25 and 30 Tesla magnetic fields for various periods of timeranging from 5 to 30 minutes. Changes in the metal was examinedby carrying out texture analysis of the samples using an x-ray dif-fractometer with texture goniometer attached. Texture evolutionswere quantified with the use of volume fractions in each of thesamples. There was not appreciable changes in the texture as themagnetic field changes, however there was an enhancement of re-crystallization when compared to when the magnetic field wasturned off.

5:40 PMThree-dimensional characterization of fatigue crack propagationbehavior in an aluminum alloy using high resolution X-raymicrotomographyH. Zhang*, Y. Sakaguchi, P. C. Qu, H. Toda, M. Kobayashi, ToyohashiUniversity of Technology, Japan; K. Uesugi, Y. Suzuki, Japan SynchrotronRadiation Research Institute, Japan

In-situ study of three-dimensional(3D) fatigue crack propagation ofan aluminum alloy was performed by using synchrotron X-ray mi-crotomography. Crack observation revealed that crack propagationwas frequently retarded in region where cracks overlapped. Propaga-tion of cracks into overlapped region was strongly constrained due tostress shielding. Crack tip opening displacement was measured and itwas found that crack opening was larger in single planar crack com-pared with that in crack overlapping region. 3D displacement of in-termetallic particles in the crack tip field was used to calculated localcrack driving force along crack front. The obtained difference incrack driving force between single planar and overlapping cracks wasexplained. Complicated crack closure behavior was observed basedon crack tip opening load measurement, and crack closure was foundto occur primarily at half the maximum applied load for the singleplanner crack.

Iron & Steel: New Developments inProcessing and Properties of Zinc-CoatedSheet Steels

New Developments in Processing and Properties ofZinc-Coated Sheet Steels IIRoom: 328Session Chair: Joseph McDermid, McMaster University

2:00 PMWater Based Silanes – An Alternate Passivation Treatment ForGalvanized Steel SurfacesD. Harrison, Australian Tube Mills, Australia; R. Walker*, C. Sclosa, BPAustralia, Australia

Australian Tube Mills produces structural hollow sections from hotrolled steel strip galvanized at its Acacia Ridge plant. Previously, whiterust resistance for galvanized tubes was provided by a 2-stage treat-ment. A conventional chromic acid solution was applied to the galva-nized strip, followed by an oil coating, applied to the finished tube -the initial chromate passivation being compromised by subsequenttube forming operations. A water-based alternative to chromate pas-sivation has now been developed. This treatment is applied after tubeforming and can replace both chromate passivation and tube oiling.The treatment produces a covalently bonded siloxane polymer filmon the zinc surface and gives equivalent white rust protection to stan-dard chromate treatments. The new treatment has delivered signifi-cant health and safety benefits to the Acacia Ridge site, and as theproduct is more easily processed downstream than oiled product, alsooffers significant customer benefits.

2:20 PMImplementation of the PAL® Program on the Baosteel No. 2 CGLH. Qian*, Teck Cominco Metals Ltd., Canada; X. Jin, Baoshan Iron & SteelCo., Ltd., China; D. Y. Liu, T. A. Cormode, N. Tang, Teck Cominco MetalsLtd., Canada

Control of the aluminum content in a continuous galvanizing bath iscritical to the quality of its products. However, adequate bath chem-istry management is difficult to achieve. Computer program PAL®(Predicting Aluminum Level), developed by Teck Cominco MetalsLtd., is a powerful tool for effective bath chemistry control. It calcu-lates zinc and aluminum consumption based on real-time produc-tion data from the line controlling computer, thereby predicts thebath aluminum content and the amount of dross formed. PAL® con-tinuously displays the bath effective aluminum content and providesan optimum ingot addition schedule to ensure that the bath alu-minum content is within the preset target. The implementation ofPAL® on the Baosteel No. 2 CGL resulted in a notable improvementin bath chemistry control. The production transition from galvanizedto galvanneal became smoother and could be predicted more accu-rately. Other benefits will also be discussed in detail.

2:40 PMStudy of the Relative Quantity of zeta and delta on GalvannealedSteel (Invited)X. Yu*, X. Jin, X. Mi, Baoshan Iron & Steel Co. LTD, China

The relative quantity of zeta and delta on galvannealed steel wasmeasured by X-rays diffraction. It was shown that the relative quan-tity of zeta and delta had a close relationship with the powdering re-sistance and friction property of galvannealed steel. It was found thatit was easy for powdering to happen when the relative quantity ofzeta and delta phase was quite low. It could be seen that the coeffi-cient of friction on coating surface rose when the relative quantity ofzeta and delta increased. In this paper, the results showed that theratio of zeta phase covering area on the coating was not linear rela-tionship with the relative quantity of zeta and delta. It was also dis-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 76

Mo

nd

ay P

M

www.matscitech.org 77

cussed that the measurement method of relative quantity of zeta anddelta could be applied for a continuous galvannealing line to monitorcoating quality.

3:00 PMZn-Fe Alloy Coating by Galvanneal ProcessM. Koushyar*, Sharif University Of Technology, Iran

In this research, the effect of heat treatment time on microstructure,alloy layers growth, paint adhesion, coating formability, corrosion re-sistance of pained coated steel and chemical composition of coatingwith optimum properties have been considered. The results show thatby extending heat treatment time the thickness of alloy layers simulta-neously changed with different rates and the coating propertieschanged by converting alloy layers and Iron content. Paint adhesionimproved by converting the Eta phase layer to zeta and appearing mi-crocracks and rougher surface. Thus, corrosion resistance of paintedsamples improved. But by increasing Iron content of coating in ex-tended heat treatment time, the corrosion resistance and coating adhe-sion decreased. The optimum Galvanneal coat characteristic have seenafter 55 second heat treatment in 530 °C .In this situation paint adhe-sion increased to 3Mpa and corrosion resistance increased; but by in-creasing the heat treatment time corrosion resistance decreased again.

Iron & Steel: Recent Developments in SteelProcessing

Heat TreatmentRoom: 329Session Chair: Riad Asfahani, U. S. Steel Research & Technology

2:00 PMImproved Annealing Furnace Control for Fuel Efficiency and CycleTime ReductionT. C. Karnezos*, Pennsylvania State University, USA; G. Dispensa, CarpenterTechnology Corp., USA; R. Voigt, Pennsylvania State University, USA

Operator load-to-furnace color matching for annealing furnace controlintroduces process variation resulting in inconsistencies in heat treatedsteel products, long heat treatment cycle times, and excessive energyconsumption. An advanced control algorithm can potentially yieldmore consistent products, save time, and conserve energy. A project iscurrently underway to develop such an algorithm for large natural gasfired annealing furnaces. Enhanced process monitoring will be achievedthrough the implementation of advanced load and furnace sensors,such as infrared thermometers and gas flow meters. Based on the outputof these sensors, the annealing cycle will be controlled in a manner thatautomatically adjusts for furnace dynamics and furnace loading. Tran-sient one-dimensional heat conduction modeling will validate the newcontrol method and will be integrated into the final control algorithm.

2:20 PMInvestigation into the Effects of Hydrogen introduced into AISI8620 Steel Parts during Long Carburization Cycles inEndothermic AtmospheresP. Ganeff*, Xtek, USA

This paper will examine whether any deleterious effects are producedin steel samples when hydrogen is introduced through extended car-burization cycles in endothermic atmospheres. The specimens testedwere composed of AISI 8620 steel, and the carburization cycles thatwere used took place over long periods of time, >150 hours at 1800°F.Chemistry measurements of the hydrogen content were taken fromboth the surfaces of samples and from the centers immediately aftercarburizing. It was found that the highest hydrogen content recordedwas approximately 2.6 ppm, substantially below the solubility limit ofhydrogen in austenite. The chemistry results comapred well, however,with predictions made using Sievert’s Law. Cores were sectioned outof the center, so that tensile tests could be performed. The results of

the tensile tests provided no evidence for the presence of significantlevels of hydrogen embrittlement.

2:40 PMUse of Dual Stabilization Thermal Processing to Increase theAustenite Content of AHSSG. M. Michal*, A. H. Heuer, Case Western Reserve University, USA

The strength/ductility goals of a new generation of advanced highstrength steel (AHSS) can be achieved by employing a microstructureof martensite plus austenite having a tailored degree of stability. Theuse of two stabilization steps in the cooling path after the annealing of acold rolled steel has the potential to maximize the amount of austenitethat can be retained in relatively lean alloys. Rapid cooling must be uti-lized to avoid the bainite transformation and reach the first stabiliza-tion point. Further cooling to create martensite is followed by heatingto a partitioning temperature which is the second stabilization point.To suppress the formation of carbides that would remove carbon andreduce the stability of the austenite, the partitioing temperature mustbe aligned within the bay that exists between the carbide precipitionTTT curves for steels alloyed with Al and Si. The results of laboratorytrials aimed at exploiting dual stabilization processing will be discussed.

3:00 PMGas Carburized/Oil Quench or Low Pressure Carburized/HighPressure Gas Quench: A Model Comparison of Distortion andResidual StressesG. Wang, M. Maniruzzaman, Y. Rong, R. D. Sisson*, Worcester PolytechnicInstitute, USA

At this time two different heat treating processes may be consideredfor the carburization heat treatment of gear steels like 9310 – GasCarburization with Oil Quench and Low Pressure Carburization withHigh Pressure Gas Quench. While both carburization processes ab-sorb and diffuse carbon into the steel to form equivalent case depths,these processes are distinctly different during quenching. The heattransfer coefficients during cooling vary in magnitude as well as withtemperature. In this paper the effects of this variation in cooling per-formance will be reported based on the results of a finite elementmodel prediction. The differences are discussed in terms of hardnessvariations as well as residual stress and distortion predictions.

3:40 PMAnalysis of Rolling Contact Fatigue Failures in High TemperatureGas Carburized Gear SteelsM. Bykowski*, J. G. Speer, G. Krauss, Colorado School of Mines, USA

The purpose of this study was to evaluate the failures in two gas-carbur-ized commercial grade gear steels subjected to rolling contact fatigue(RCF) testing. In addition to gas carburized and hardened and reheatedsamples whose life results were reported earlier, a low-pressure (vac-uum) carburizing treatment was performed to assess the influence ofthe absence of intergranular oxidation (IGO) on RCF performance.RCF testing employed a modified ball-rod RCF tester and Weibullanalysis to interpret the life results. SEM was used to observe wear tracksand pits of failed specimens to evaluate the failure mechanism. Decar-burization was found on the surface of reheated samples that exhibitedreduced life.Vacuum carburized specimens showed significantly higherlife compared with the gas-carburized samples. Micropitting resem-bling prior austenite grain pullout seemed to be influenced by IGO, andmay have caused the macropitting failures that defined the RCF lives.

4:00 PMEffect of Alloying Elements and Austenitizing Temperature onHardenability of Low-Carbon Boron-Added SteelsB. Hwang*, D. Suh, S. Kim, Korea Institute of Materials Science, South Korea;S. Lee, D. Lee, POSCO, South Korea

Effect of alloying elements and austenitizing temperature on thehardenability of boron-added steels was investigated. The boron-added steels were fabricated by varying alloying elements such C, Cr,

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 77

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania78

Mo, Nb, V, etc., and then the transformation products obtained fromdifferent cooling rates and austenitizing temperatures and their hard-ness were quantitatively examined. Molybdenum is found to be moreeffective than the other alloying elements for improving hardenabil-ity of boron-added steels. On the other hand, effect of austenitizingtemperature on hardenability of boron-added steels is varied de-pending on alloying elements. Possible mechanism on hardenabilityenhancement of boron-added steels is discussed in terms of the influ-ence of alloying elements and austenitizing temperature on the segre-gation and precipitation behaviors of boron during cooling usingsecondary ion mass spectrometry (SIMS) and transmission electronmicroscopy (TEM).

4:20 PMDevelopment of a 50Kg-grade Dual Phase Steel Using OrthogonalDesign MethodS. Kim*, Y. Cho, Seoul National University , South Korea; C. Oh, KoreaInstitute of Materials Science, South Korea; D. Kim, M. Mun, HYSCO, SouthKorea; H. Han, S. Hong, Seoul National University , South Korea

A 50Kg-grade cold rolled dual phase (DP) steel was developed basedon the orthogonal design method, which is known to be an extremelyefficient method finding the optimal experimental conditions. Theintercritical annealing, aging and galvanizing temperatures duringthe heat treatment of the DP steel were considered as controllable fac-tors and three levels for each of these factors were selected. The opti-mal experimental conditions were acquired by the analysis of vari-ance (ANOVA) on the ultimate tensile strength (UTS) and the totalelongation of the DP steel. A dilatometry analysis was carried out tomeasure the phase transformation kinetics of the DP steel and to ver-ify the statistically analyzed results. These metallurgical observationsexplained well the statistically analyzed results based on the orthogo-nal design method.

4:40 PMMechanism Responsible for Enhancement in Wear Resistance ofTool Steels by Cryogenic treatmentD. Das*, A. K. Dutta, Bengal Engineering and Science University, Shibpur,India; K. K. Ray, Indian Institute of Technology - Kharagpur, India

In the present study, an attempt has been made to reveal the underly-ing mechanism responsible for the enhancement in wear resistance oftool steels by cryogenic treatment through comparative analyses ofthe microstructures and sliding wear behavior of cryogenicallytreated vis-à-vis conventionally treated AISI D2 steel. The mi-crostructural characterizations have been done by using XRD andEDX analyses, and optical and SEM microscopy coupled with imageanalyses. Microstructural characterizations reveal that cryogenictreatment, in comparison to conventional treatment, almost com-pletely removes the retained austenite and promotes the formation ofhigher amount of secondary carbides with refinement of its size andbetter uniformity in its distribution. Modification of secondary car-bide precipitation apart from the reduction in retained austenite con-tent is found to be the governing mechanism for the enhancement inwear resistance of tool steels achieved by cryogenic treatment.

Iron & Steel: Steel Product Metallurgy andApplications

Multiphase Microstructural Process DevelopmentRoom: 330Session Chair: Abdelbaset Elwazri, McGill University

2:00 PMMicrostructure and Toughness of Martensitic Steel (Invited)J. W. Morris*, University of California, Berkeley, USA

The creation of a tough martensitic steel begins with the substructureof the martensite itself, which must be dislocated, normally lath

martensite. To minimize elastic energy the austenite grains withinsuch a steel subdivide during transformation into “blocks” in whichlaths of dislocated martensite are in close crystallographic alignment.The crystallographic relation between blocks permit grain refinementfor toughness: the microstructure may be made ultrafine-grainedwith respect to fracture without becoming so strong (via the Hall-Petch effect) that toughness is lost to high strength. This grain refine-ment can be accomplished in at least two ways: by direct “block re-finement” through appropriate thermal or thermomechanicalprocessing, or by intercritical treatments that interpose layers of crys-tallographically active austenite along interlath boundaries within thepackets.

2:20 PMFormation of Ultrafine Grained Structure by Dynamic Strain-Induced Transformation (Invited)H. Beladi*, Deakin University, Australia; Y. Adachi, National Institute forMaterials Science, Japan; P. D. Hodgson, Deakin University, Australia

In the current study, the role of dynamic strain induced transforma-tion process (DSIT) on ferrite grain refinement is investigated usingsteels with different quench hardenability. Also, a Ni-30Fe austeniticmodel alloy is employed to study the deformation structure evolutionin the DSIT. It was revealed that the extreme refinement of ferrite ismore likely due to the formation of extensive high angle intragranu-lar defects through deformation. The thermomechanical parameterssuch as strain, austenite grain size and deformation temperature af-fect the intragranular defects characteristics resulting a change in theextent of ferrite refinement. In addition, there was a transition in thedeformation temperature in which cell dislocation structure changedto laminar microband structures with a decrease in the deformationtemperature. Moreover, the potential of intragranular defects doesnot significantly reduce by recovery.

2:40 PMMicrostructures and Mechanical Properties of Ultrafine-GrainedSteel (Invited)A. Elwazri*, P. Wanjara, R. Varano, G. R. Stewart, S. Yue, J. J. Jonas, McGillUniversity, Canada

Grain refinement is an important technique for obtaining highstrength and toughness in steels. Dynamic strain induced transfor-mation (DSIT) appears to be a powerful grain refining technique.However, there appears to be a difference between deformation abovethe non equilibrium transformation temperature (Ar3) but below theequilibrium transformation temperature (Ae3) and below Ar3 butwithin the intercritical region (Ar3-Ar1). The present study exploresthese differences through an examination of inter-relation of the flowbehavior, microstructural evolution and mechanical properties.

3:00 PMMechanical properties of ultrafine and fine grained dual phasesteels (Invited)D. Ponge*, M. Calcagnotto, D. Raabe, Max-Planck-Institut fuerEisenforschung, Germany

The effect of grain size on the mechanical properties of ultrafine dualphase steels was investigated. Ultrafine grained dual phase (UFG-DP)structures in a plain C-Mn steel were produced by warm deformationand subsequent intercritical annealing. The microstructures werecharacterized by high-resolution EBSD and the mechanical proper-ties by tensile tests. Suitable intercritical annealing parameters havebeen worked out to obtain a martensite fraction of around 25 vol.%and to avoid grain growth. The microstructure consists of martensiteislands embedded in an ultrafine grained polygonal ferrite matrixand small amounts (~3 vol.%) of retained austenite. The UFG-DPsteel exhibits continuous yielding, a high initial strain hardening rateand a tensile strength of more than 800 MPa. In order to investigatethe effectiveness of refining the microstructure of dual phase steels, a

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 78

Mo

nd

ay P

M

www.matscitech.org 79

range of grain sizes between 1 and 20 μm was produced. The effect ofgrain size on strength and elongation was studied in detail.

3:40 PMDissolution and Precipitation kinetics of Nb(C,N) in austenite of aNb-microalloyed steelJ. Park*, Y. Ha, YONSEI University, South Korea; S. Lee, Yonsei University,South Korea; Y. Lee, YONSEI University, South Korea

The dissolution and the precipitation kinetics of Nb(C,N) in bothstrain-free and strained austenite of a Nb-microalloyed steel were in-vestigated using electrical resistivity and TEM. Interrupted compres-sion and electrolytic dissolution methods were used to determine theprecipitation kinetics of Nb(C,N) in strained austenite. The dissolu-tion temperature of the 0.08C-0.038Nb steel was about 1230C for 600s. The isothermal precipitation kinetics of Nb(C,N) in austenite wasaccelerated with increasing strain, and the particle distribution be-came more random. The precipitation-time-temperature (PTT) dia-grams of the Nb(C,N) precipitates in austenite with strains were gen-erated. In strain-induced precipitation of Nb(C,N), the interruptedcompression and electrical resistivity methods show more reasonablekinetics, compared to the electrolytic dissolution method. The elec-trical resistivity method has wider applications to the dissolution andprecipitation kinetics in microalloyed steels.

4:00 PMInfluence of Recrystallization Conditions on the Tensile Propertiesof a High Mn TWIP SteelS. Kang*, Y. Jung, YONSEI University, South Korea; J. Jun, Korea Institute ofIndustrial Technology, South Korea; Y. Lee, YONSEI University, South Korea

Recently, the TWIP steels have been an issue to steel and auto makersbecause of their excellent combination of strength and ductility. Thegood mechanical properties are closely related to twin formation indeformed austenite. Because there are no phase transformations inthe TWIP steels during hot rolling or heat treatment, the recrystal-lization is an important parameter for controlling the austenite grainsize and mechanical properties of the TWIP steels with a given chem-ical composition. In this study, the tensile properties of Fe-18Mn-0.6C-1.5Al TWIP steel annealed at different recrystallization condi-tions were investigated. Tensile tests were performed at a constantstrain rate of 10-2 s-1 at room temperature. Microstructural analysiswas done using optical and scanning electron microscopes.

4:20 PMEffect of carbon contents on the microstructure and thetransformation kinetics of super bainitic TRIP steelK. Lee*, Y. Im, POSCO, South Korea; H. Bhadeshia, POSTECH, South Korea;K. Chin, POSCO, South Korea

To meet the demand of both ultra high strength and enhanced forma-bility, there have been recently growing interests in TRIP (TRansforma-tion Induced Plasticity) steels with TS x El > 30,000 MPa % in the re-gion of so called X-AHSS. Finer bainitic microstructure related withlow temperature transformation in high carbon TRIP steel is known tobe beneficial to obtain ultra high strength above 2GPa. However,bainitic transformation is very sluggish due to high carbon contentsand very low transformation temperature, and takes even several days.In this study, the effect of carbon contents has been investigated on thetransformation time applicable to mill process as well as bainitic platethickness. Transformation time was reduced to several hundreds sec-onds by reducing carbon contents, and the plate thickness obtained wasin good agreement with the one predicted by theoretical calculation.

4:40 PMInfluence of cooling process after hot rolling on mechanicalproperties of cold rolled TRIP steelS. Kim*, Y. Jin, J. Kwak, K. Chin, POSCO, South Korea

This paper examines an effect of initial microstructure before inter-critical annealing on mechanical properties of cold-rolled Transfor-

mation Induced Plasticity (TRIP) steel sheets. For this purpose, wehave investigated the effects of cooling pattern after hot rolling andreduction of cold rolling on recrystallization behavior of the steelduring intercritical annealing. It has been found that the increment ofcold reduction increases the rate of recrystallization during intercriti-cal annealing. What is more, the increment of volume fraction ofmartensite phase in hot band as much as cold reduction is effective inincreasing the rate of recrystallization. In addition, the presence ofmartensite phase leads to the homogeneous distribution of cementiteand the nucleation from ferrite to austenite phase transformationduring intercritical annealing. The elongation of TRIP steel havingmartensite phase in hot band is about 20% higher than that of TRIPsteel without the phase.

5:00 PMAtomic scale investigation by using Cs-corrected STEM and APTin TRIP steelsN. Lim*, J. Kang, G. Gu, C. Park, POSTECH, South Korea

In this study, correlation between alloy segregation and microstruc-ture was investigated in thermo-mechanically processed C-Mn-Sitransformation induced plasticity (TRIP) steels, alloyed with P, Al andN. The microstructures of TRIP steels were investigated by using ad-vanced analysis techniques, such as Cs-corrected scanning transmis-sion electron microscopy (Cs-corrected STEM) and three dimensionalatom probe tomography (3D-APT). At first, the partitioning of ele-ments in the multiphase TRIP steels was investigated using Cs-cor-rected STEM. In addition, 3D-APT was used to characterize atomic-scale partitioning and segregation of added elements at the phaseinterface. Through these analysis techniques, the advanced character-istics of constituent microstructure in TRIP steels such as ferrite, bai-nite, martensite and retained austenite were identified. Finally, a non-uniform distribution of C, Mn and Si between bainitic and polygonalferrite matrix and retained austenite was observed in atomic scale.

Materials & Systems: Advances in Biomedicaland Biomimetic Materials

Scaffolds for Tissue EngineeringRoom: 333Session Chair: Roger Narayan, University of North Carolina

2:00 PMEngineered Nanofibers with Stem Cells for Biomimetic TissueEngineering (Invited)S. Ramakrishna*, National University of Singapore, Singapore

Attempts have been made to fabricate scaffolds to mimic the chemicalcomposition and structural properties of extracellular matrix (ECM)because one would think that a tissue-engineered scaffold with thesecharacteristics will have a better chance at enhancing tissue regenera-tion. Nanofibers scaffold with versatile patterns have been successfullyand relatively simple produced from many synthetic and natural poly-mers through the nanotechnology of electrospinning. Those patternsmay mimic the diversity of tissue-specific orientation of fibers. Sev-eral studies have been conducted on mesenchymal stem cells (MSCs)and hematopoietic stem cells (HSCs) attachment on electrospun col-lagen nanofibers and synthetic nanofibers. However, the significanceof certain type of nanotopography or combination of several types ofnanotopography in directing the expansion and differentiation ofstem cells is need to be demonstrated further in the future.

2:40 PMEngineering Living Cells: The Next Generation in Healthcare(Invited)S. Jayasinghe*, University College London, United Kingdom

Engineering living mammalian cells present attractive possibilitiesfor a plethora of applications within our healthcare. Such approaches

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 79

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania80

imply many promising possibilities in regenerative and therapeuticmedicine. In this endeavour, the physical sciences are increasinglydemonstrating a pivotal role, by both advancing existing cell engi-neering methodologies and unearthing new approaches, for the di-rect handling of biological materials. In this talk, the author will in-troduce and focus on recent advancements made in jet-basedtechniques, which are demonstrating huge potentional for a widerange of biotechnologies. Successful development of these bio-proto-cols sees the emergence of unique future strategies within a clinicalenvironment having far reaching consequences to our healthcare.

3:00 PMALD Surface Modified Porous Polymer for Tissue EngineeringApplicationsX. Liang*, D. M. King, A. D. Lynn, S. J. Bryant, A. W. Weimer, University ofColorado, USA

A novel porous polymer/ceramic composite material was synthesizedby depositing ultra-thin ceramic films on highly porous poly(styrene-divinylbenzene) (PS-DVB) particles using a low-temperature atomiclayer deposition (ALD) process in a scalable fluidized bed reactor.Alumina and titania films were deposited by the alternating reactionsof trimethylaluminum (TMA) and H2O at 33 °C, and titanium tetra-chloride (TiCl4) and H2O2 (50 wt.% in H2O) at 100 °C, respectively.Analytical characterization revealed that conformal alumina and tita-nia films were grown on internal and external polymer particle sur-faces. The ceramic coatings can improve the bioactivity and proteinadsorption of the polymer substrate, but did not affect the viability ofcells. The bioactive behavior of the composites was assessed by theformation of bone-like apatite on the material surfaces in a simulatedbody fluid (SBF). The improved protein adsorption of the compositeswas assessed by soaking the composites in fetal bovine serum (FBS).

3:40 PMLaser Processing of Advanced BiomaterialsR. J. Narayan*, A. Doraiswamy, University of North Carolina, USA; A.Ovsianikov, B. Chichkov, Laser Zentrum Hannover, Germany

Lasers may serve to create novel medical devices with unique biologi-cal functionalities. For example, lasers offer a unique opportunity formicroscale processing of materials. We have recently developed mi-crostructured medical devices and scaffolds for tissue engineeringusing laser direct writing and two photon polymerization processes.For example, we have used two photon polymerization for rapid pro-totyping of microneedles and ossicular replacement prostheses. Inaddition, we have developed differentially adherent surfaces usinglaser direct writing. In this work, channels were micromachined ontoagarose surfaces using an argon fluoride excimer laser and filled withextracellular matrix solution. Mammalian cells were then allowed toproliferate on the surfaces of these micromachined channels. Our re-sults demonstrate that laser-based rapid prototyping techniques maybe used to fabricate advanced biomaterials with a larger range of sizes,shapes and materials than conventional microfabrication techniques.

4:00 PMIn vitro evaluation of bioinspired ceramic microstructuresprepared by freezing of suspensionsQ. Fu*, M. N. Rahaman, University of Missouri-Rolla, USA; S. B. Bal,University of Missouri-Columbia, USA; R. F. Brown, University of Missouri-Rolla, USA

The aim of the present work was to evaluate the influence of ceramicmicrostructures on in vitro cell response. Hydroxyapatite (HA) scaf-folds with lamellar, rectangular, or cellular microstructures were pre-pared by unidirectional freezing of suspensions. Microstructuralmanipulation was achieved by modifying the solvent composition.The effects of microstructural variation on the cell growth, prolifer-ation, and mineralization were evaluated using the MLO-A5 cellline. MTT, alkaline phosphatase (ALP), and Alizarn Red Staining as-says indicated that the HA constructs with the cellular microstruc-

ture provided the most favorable substrates for cell ingrowth andmineralization. The consequences of the in vitro cell culture resultsfor creating scaffolds tailored for bone repair and regeneration arediscussed.

4:20 PMGum Arabic-Chitosan Composite Biopolymer Scaffolds for BoneTissue EngineeringO. C. Wilson, R. Silva*, O. Ogubuzo, S. McClellan, Catholic University , USA;P. Mehl, Catholic University, USA

Biopolymer composites are a very promising area for developingnovel tissue engineering scaffolds. Chitosan is known to have a vari-ety of properties that make it suitable for TE applications due to it’sbiocompatible, antibacterial, and biodegradable nature. Gum Arabic(GA) is a natural biopolymer that is incorporated into a number offood products. A biopolymer composite was synthesized by mixingGA with Chitosan in amounts ranging from 0-90 wt% GA. The addi-tion of GA caused a marked increase in the weight gain due to wateruptake that the composite films exhibited. 100% chitosan filmsgained approximately 50 wt% on aging in water while 17 wt% chi-tosan - 83 wt% GA films gained over 300 wt% due to water absorp-tion. MC3T3-E1 mouse pre-osteoblast cells were used in an initial as-sessment of the suitability of these scaffolds for bone tissueengineering. The cells adhered to the composite films and exhibitedminimal toxicity.

4:40 PMFracture Forces in Femurs Implanted with PMMAD. Dragomir-Daescu*, H. E. Brown, N. Anguiano-Wehde, S. McEligot, J. T.Bronk, K. E. Bennet, M. E. Bolander, Mayo Clinic, USA

Thirteen cadaver femurs including five normal, two osteopenic andsix osteoporotic were fractured in a materials testing machine. Threeosteoporotic femurs were injected with PMMA in the neck regionwhile their contralaterals were used as controls. During fracture, allboundary loads were measured using load cells attached to a customdesign fixture. A total of eight forces and moments, machine headdisplacement and time were recorded simultaneously. Photographsfrom two orthogonal directions captured the geometry of the femurin the fixture. Using test geometry and recorded signals, a detailedbiomechanical analysis was performed to understand the fractures.The analysis confirmed that PMMA reinforced the osteoporotic fe-murs which fractured at larger loads compared to controls. The rein-forced femurs’ fracture forces were similar to those of osteopenic andnormal bones. Their fracture patterns more closely resembled thoseof normal femurs than those of osteoporotic femurs.

5:00 PMDevelopment, synthesis and characterisation of porousbiomaterial scaffolds for bone tissue engineeringK. K. Mallick*, University of Warwick, United Kingdom

Porous bioscaffold network structures of hydroxyapatite, tricalciumphosphates, Bioglass® as well as their composites have been fabri-cated using variation of camphene, glycerol and ice based freeze cast-ing techniques. Molten ceramic slurries with 10-60% loading werecast at ambient temperature and cooled followed by sublimation attemperatures between -70 - 60 C. The green bodies sintered in air to amaximum temperature of 1050 C produced excellent 3-D intercon-nected structures with open pores. The pore channels varied fromglobular to dendritic and the analysis of loading, microporosity, poresize distribution and pore pathways proved particularly useful to as-sess the suitability of these scaffolds for bone tissue engineering ap-plications. DTA-TG, SEM, XRD, density, and strength data were usedto characterise precursors, slurry and sintered products. Biologicaland AFM studies suggested excellent surface properties amenable toappropriate cell adhesion.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 80

Mo

nd

ay P

M

www.matscitech.org 81

5:20 PMProspects of Complex Engineered Nanostructured Materials andHybrid Delivery Systems for Bone Regeneration (Invited)P. Kumta*, C. Sfeir, University of Pittsburgh, USA

Tissue engineering and nanotechnology in recent years have broughtan extraordinary transformation in the biomaterials field. Conse-quently, new biodegradable scaffolds containing functionalized carri-ers have led to the development of novel drug, protein, growth fac-tors, DNA, including stem cell delivery systems. Innovative 3-Dprinting of complex biological structures has additionally provided aunique manufacturing platform. There is still much to be desiredwith regards to providing a viable clinical therapy for bone regenera-tion. This presentation will discuss the collaborative efforts to gener-ate next generation concepts for bone regeneration utilizing a uniquecombination of novel nanostructured calcium phosphates(NanoCaPs) particulates, NanoCaPs-biologics gel based hybrid struc-tures including injectable CaP containing bio-cements that can serveas carriers of proteins, plasmid DNA, and cells.

Materials & Systems: Advances inCharacterization and Modeling ofCementitious Materials

New Developments Regarding ExperimentalTechniques for Characterizing Cement-basedMaterials IRoom: 331Session Chair: Zachary Grasley, Texas A&M University

2:00 PMPore Solution Analysis in Ordinary Portland Cement PastesPartially Replaced with Geothermal WasteC. A. Iñiguez-Sánchez*, L. Y. Gómez-Zamorano, Universidad Autónoma deNuevo León, Mexico

An investigation was carried out on pastes of Portland cement substi-tuted by a geothermal waste obtained as a byproduct from a powerplant that use geothermal underground resources. The waste is pre-dominantly nanometric amorphous silica with sodium and potas-sium chlorides. Pastes with 0, 10, 20% of GW and 0, 10, 20% of chlo-rides, cured at 10, 20 and 60°C were used to evaluate the compressivestrength, analyze the phases formed in the presence of chlorides bymeans of XRD and SEM, and estimate the calcium hydroxide contentby TGA. Pore solution tests were carried out using pore pressing andlixiviation, which is an alternative technique that could provide amore easily and efficiently method of analysis. The blended cementspresented an intense consumption of calcium hydroxide by the poz-zolanic reaction, but the presence of chlorides provided by the GWaffected the pore solution and the hydration products of the cementwith the decrease of the compressive strength.

2:20 PMParticle size modifications during cement hydrationF. A. Cardoso, M. A. Cincotto, V. M. John, R. G. Pileggi*, University of SãoPaulo, Brazil

This paper evaluates the changes of particle size distribution (PSD)during hydration of diverse cement materials. Dilute aqueous sus-pensions (≈1g/L) of Portland and calcium aluminate cements wereanalyzed by laser diffraction within a closed loop system at 30-minuteintervals for few hours. The high early-strength sample presented thefastest and most significant increase of particle size among the Port-land products analyzed, whereas the blast-furnace slag / Portlandblended cement remained almost unchanged during the 6-hour test-ing period. The calcium aluminate cement displayed a slight decreaseof mean particle size in the first hour followed by intense formation

of larger particles. Therefore, most of the materials underwent coars-ening of PSD as hydration proceeded, but the kinetics of modifica-tion and the size range of particles being “consumed” and formedvaried according to the cement type.

2:40 PMMicrometer-scale 3-D shape characterization of eight cements:Particle shape and cement chemistry and laser diffractionE. J. Garboczi*, P. E. Stutzman, NIST, USA; S. T. Erdogan, Middle EastTechnical University, Turkey; X. Nie, Exa Corp., USA

Eight different portland cements were imaged at Brookhaven Na-tional Laboratory using X-ray computed microtomography at a voxelsize of about 1 micrometer per cubic voxel edge. The particles rangedin size roughly between 10 and 100 micrometers. The shape of indi-vidual particles was quantified using spherical harmonic analysis.The particle shape difference between cements was small but signifi-cant, as judged by several different quantitative shape measures. Itwas found that the average shape of cement particles seemed to de-pend on the volume fractions of alite and belite making up the ce-ment powder. It is shown that the non-spherical particle shape of thecements strongly influenced laser diffraction results in the sieve sizerange of 20-38 micrometers.

3:00 PMShape comparison between 0.4 - 2.0 and 20 - 60 micrometercement particlesE. J. Garboczi*, NIST, USA; S. T. Erdogan, Middle East Technical University,Turkey; L. Holzer, Empa, Switzerland; R. J. Flatt, Sika Technology AG,Switzerland; J. W. Bullard, NIST, USA

The shape of cement particles can affect the properties of cementpaste at early ages, via specific surface area (reaction) and setting(percolation). Does cement particle shape depend on particle size?For the same cement, we used X-ray computed microtomography toexamine the 3-D shape of particles in the 20-60 micrometer sizerange, and a focused ion beam technique to examine the 3-D shape ofcement particles found in the 0.4-2.0 micrometer size range. Withinexperimental uncertainty, the smaller size class particles tend to be abit more prolate than the larger size class. The effect on early-age hy-dration and setting were approximately assessed using the Virtual Ce-ment and Concrete Testing Laboratory. The two sets of real particleshapes have, within numerical uncertainty, a degree of hydration atset that is different from spherical particles but similar to each other,indicating that their small average shape difference probably does nothave a large effect on cement hydration and setting.

3:40 PMCharacterization of Ottawa sand: Optical and scanning electronmicroscopy, X-ray tomography and diffraction, andnanoindentationE. J. Garboczi*, NIST, USA; S. T. Erdogan, Middle East Technical University,Turkey; G. Lespinasse, A. Forster, P. Stutzman, NIST, USA

Computational materials science models for concrete have to bebased on careful characterization of cement and aggregates. We studya sample of Ottawa sand (North American standard sand). Particleshape and size were acquired via X-ray computed microtomography,sieve analysis, microscopy and image analysis, and laser diffraction.The average length to width ratio of the Ottawa sand investigated wasabout 1.29. We measured mineralogy via quantitative X-ray diffrac-tion (QXRD), finding almost pure alpha quartz, and used the QXRDresults for average crystallite size, 114 nm, to help interpret elasticmoduli information, obtained via instrumented nanoindentation atthe individual grain level. Results for the Young’s modulus are E = 110GPa (6 GPa) (assumed Poisson’s ratio of 0.18), which is significantlylarger than the results obtained by a simple isotropic average of theelastic moduli tensor of alpha quartz, E = 94 GPa.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 81

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania82

4:00 PMUsing Hydrogen/Deuterium Exchange to Determine the C-S-HComposition and Density and the Nanoscale Calcium HydroxideDistribution in Cement PastesA. J. Allen*, National Institute of Standards and Technology, USA; J. J.Thomas, H. M. Jennings, Northwestern University, USA

The large difference in neutron scattering contrast between hydrogenand deuterium provides a powerful tool for characterizing cementhydration products. Results from H2O/D2O and CH3OH/CD3OHfluid exchange experiments have allowed the composition, water con-tent, and density of solid C-S-H nanoparticles to be accurately meas-ured without drying. Results for OPC, C3S, and CaCl2-acceleratedC3S pastes are all similar, indicating that the C-S-H nanoparticles arecompositionally uniform across these systems, whereas C-S-H in al-kali-activated slag paste has a lower water content and higher density.Another application of contrast variation is to adjust the H2O/D2Oratio of the pore fluid such that the C-S-H scattering contrast goes tozero. The observed scattering then arises from Ca(OH)2. These exper-iments indicate that a small amount of nanoscale Ca(OH)2 coexistswith C-S-H gel, and that CaCl2-acceleration increases nanoscaleCa(OH)2.

4:20 PMInitiation of Alkali-Silica Reaction by Potassium Acetate SolutionL. Ai, MetaMateria Partners, USA; L. J. Struble*, University of Illinois, USA

Potassium acetate deicing solution appears to cause alkali-silica reac-tion in concrete containing reactive aggregate. Mortar bars immersedin concentrated potassium acetate solution exhibit quite high expan-sion levels due to alkali-silica reaction. A high pH is generally consid-ered to be necessary to initiate this reaction. The pH of potassium ac-etate deicing solution increased from about 10 to above 14 when thesolution is mixed with a small amount of calcium hydroxide. Experi-ments were performed to understand the reason for this increase.There was no formation of a precipitate that might explain such anincrease in pH. Experimental results suggest that the high pH may bedue to a high hydroxide ion activity coefficient, although model cal-culations of activity coefficient do not support this explanation.

4:40 PMAlkali-silica reaction in asphalt mixtures exposed to potassiumacetate deicing solutionA. Apeagyei, L. J. Struble*, W. Buttlar, University of Illinois, USA

Asphalt mixtures were tested to determine whether alkali-silica reac-tion occurs in asphalt containing reactive aggregate and calcium hy-droxide is exposed to potassium acetate deicing solution. Some mix-tures contained Ottawa sand as a non-reactive aggregate and somecontained fused silica as a reactive aggregate. Mixtures were condi-tioned in water, sodium hydroxide solution, or potassium acetate so-lution saturated with calcium hydroxide at 80 degrees C for 7 days.Evidence of alkali-silica reaction was observed in some mixtures con-taining the fused silica: gel formation occurred in mixtures condi-tioned in the potassium acetate plus calcium hydroxide solution, ex-pansion and surface cracking occurred in mixtures that wereconditioned in the sodium hydroxide solution, and fracture energydecreased significantly in mixtures conditioned in either the sodiumhydroxide or the potassium acetate plus calcium hydroxide solution.

5:00 PMMicrostructure and Performance of Fly Ash Sinking Beads inCementitious SystemH. Li*, D. Xu, S. Feng, N. Liu, B. Shang, College of Material Science andEngineering, Xi’an University of Architecture & Technology, China

Fly ash is a typical pozzolanic material which contains a lot of finesinking beads. The microstructure and performance of fly ash sinkingbeads in cementitious material system was investigated. It was foundthat most of sinking beads were hollow and containing small spheres,

called plerospheres. To release these plerospheres out of the externalshell, fly ash was superfine ground by different grinding facilities,comprising ball mill, vibrating mill and vertical roller mill. The ex-periment results show that the Vibrating mill and the roller mill aresuitable for fly ash grinding with better pulverizing effects. The finefly ash with a mean particles size of no more than 6 microns, couldplay the same role as silica fume in cementing mortars, and resultedin about 40% increase in strength compared with the mortars blend-ing with original fly ash.

Materials & Systems: Glass and OpticalMaterials

ACerS Alfred R. Cooper Session and Award:Performance Stability of Glass ProductsRoom: 334Session Chair: Prabhat K. Gupta, The Ohio State University

2:20 PMChemical Stability of Clean and Functionalized Glass Surfaces(Invited)C. Pantano*, Pennsylvania State University, USA

Physical and chemical adsorption phenomena at glass surfaces medi-ate many important properties including chemical durability,strength, friction, wetting and adhesion. Although the composition ofthe glass and reactivity of the environment are primary factors deter-mining the reactivity/stability of the surface, the processing that leadsto creation of the glass and its surface can also play a role. In somecases, this is due to effects of processing on surface composition,while in others it is due to fictive temperature/structure effects. Wehave used both laboratory and manufactured glass fibers and flatglasses, and a variety of surface sensitive techniques, to understandthe mechanisms through which composition and processing influ-ence the surface reactivity of multicomponent glasses. Selected as-pects of these studies will be exemplified; the effects of surface modi-fication with organo-silanes and polymer thin films will be included.

3:00 PMNano-Architecture in Glasses with a Femtosecond Laser (Invited)K. Hirao*, Kyoto University, Japan

The nonlinear interaction between single crystals, glasses or polymersof transparent materials and femtosecond laser called non-linearmultiphoton effect was studied. The various nano or microstructurechanges caused by this effect has guided the internal modification in-side materials, such as densification, valence reduction of active ions,new crystal precipitation and so on. Such an ultrashort pulse laser ef-fect of transparent materials was useful for fabrication of photonicdevices. In view of our findings, the advantage of femtosecond lasercombined with liquid crystal modulator is also introduced to makethree-dimensional nano-architecture in materials.

4:20 PMSub-Tg Surface Relaxation in Glasses (Invited)M. Tomozawa*, Rensselaer Polytechnic Institute, USA

Glasses usually do not exhibit relaxation below their glass transitiontemperatures but some exceptions are known to exist. Surface relax-ation is one such exceptional phenomenon. A small quantity of watercan enter easily into a glass surface during its heat-treatment and re-duce its viscosity and accelerate its relaxation kinetics. This can influ-ence surface-sensitive glass properties such as mechanical strengthand chemical durability. FTIR measurement was used to determinewater diffusion depth profile and surface fictive temperature profileinto silica glass. The results demonstrated; 1) oxide glasses can exhibitsurface relaxation at far lower temperatures than the glass transitiontemperature, 2) not only water vapor pressure in the atmosphere but

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 82

Mo

nd

ay P

M

www.matscitech.org 83

also glass sample size and shape can affect the surface relaxation ki-netics and 3) molecular water, rather than hydroxyl water, appears toaccelerate the glass relaxation.

5:00 PMDimensional Stability of Glass Display Panels (Invited)D. C. Allan*, Corning Incorporated, USA

We review the role of glass dimensional stability in the context of theLiquid Crystal Display industry. Dimensional stability plays two rolesduring the processing of large panels: at processing temperatures thepanels can sag or flow at temperature, leading to permanent deforma-tion that can interfere with subsequent processing steps, and secondlythe glass at elevated processing temperatures can also shrink (com-pact), leading to misalignment of LCD features and possible failure ofdisplay pixels. These effects are responses to different driving forcesacting on the non-equilibrium glass structure as it evolves toward itsequilibrium at processing temperatures. We discuss these effects fromthe point of view of glass fundamentals and describe attempts tomodel them.

Materials & Systems: InternationalSymposium on Innovative Processing andSynthesis of Ceramics, Glasses andComposites

Mechanism/Kinetics of ProcessesRoom: 336Session Chair: Tomoko Sano, US Army Research Laboratory

2:00 PMMechanically Driven Amorphization and Bulk NanocrystallineSynthesis of Ultra-High Temperature CeramicsH. Kimura*, National Defense Academy, Japan

This article reports the mechanically driven amorphization and thebulk nanocrystalline synthesis of ultra-high temperatureceramics(UHTCs) such as B4C, SiC, ZrB2 and B4C-SiC. A model ex-periment with a planetary ball mill is carried out to provide a processcontrol methodology of the solid state amorphization of covalent ce-ramics by mechanical milling. The solid state amorphization followsthe linear chemical reaction as a function of impaction event numberN, d(Vf-V)/dN = -k(Vf-V) where Vf and V is the amorphous volumeat the final and intermediate stage respectively. The constant k isfound to increase with decreasing powder weight and temperature,and depend on composition and reaction site. The pulse electric cur-rent consolidation is used to obtain the full densification ofnanocrystalline B4C at a relatively low temperature using the amor-phous powder. The mechanical characteristics of nanocrystallineUHTCs will be reviewed with the reference of the crystallite size.

2:20 PMTemplated Grain Growth for Tailoring Novel MicrostructureCompositesR. J. Pavlacka*, G. Messing, Pennsylvania State University, USA

Microstructure composites are single phase ceramics that utilize mul-tiple microstructure features in the same composite to obtain uniqueproperty combinations. Textured-equiaxed microstructure compos-ites with fine spatial control of textured regions are fabricated in thealumina system using liquid phase assisted templated grain growth toachieve texture in situ. A variety of composites connectivities, includ-ing 1-3, 2-2, and 0-3, will be demonstrated. Sintering behavior wasanalyzed using electron microscopy and dilatometry to understandhow composite design affects the co-sintering of different mi-crostructure regions. Unique fracture behavior, particularly the non-catastrophic failure mode, is highlighted.

2:40 PMTi3SnC2 ternary nanolaminate carbide synthesis by hot isostaticpressingN. Ouabadi, V. Gauthier-Brunet, T. Cabioc’h, M. Jaouen, S. Dubois*,Laboratoire PHYMAT, France

We recently report on the synthesis of Tin+1SnCn ternary carbide byhot isostatic pressing starting with titanium, tin and carbon powders[1]. In addition to the already known Ti2SnC compound, a newTi3SnC2 phase is formed (a=0.31366 nm and c=1.8650 nm). In anext step, formation mechanisms are studied. It is demonstrated thatTi3SnC2 phase is formed provided that Fe is added to a Ti:Sn:C reac-tant mixture. 3Ti:Sn:2C:0.6Fe (at. %) powders were then thoroughlymixed in order to reproduce the synthesis conditions of the HIPtreatment. Dilatometry and X-ray diffraction experiments were per-formed at different temperatures in order to indentify the intermedi-ate phases. TixSny, FexSny and TiCx are the main phases present be-fore Ti3SnC2 formation. At 1100°C, a (Fe+Sn) liquid phase appears,the intermediate solid phase can thus dissolve, and Ti3SnC2 phasecan precipitate from the melt. [1] S. Dubois, T. Cabioc’h, P. Chartier,V. Gauthier, M. Jaouen, J. Am. Cer. Soc., Vol. 90 (8), 2642 (2007).

3:00 PMComparison of Slip Cast to Hot Pressed Boron CarbideT. Sano*, E. S. Chin, US Army Research Laboratory, USA

To explore processing techniques, two slip cast techniques were usedto form boron carbide (B4C) compacts. One set was slip cast and sin-tered, and the other was slip cast, sintered, and hot isostaticallypressed (HIP). The HIP process increased the density of the slip castB4C. The microstructural and mechanical characterizations of thetwo sets of slip cast B4C were conducted to compare the material withthe conventional hot pressed (HP) B4C. Microstructural characteri-zation by transmission and scanning electron microscopy of both setsof slip cast B4C showed graphite inclusions and more growth twinsthan in the conventional HP B4C. Despite the higher density ofgraphite inclusions, dynamic uniaxial compression tests on both slipcast B4C showed comparable compressive strength to the conven-tional HP B4C. The fracture mode for both slip cast B4C was brittletransgranular cleavage, with some cleavage surfaces showing twins.The effects of processing technique on the microstructure and me-chanical behavior will be discussed.

3:40 PMSintering and Cristobalite Transformation in Fused SilicaCompactsC. Bae*, D. Kim, J. W. Halloran, University of Michigan, USA

The sintering of fused silica compact and the transformation tocristobalite is examined for refractory grade silica powders with andwithout cristobalite nucleation agents. Sintering shrinkage is deter-mined with dilatometry. We report the transformation kinetics offused silica studied by quantitative X-ray diffraction (QXRD). In theabsense of cristobalite seeds, the transformation is preceded by an in-cubation time which is apparently an activated process with an activa-tion energy of 720.64 kJ/mole. Kinetic analysis is used to determinetime exponent, nucleation, and growth rates for samples with andwithout nucleating agents. The relation between densification, trans-formation, and microstructure after sintering is reported, and relatedto the physical properties of silica investment casting molds and cores.

4:00 PMRole of Green Body Strength on the Development of RapidHeating Cycles for Thermal Binder RemovalS. J. Lombardo*, R. Sachanandani, University of Missouri, USA

In previous work, we have developed an algorithm based on varia-tional calculus for determining the minimum time heating cycle

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 83

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania84

(MTHC) for thermal binder removal from green ceramic compo-nents. The MTHC depends strongly on the pressure and temperatureat which the green body fails. This paper presents both experimentaland modeling results relating the heating schedule and the condi-tions at which the green body fails. The results are then used to clar-ify the interplay between green body size, heating rate, and samplefailure observed in the thermal removal of binder from green ceramicbodies.

4:20 PMSupercritical Extraction of Binder from Green Multilayer CeramicCapacitorsS. J. Lombardo*, K. Krishnamurthy, University of Missouri, USA

Supercritical extraction has been proposed for a number of years asan alternative to the thermal removal of binder from green ceramiccomponents, although primarily from ceramics formed by injectionmolding mixes containing low molecular weight organic compounds.In this work, we examine supercritical extraction for two binder sys-tems used to fabricate multilayer ceramic capacitors with barium ti-tanate as the dielectric. Depending on the constituents in the binderblend, half of the total organic loading can be removed in as little asthree hours. Upon depressurization from supercritical conditions,however, defects within the components may arise. The mechanismand origin of such defects are discussed, and a transport model is de-veloped to describe the pressure distribution within the green bodyduring depressurization. This pressure distribution can then be usedto determine the normal and shear stresses within the component.

4:40 PMPhotonic Machining of CeramicsA. N. Samant*, N. B. Dahotre, University of Tennessee, USA

Photonic machining of ceramics was investigated by using a pulsedNd:YAG laser. The laser parameters were varied in different combi-nations for a well controlled machining and several number ofpulses were chosen to machine blind cavities of various depths andalso a cavity through the entire thickness of different ceramics. Amachining model that was developed took into account the thermaleffects for melting the material, vapor pressure effect for expellingout the molten material and the effect of surface tension in reducingthe expelled depth .The model also considered the transient effect ofde-focusing of laser beam because of the variation in machineddepth as function of material expelled during machining, thus esti-mating the melt depth during each pulse more precisely. The devel-oped model would be a convenient tool for advance prediction of thetotal thermal energy and time necessary for machining desired mate-rial depth.

5:00 PMThermodynamic Modeling of Nd:YAG SinteringJ. E. Saal*, A. J. Stevenson, G. L. Messing, Z. Liu, Penn State University, USA

Neodymium-doped yttrium aluminum garnet (Nd:YAG) is a widelyused laser-emitting material, with advances in recent years producingpolycrystalline Nd:YAG having properties comparable to single crys-tals. A fundamental understanding of the processing of Nd:YAG willenable further improvements. To that end, the phase equilibria dur-ing Nd:YAG sintering is examined by a combined first-principles/thermodynamic modeling approach. The CALPHADmethod is used to describe the Al2O3-Nd2O3-SiO2-Y2O3 pseudo-qua-ternary system and its subsystems. SiO2 is included as it is often usedas a sintering aid in Nd:YAG processing. First-principles calculationsare used to provide thermochemical data for several phases in thesystem, including Nd:YAG. The resulting thermodynamic model isthen used to describe the phase equilibria during sintering, with pre-dictions on how the system behaves at different temperatures andcompositions.

Nanotechnology: Controlled Processing ofNanoparticle Structures and Composites

Nano-enabled Structure-Property RelationshipsRoom: 408Session Chair: Tom Hinklin, Ceramatec

2:00 PMComparison of Different Processing Methods and Impact ofMWNT Dispersion in Polymer NanocompositeR. Thillaiyan, C. Brinson*, S. Pujari, K. Kasimatis, W. Burghardt, J. Torkelson,Northwestern University, USA

Dispersion of carbon nanotube (CNTs) in polymer has been a chal-lenge for more than a decade. In this research we try to address thisissue by dispersing MWNT in polypropylene using continuousprocesses such as solid state shear pulverization and melt mixingmethods. In this presentation, we will discuss about how the MWNTdispersion influence on thermo-mechanical, rhelogical and electricalproperties. Dispersion of MWNT was studied by scanning electronmicroscope and crystallization kinetics. We correlate the dispersionwith mechanical, rheological and electrical properties. Interesting re-sult in this research is that the highly dispersed MWNT shows bettermechanical and thermal properties but the rhelogical and electricalproperties are lower. This presentation will explain the mechanism ofproperty improvement by dispersion of MWNT.

2:20 PMTailored Dispersion and Organization Through BrushModification of Nanoparticles (Invited)L. Schadler*, D. M. Dukes, B. C. Benicewicz, Y. Li, Rensselaer PolytechnicInstitute, USA; S. K. Kumar, P. Akcora, Columbia University, USA

Controlling nanoparticle dispersion and organization is critical totailoring the properties of polymer nanocomposites. By graftingpolymer chains to nanoparticles using RAFT polymerization andvarying the graft density from .05 to .5 chains/nm2 and the molecularweight from 5,000 to 150,000 g/mole, we are studying the matrix/par-ticle wetting behavior and particle dispersion. Dynamic light scatter-ing indicates the existence of stretched brush and mushroom brushregimes. We have found that the separation distance between parti-cles can be tailored through the manipulation of grafted density andmolecular weight, allowing for ordered distributions of nanoparti-cles. In addition, under very specific immiscible conditions, strings ofparticles and lamellar organization of particles occurs due to a bal-ance between attractive polymer/polymer interactions and repulsiveparticle/polymer interactions. Finally, examples of the impact of tai-lored dispersion on properties will be discussed.

3:00 PMSeeding Effects on the Microstructure of SiC Synthesized fromMesoporous C-SiO2 NanocompositesK. Wang*, H. Wang, Y. Cheng, Monash University, Australia

Mesoporous C-SiO2 nanocomposites were infiltrated with polycar-bosilane (PCS) which is a preceramic precursor for silicon carbidenuclei. Different silicon carbide nanostructures were synthesized bycarbothermal reduction of mesoporous C-SiO2 nanocomposites viadifferent heat treatments. X-ray diffraction, scanning electron mi-croscopy, transmission electron microscopy, and nitrogen adsorp-tion-desorption analysis were used to characterize C-SiO2nanocomposites and SiC products. The major morphology formedfrom the mesoporous C–SiO2 nanocomposites without PCS infiltra-tion was nanoparticles, while nanofibers dominated in the productsof PCS-infiltrated compositions. The results indicate that the con-version of PCS into SiC nuclei in mesopores prior to carbothermalreduction has facilitated the formation of SiC nanofibers. Thereforeinfiltration of seeds into mesopores of C–SiO2 precursors appears to

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 84

Mo

nd

ay P

M

www.matscitech.org 85

be an effective means of accelerating the reaction and controllingSiC nanostructures.

3:40 PMNanoparticle / polymer composite fluid for reversible colloidaljoining (Invited)H. Abe*, J. Noma, M. Naito, Osaka University, Japan

Ferromagnetic Fe nanoparticles have been synthesized by Arc plasmamethod. By utilizing thermal pinching effect of arc plasma, their sizeand morphology were controlled. In addition, our surface engineer-ing of chemical vapor surface modification allows covering the metal-lic surface with hydrophobic modified thin oxide. The resulting air-stable-metallic nanoparticles have led to novel materials for thepreparation of efficient magneto-rheological fluid (MRF). High load-ing of the nanoparticles were achieved into conventional lubricatingpolymer, and large magneto-rheological response have been firstlyprobed in the nanoparticle dispersed system. The relations among thenanoparticle size and morphology, surface property and MR effectwill be presented in detail. The nanoparticle dispersed MRF can beutilized as a reversible colloidal joining material for human-friendlycompact actuators. The performance of prototype nano-MRF devicewill be reported as well.

4:20 PMModification of ceramic fabric with carbon nanotubes fortoughened compositesA. Rider*, Defence Science and Technology Organisation, Australia; N. Brack,La Trobe University, Australia; E. Yeo, Defence Science and TechnologyOrganisation, Australia

A scaled-up chemical vapour deposition (CVD) reactor has beenused to coat large areas of ceramic fabric with multi-walled carbonnanotubes (MWCNTs) for the production of ceramic-epoxy com-posites. MWCNTs were grown in a thick forest perpendicular to thefibre length to provide out of plane reinforcement in the composite.Microscopic characterisation of the composites revealed high con-centrations of well dispersed MWCNTs in the resin rich areas be-tween the ceramic fibres. Plasma treatment of the MWCNT coatedfabrics facilitated better resin wetting, which was characterised by in-creased carbonyl group concentrations measured with XPS. Mode Itests on thin laminates showed almost a doubling of fracture tough-ness for the carbon nanotube coated fabric compared to the uncoatedceramic fabric. These results suggest that the MWCNTs can improvethe fracture toughness of ceramic-polymer composites when growndirectly onto the ceramic fibres.

4:40 PMEffects of a Bio-inspired Interfacial Modification on the Propertiesof Polymer Matrix NanocompositesL. M. Hamming, P. B. Messersmith, C. Brinson, S. Watcharotone*,Northwestern University, USA

Two of the most important variables influencing a nanocomposite’sproperties include the quality of the interphase and dispersion of thenanoparticles. We performed surface-initiated polymerization (SIP)on titania nanoparticles with an initiator modeled after 3,4-dihy-droxy-L-phenylalanine (dopa), an amino acid that is highly concen-trated in mussel foot adhesive proteins. Dopa has been shown to ad-here robustly to a variety of surfaces even in an aqueousenvironment. Our biomimetic modification led to composites with ashift in the glass transition temperature (Tg) towards higher temper-atures. By contrast, unmodified nanoparticles led to a shift towardslower temperatures. We further discovered that better dispersionleads to a more pronounced Tg shift. As Tg is considered a measure ofinterfacial interaction in nanocomposites, this work highlights anovel technique for increasing the reinforcement capability ofnanoparticles.

5:00 PMEffect of Particle Surface Area on the Properties of HydroxyapatiteNanocomposites (Invited)J. Kaur*, M. L. Shofner, Georgia Institute of Technology, USA

Nanoparticles have different attributes like size, surface area, sur-face chemistry etc. which have been varied to understand the effecton the nanocomposite properties. This study looks at the inherentcontribution of the surface area of nanoparticles on the propertiesof the nanocomposites. Hydroxyapatite nanoparticles of varyingsurface area were prepared by reverse microemulsion followed bycomposite preparation with polycaprolactone matrix via solutionprocessing. The thermal properties were observed to be almost in-dependent of surface area. Surface area was found to influence theviscoelastic properties with higher surface area particles reinforc-ing the composites at all temperatures compared to lower surfacearea particles, which showed reinforcement only above the glasstransition temperature. These results suggest that the reinforce-ment can be scaled with surface area and it may be used as a pa-rameter to modify existing models concerning nanocompositeproperties.

Nanotechnology: Nanotube-Reinforced MetalMatrix Composites

Processing Techniques for Nanotube-ReinforcedMMCs IIRoom: 409Session Chair: Indrajit Charit, University of Idaho

2:10 PMCarbon Nanotube Reinforced Aluminum Composites via ThermalSpray (Invited)A. Agarwal*, Florida International University, USA

This talk will focus on the synthesis of carbon nanotubes (CNTs) re-inforced aluminum composites using variety of thermal spray tech-niques viz. plasma spray, HVOF and cold spray. Key processing issuessuch as powder pretreatment and CNT dispersion in the spray de-posited composite will be discussed. Thermodynamic and kinetics ofinterface between nanotube and metal matrix will be elucidated. Me-chanical properties of CNT reinforced aluminum composites willalso be discussed.

2:50 PMMultiwall Carbon NanoTube Reinforced Chromium CarbideComposite Coating for Wear ResistanceV. Singh*, R. Diaz, University of Central Florida, USA; K. Balani, A.Agarwal, Florida international university, USA; S. Seal, University of CentralFlorida, USA

Cr3C2 coating is widely used in tribology because of its high wear re-sistance and hardness at higher temperatures with soft binder ma-trix(25% NiCr). An attempt has been made to further enhance themechanical properties of Cr3C2 coatings by reinforcing MWCNTusing plasma spray technique.Microstructure of the plasma sprayedCNT reinforced Cr3C2 coatings were characterized and their mechan-ical properties were assessed using micro Vickers and nano indenta-tion technique. The composite coatings were also subjected to wearand friction test. CNT reinforcement certainly improved the hardnessand the friction coefficient of the coating. Elastic moduli of coatingswere determined by nano indentation technique. Cr3C2 reinforcedwith 2 wt% CNT showed hardness ~ 1175±60 VH, friction coefficient~0.654 and elastic modulus~ 304.5 ±29.2 GPa. Mechanisms to im-prove wear resistance and hardness with CNT reinforcement are dis-cussed. CNT reinforcement increases the wear resistance by intersplatbridging.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 85

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania86

3:40 PMApplication and Potential of Adding Nanotubes to AluminumUsing Friction Stir Processing (Invited)L. Johannes*, NASA - Johnson Space Center, USA

Single-walled carbon nanotubes (SWCNTs) and multi-walled carbonnanotubes (MWCNTs) were added to aluminum using friction stirprocessing (FSP). The survival of the SWCNTs will be discussed withrespect to the thermal and stress cycles involved with friction stir pro-cessing. Raman spectroscopy and SEM results are presented. Com-parisons will be made to a similar study performed with multi-walledcarbon nanotubes (MWCNTs) and various methods of the insertionof nanotubes and other nano-particles through FSP will be discussed.

4:20 PMMulti-Walled Carbon Nanotube Reinforced Metal MatrixComposites via Ball Milling TechniqueT. Shrestha*, I. Charit, University of Idaho, USA

Multi-walled carbon nanotubes (MWCNT) are incorporated into themetal matrices (Sn-Ag and Al) via standard powder metallurgy tech-niques. The microstructure of bulk samples are studied using scan-ning electron microscopy. Mechanical properties of the bulk samplesare evaluated using microhardness and impression creep tests. Theproperties of nanotube composites are found to be much better thanunreinforced metals. Mechanical properties of the nanotube compos-ites are found to increase as a function of nanotube volume fraction.Further, differential scanning calorimetry (DSC) experiments wereperformed to understand the reaction kinetics of carbide formationin the MWCNT-reinforced composites.

Processing & Product Manufacturing:International Symposium on Ceramic MatrixComposites

Composite Processing and Characterization IRoom: 413Session Chair: Kwang Bo Shim, Hanyang University

2:00 PMCharacteristics of Graphene Layers transformed from CarbonNanotubes by the pulsed electric current assisted sintering process(Invited)K. Shim*, Hanyang University, South Korea

The multi wall carbon naotubes (MWCNT) as starting materials weresynthesized by the catalytic chemical vapor deposition method inwhich the CH4 and/or C2H2 was converted into the MWCNT at700oC in the presence of Fe catalyst. The pulsed electric current as-sisted sintering process transformed the MWCNTs into the micro-sized graphite nanofilms depending on the various process condi-tions. The resulting graphite films are crystalline with single and/oragglomerated layers. The transition mechanism from the MWCNTsto the graphite nanofilm is proposed that the tubular CNT initiallybroke down and then stretched away like the film. Taking into ac-count the rapid and simple operation features of the pulsed electriccurrent assisted sintering process, it could be suggested that thisprocess shows great potential for graphite film synthesis from thecommercially available CNT in a large scale.

2:40 PMThin Coatings of ZrB2-SiC Composites for Oxidation Protectionof C-C CompositesE. L. Corral*, R. E. Loehman, Sandia National Laboratories, USA

The development of next generation hypersonic flight vehicles re-quires new thermal protection system (TPS) materials. The struc-tures of these vehicles are primarily manufactured using C-C com-posites that oxidize in air at low temperatures (>500°C). Our TPS

development efforts focus on developing superior coatings ofZrB2-SiC composites to provide oxidation protection for C-Ccomposites. Our approach combines pretreatments of C-C com-posites to create continuous and adherent UHTC coatings from in-filtrated pre-ceramic polymers. Our protective coatings were eval-uated for thermal-shock performance up to 2600-°C, at theNational Solar Thermal Testing Facility, using controlled cold-wallheat-flux profiles reaching a maximum of 680-W-cm-2, and surfacetemperatures as high as 2600-°C. Sandia National Laboratories is amultiprogram laboratory operated by Sandia Corporation, a Lock-heed Martin Company, for the U.S. Dept. of Energy under ContractDE-AC04-AL85000.

3:00 PMGraphite Formation in Carbon from Wood PrecursorsM. T. Johnson*, K. T. Faber, Northwestern University, USA

Graphite, due to its high thermal conductivity, is attractive for usein thermal management applications. Carbon derived from woodprecursors provides a porous scaffold into which highly conduc-tive materials may be added. A method for facilitating graphiteformation at low temperatures is investigated. Two graphite-pro-moting approaches are taken: the catalytic formation of graphitepost-pyrolysis and the use of atmospheric controls to prevent theformation of hard, poorly graphitizing carbon during pyrolysis.Amorphous carbon is processed in the presence of a metallic-cat-alyst (CuO) in a nitrogen atmosphere to 1500°C. Catalyzed sam-ples are also prepared in a similar fashion with CuO, but in thepresence of a hydrogen-containing atmosphere, as hydrogen is be-lieved to hinder cross-linking in carbon made from organic pre-cursors. The degree of graphitization is then measured using XRDof powdered specimens. X-ray results show partial graphitizationof amorphous carbon samples processed with 5wt% Cu at1500°C.

3:20 PMThermal and mechanical properties of carbon char formed bypyrolysis of polymer compositesM. A. Makeev*, J. Lawson, D. Srivastava, NASA Ames Research Center, USA

We report on our results of molecular dynamics simulation study ofthermal and mechanical properties of char obtained by high-tem-perature pyrolysis of model polyethylene. A solid-state char struc-ture was naturally formed in the process of hydrogen removal at el-evated temperatures. The details of dynamics of the process will beaddressed in this presentation by invoking the kinetic-rate theoryarguments. Further, we will discuss the microstructure of char andestablish (micro-) structure-property relationships of model char.Thermal conductivity (TC) of char samples was investigated in arange of temperatures from 50K to 500K and the thermal expan-sion coefficient was computed. The behavior of TC with tempera-ture will be discussed by addressing details of microstructure andvibrational spectra of char in the corresponding temperature range.The mechanical properties of char will be reported on in this talkand compared with those of amorphous carbon, obtained by differ-ent means.

4:00 PMInvestigation on A/W -phologopite glass-ceramic composite bypowder sintering methodA. Faeghi-Nia*, tabriz university, Iran

The aim of this investigation is producing in-situ form of phlogopitecrystals as a reinforcing agent during sintering of apatite-wollastoniteglass-ceramic , in order to increase the fracture toughness.Frites ofA/W glass composition and phlogopite glass composition prepared,mixed together for producing composites ,For this purposeHSM,DTA in different heating rate and , ,SEM,EDAX, methods usedfor studying of crystallization and sintering of phlogopite - A/W

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 86

Mo

nd

ay P

M

www.matscitech.org 87

composites.Moreover, it was proved that coarse particle of phologo-pite in composites shows better sinterability than fine phlogopite par-ticles in composites.

4:20 PMPreparation and Electrical Properties of Lanthanum-NickelOxides Ceramic Matrix CompositesC. Kao*, H. Cheng, National Cheng Kung University, Taiwan

The precursors of lanthanum-nickel oxides ceramic matrix compos-ites were prepared by chemical coprecipitation. Firstly, lanthanumoxide, and nickel oxide were reacted with nitric acid to obtain the cor-responding nitrates, respectively. Coprecipitation was carried outfrom the appropriate ratios of sodium hydroxide to lanthanum ni-trate and nickel nitrate (La:Ni = 2:1, 1:1, 1:2), respectively. Coprecipi-tates were collected by filtration and drying. The better crystallinity ofthe powder occurred at 1173 K for 10 h as examined by XRD. Cal-cined powder was pressed into a disk then sintered at various temper-atures and times. The sintered bodies were measured for electrical re-sistivity. The dielectric constants for the sintered bodies were alsodetermined.

Processing & Product Manufacturing: Micro-Manufacturing: Material Behavior,Deformation Mechanics, Process Control andApplications

Micro-Manufacturing IIRoom: 410Session Chairs: Marwan Khraisheh, University of Kentucky; SasawatMahabunphachai, Virginia Commonwealth University

2:00 PMSurface modification and nanostructuring of metals usingfemtosecond laser pulsesT. Nakashima*, T. Sano, A. Hirose, Graduate School of Engineering, OsakaUniversity, Japan

We found that unique surface morphology and microstructure areinduced by the irradiation of femtosecond laser pulses on Cu, Al,Pt, and steels. Periodical nanostructure is formed on the surface ir-radiated near the damage threshold. Many defects and unique mi-crostructures are induced in the metal irradiated with the intenselaser pulses. We suggest that these unique features are resultedfrom the rapid cooling rate of the melting layer and high strainrate driven in the solid, which are characteristic of the femtosec-ond laser ablation of metals. Formation mechanism of mi-crostructures in the heat and shock affected zones will be dis-cussed in the talk.

2:20 PMFemtosecond laser-driven shock deformation of single crystalsiliconM. Tsujino*, T. Sano, N. Ozaki, Graduate School of Engineering, OsakaUniversity, Japan, Japan; O. Sakata, M. Okoshi, Japan Synchrotron RadiationResearch Institute / SPring-8, Japan; N. Inoue, National Defense Academy ofJapan, Japan; R. Kodama, A. Hirose, Graduate School of Engineering, OsakaUniversity, Japan, Japan

We investigated crystalline structure and residual stress of singlecrystal silicon deformed by femtosecond laser-driven shock compres-sion. When the femtosecond laser pulse is irradiated, the mechanicalshock wave is driven on the surface and travels into the material.Plastic deformation and phase transition sequentially occur in siliconunder the shock loading. TEM observation and synchrotron XRDanalyses were performed for the femtosecond laser irradiated silicon.TEM observation showed a great deal of defects in the sub-micronsfrom the surface. As the results of synchrotron XRD analyses, the ex-

istence of high-pressure phases was confirmed near the surface.These deformations have never been reported for the recovery exper-iments using the static and the dynamic compressions. The materialdynamics under the shock loading and release will be discussed inthe talk.

2:40 PMResidual Gradient Stress Evolution in Bimaterial MicrocantileverStructures during Thermal Cycling (Invited)I. Lin, K. Fan, S. Huang, A. Gonzalez, K. Zhang, X. Zhang*, BostonUniversity, USA

In this work, a micro heating stage and interferometer were used for in-situ monitoring of the microcantilever beam curvature during thermalcycling.After each thermal cycling treatment, the curvature at room tem-perature changed due a change in the residual gradient stress. From atheory we recently developed, a residual gradient strain profile can be de-rived from the curvatures measured by continuously etching the SiNxlayer of the bimaterial cantilevers. To understand the effect of thermal cy-cling on the evolution of the residual stress gradients, we analyzed meas-urements taken after each thermal cycling treatment. The microstruc-tural evolutions due to thermal cycling in SiNx/Al were studied usingAFM. Grain growth in both the vertical and lateral directions is present.Upon understanding the mechanism behind the gradient residual stressevolution, thermal cycling can be widely used to control the curvature ofbimaterial microcantilever structures to meet specific functions.

3:00 PMShock deformation synthesis of hexagonal diamond from highlyoriented pyrolytic graphiteT. Sano*, K. Takahashi, Osaka University, Japan; O. Sakata, Japan SynchrotronRadiation Research Institute / SPring-8, Japan; M. Okoshi, N. Inoue, NationalDefense Academy of Japan, Japan; K. F. Kobayashi, Fukui University ofTechnology, Japan; A. Hirose, Osaka University, Japan

We synthesized hexagonal diamond directly from highly oriented py-rolytic graphite (HOPG) using femtosecond laser-driven shock wavewithout using catalyst. Femtosecond laser pulses (wavelength: 800nm, pulse width: 120 fs, intensity: 2x10^15 W/cm^2) were irradiatedonto the HOPG surface in air. Crystalline structures inside HOPGafter the laser irradiation were analyzed using synchrotron X-ray dif-fraction and TEM observation. We found that hexagonal diamondstructure existed in the HOPG which was irradiated by the femtosec-ond laser normal to the basal plane. Deformation and phase transi-tion processes will be addressed in the talk.

Processing & Product Manufacturing:Paradigm Shift in the Metals Industry

Paradigm Shift in the Metals Industry IIRoom: 411Session Chair: Charles Parker, Honeywell Aerospace

2:00 PMChallenges and Opportunities in the Iron and Steel Industry(Invited)R. Sussman*, Arcelor Mittal Steel, USA

Abstract Not Available

2:40 PMRecent Trends in Flat-Rolled Stainless Alloys (Invited)J. F. Grubb*, ATI Allegheny Ludlum, USA

The prices of raw materials used to make corrosion resistant alloyshave increased dramatically in recent years. Nickel prices are aboutfivet times what they were six years ago. Molybdenum prices areabout ten times the 2001 price. Since these elements are present in

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 87

Mo

nd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania88

many corrosion resistant alloys, such dramatic changes in materi-als costs have a profound impact on materials costand on materialsselection. However, the choice does not have to be between use oftraditional corrosion resistant alloys and non-resistant alloys.Lower alloy content, corrosion resistant alloys are being developedand the use of older “lean” alloys expanded. Examples provided toillustrate this include: (1) Substitution of type 201 stainless steelfor type 304 stainless steel, (2) Substitution of AL 2003 lean duplexstainless steel for type 316L stainless steel, and (3) Development ofmodern versions of Type 216 stainless steel. The impact of rawmaterials price variability data on costs of selected alloys will bepresented.

3:40 PMLowering Material Cost With High Performance Stainless Steels(Invited)P. Ray*, Carpenter Technology Corporation, USA

As the cost of raw materials increases, metals customers are increas-ingly looking at alternative alloys. Rather than focusing on best per-formance or cheapest initial cost, customers are looking for the bestperformance per dollar. Cost to the customer must be analyzed overthe life of the part. The final cost to the customer can be lowered bydecreasing material, fabrication, maintenance, or replacement costs.Stainless steels represent a classification of alloys with a uniquecombination of properties that can be used as an upgrade to alloysteels or lower cost alternative to titanium or nickel-based alloys.Likewise, existing stainless steels are being modified to reduce criti-cal elements, such as nickel, molybdenum, and cobalt. This presen-tation will present specific examples of new high performance appli-cations for stainless steels in the aerospace and automotiveindustries.

4:00 PMChromium and Hexavalent Chromium (Invited)E. Torsner*, Outokumpu Stainless, USA

Chromium makes stainless steel stainless. Chromium is the activecomponent of many nickel base alloys, chromium- and nickel-plat-ing, and zinc galvanizing. New hexavalent chromium regulation iscausing many to look for other solutions but finding none. Thehexavalent state of the chromium atom is declared carcinogen.OSHA’s new permissible exposure limit PEL for hexavalentchromium is 5 μg/m3, down from 52 μg/m3. The underlying healthstudies mainly concern chromate salts. Hot operations like melting,hot rolling, heat treatment, welding, torching, grinding, and polish-ing create oxides. There are no studies linking cancer to hexavalentchromium oxides or welding of stainless steel. All methods of weld-ing are severely affected. Even worse, Public Citizen and UAW want aPEL of 1μg/m3. A Federal Court decision is not expected until earlyAutumn 2008. A recent study of digested hexavalent chromiumshows cancer in the digestive tract of laboratory animals. There isnow immense public pressure to regulate hexavalent chromium indrinking water.

4:40 PMAerospace Superalloys-The Response to Global Influences(Invited)R. L. Kennedy*, R. A. Jeniski, ATI Allvac, USA

The dynamics affecting the aerospace market for wrought superalloysinclude strong market growth, new and more efficient engines, rawmaterial price fluctuations, cost pressures, offshore producers/cus-tomers and novel new materials. The industry response to these pres-sures will take the form of new equipment and increased capacity,new alloys and process technology development coupled with costand quality improvements. This talk will review many of these initia-tives from an industry-wide perspective.

Processing & Product Manufacturing:Processing, Properties and Performance ofComposite Materials

Metal Matrix Composites - LaminatesRoom: 412Session Chairs: Nikhilesh Chawla, Arizona State University;Jonathan Spowart, United States Air Force

2:00 PMLaminates, anyone? (Invited)K. Chawla*, Univ. of Alabama at Birmingham, USA

Laminates made of one or more type of sheet materials are com-monly observed in nature. Examples from mother nature includenacre, abalone shell, etc. Laminates made of steel have been used tomake Samurai swords. The famous iron pillar of Delhi consists oflaminae of wrought iron. They have been used in industrial practicefor quite some time. Examples include laminated glass for automo-bile windshields and windows for the cockpits of airplane as well ascopper/aluminum and copper/stainless laminates for kitchen uten-sils. More recently, researchers have been investigating multilayeredcomposites consisting of metal/metal and metal/ceramic laminates.In this presentation, I will provide examples of structural laminates innature and various industrial realms. Following this, I will presentsome results from our work on Al/Al Alloy and Al/stainless steel lam-inated made by roll bondng, and Al/SiC nanolaminates made byphysical vapor deposition.

2:40 PMMicrostructural evolution of the interface in laminatedAISI304/high-strength steels during thermomechanical treatmentM. Michiuchi*, S. Nambu, J. Inoue, T. Koseki, The University of Tokyo, Japan

The microstructural analysis of the interface in laminated steel con-sisting of AISI304 austenitic stainless steel and high-strength steel,fabricated by cold-roll cladding and following heat treatment, was ex-amined by energy-dispersive x-ray spectroscopy and orientation im-aging microscopy. The interfacial microstructure of as-rolled steelshowed the bonded boundary of newly-formed surface on the start-ing base steels due to cold rolling, and oxide debris distributed on theinterface. After heat-treatment at 1373 K for 300 s followed by waterquenching, laminated steels showed recrystallized grains in AISI304layer and lath martensitic structure in high-strength steel layer. Crys-tallographic analysis revealed that the lath martensite has the relation-ship (110)martensite//(111)austenite with neighbor austenite grainsin AISI304 layer. The metallographic and crystallographic features ofthe interfacial microstructure in laminated steel are characterized.

3:00 PMLaser In-Situ Synthesis of TiB2-TiC Reinforced CompositeCoating on SteelB. Du*, S. R. Paital, N. B. Dahotre, The University of Tennessee, USA

Laser Surface Engineering (LSE) has been explored for in situ synthe-sis of TiB2-TiC reinforced composite coating on AISI 1010 steel toimprove the hardness and wear resistance of steel. A series of com-posite coatings were made by employing Fe, B4C and Ti as precursor.TiB2 and TiC were found to be the predominant reinforcements. Lat-tice parameters and relative phase fractions have been calculatedbased on the XRD results. Microstructural examination reveals dif-ferent morphologies of TiB2 and TiC: blocky TiB2 crystals and smallparticle and dendrite-shaped TiC. The formation mechanism andmorphologies of the reinforcements were discussed by consideringthe thermodynamic property of Fe-Ti-B-C system as well as the crys-tal structure of TiB2 and TiC. Wear resistance of the composite coat-ing estimated by a pin (WC) on disk wear tester reveals a significantimprovement compared with the steel substrate.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 88

Tues

day

AM

www.matscitech.org 89

3:40 PMPlastic Flow Stability of Ultra-high Strength NanolaminateComposites (Invited)A. Misra*, Los Alamos National Laboratory, USA

Nanolaminate composites synthesized via physical vapor depositionpossess ultra-high strengths and can be deformed to large plasticstrains via room temperature rolling. An overview of the length-scaledependent plastic flow stability of nanolaminates composites will bepresented. The metal-metal systems such as copper - niobium willcompared with metal-nitride such as aluminum – titanium nitrideand metal-metallic glass such as copper – palladium silicide (amor-phous). A symmetric slip model will be presented to account forpreservation of the initial crystallographic relations after large straindeformation. The mechanisms that allow homogeneous co-deforma-tion of metallic glasses, without shear band instability, withnanoscale crystalline layers at high stresses will be discussed. This re-search is supported by DOE, Office of Science, Office of Basic EnergySciences.

4:20 PMInterfacial Bonding Strength and Mechanical Properties of HighStrength Steel and Austenite Stainless Steel Laminated PlatesS. Nambu*, M. Michiuchi, J. Inoue, T. Koseki, The University of Tokyo, Japan

Laminated steel plates which consist of high strength steel andaustenite stainless steel are proposed to obtain high strength-duc-tility combinations. Bonding strength at the interfaces betweenlayers is important to avoid fracture due to delamination. In thisstudy, the bonding strength was investigated by a peel test and theeffect of peel strength on mechanical properties in tensile defor-mation was considered. The laminated steel plates were preparedby a cold-rolling process to obtain relatively weak bondingstrength. The bonding strength was controlled by reduction inthickness and the following heat-treatment. The result of the peeltest demonstrated that the peel strength increased with increasingheat-treatment temperature and time. It was found that the frac-ture profile and elongation were affected by the bonding strengthof interface.

4:40 PMEngineering and Processing for Multi-Layer Clad MetalsL. Chen*, P. R. Goldstein, R. P. Willis, Technical Materials, Inc., USA; K. He,National High Magnetic Field Laboratory, USA

Clad metals, layered metallic composites, play special roles in mate-rials development and applications. Normally, clad metals have twoor three component layers. However, requirements in material func-tions or performance sometimes demand a multi-layer clad metalwith >30 multiple-layers, in which the thickness of each layer can bea sub-micrometer or near nano-scale. It is obvious that designs andengineering of material process are essential to obtain such multi-ple-layer clad metals. After reviews on basic clad metal processes,this paper describes engineering considerations on processes formultiple-layer clad metals. Composite and process design method-ologies are discussed. Examples have been given on Cu/Ti/CuAgmultiple-layer clad metal for active brazing filler alloys, Cu/Nb mul-tiple-layer clad metal for special magnetic application, and Cu/Invarmultiple-layer for thermal expansion controlled electronic packag-ing applications.

Tuesday, October 7, 2008

Keynote & Lectures

Richard M. Fulrath Award LecturesRoom: 403Session Chair: Martin Harmer, Lehigh University

8:00 AMMetal-Organic Chemical Vapor Deposition and Property of HighQuality Dielectric Thin Films (Invited)H. Funakubo*, Tokyo Institute of Technology, Japan

High quality Pb(Zr,Ti)O3 and bismuth layer-structured ferroelectrics(BLSF) films were grown by metal organic chemical vapor deposi-tion. Orientation and the Zr/(Zr+Ti) ratio dependencies of the fer-roelrectricity were revealed from the epitaxial films of Pb(Zr,Ti)O3investigation in addition to the contribution of the non-180 degreedomains. On the other hand, the investigation of the orientation-con-trolled epitaxial BLSF films makes clear the strong crystal anisotropyof the ferroelectricity. Based on the results, a novel composition of(Bi, Nd)4(Ti,V)3O12 with the spontaneous polarization about 60μC/cm2 was discovered. In addition, the thickness degradation- freedielectric characteristic was demonstrated along c-axis having thestack structure of the bismuth oxide and psudoperovskite layers.

8:40 AMPiezoelectric Properties in Textured Ceramics of Bismuth LayerStructured Ferroelectrics (Invited)M. Kimura*, Murata Manufacturing Co., Ltd., Japan

Texture engineering is expected to improve various properties forelectronic ceramics, especially for piezoelectric ceramics. Becausepiezoelectric material properties are closely related to the crystal sym-metry and orientation, the grain orientation is effective to enhancethe piezoelectric properties of ceramics, and these effects clearly ap-pears in materials with large anisotropy, such as bismuth layer struc-tured ferroelectrics (BLSF). Textured ceramics of BLSF have beenstudied since 1970’s, and it was reported that the piezoelectric con-stant or electro-mechanical coupling coefficient are improved drasti-cally by grain orientation. However, limited studies have been carriedout for resonator applications of textured BLSF ceramics. Therefore,we fabricated BLSF textured ceramics by templated grain growth(TGG) method, and studied the relationship between grain orienta-tion and the resonance properties. Then, it was revealed that the tem-perature dependence of resonance frequency is controllable withchanging the texture fraction and cut angle of the textured ceramicsin thickness-shear (TS) mode vibration. High temperature-stability,which has been required for practical resonator applications, can beachieved by controlling texture fraction and cut angle. We will pres-ent piezoelectric properties and their temperature dependence of thetextured BLSF, and their relationship to the grain orientation will bealso discussed.

9:00 AMTeaching “Old” Ceramics “New” Tricks: Nanopatterning ofMultifunctional Ceramics (Invited)V. Dravid*, Northwestern University, USA

Recent years have witnessed a remarkable convergence of physical sci-ences, biology and engineering under the broad umbrella ofnanoscience and nanotechnology. Indeed, there is an obvious synergyamong these apparently disparate disciplines when the length scalesof phenomena and structures approach the nanoscale. This has led tothe emergence of several innovative approaches to pattern and hier-archical arrange intricate nanoscale architecture for functional de-vices and systems - with requisite precision, accuracy and diversity ofmaterials systems. This is helping translate innovations in nano-sci-ence to nano-technology. As an offshoot, such surface patternednanoscale architecture offers unprecedented opportunities to revisit

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 89

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania90

fundamental materials science phenomena, under spatial and dimen-sional constraints. The dimensional constraints (in zero, one or two-dimensions) and spatial constraints (from substrate and/or overlay-ers) of patterned nanostructures flirt with thermodynamics ofconstrained systems on one hand and dynamics of nanoscaleprocesses on the other. The presentation will first cover patterningand lithography down to nanoscale, with an emphasis on multifunc-tional oxide ceramics. In particular, our group is involved in harness-ing fundamental interactions between electrons and scanning probewith substrate, for both lithography and microstructural analysis. Re-cently introduced facile soft electron beam lithography (soft-eBL)scheme is being utilized for making “tailor-made” interfaces and sur-faces for understanding nucleation, growth, shape evolution andstrain effects in surface patterned nanoscale architecture of ceramics.Advanced scanning probe, in-situ and ex-situ electron, ion and pho-ton microscopy, spectroscopy and synchrotron x-ray scattering ap-proaches are being employed to fathom the most intricate details ofthe internal “microstructure” of nanostructures, coupled with inno-vative tools to validate their functional identity and localized proper-ties. It will be argued that multifunctional nanostructures go beyondthe “hype”, and present challenging yet exciting opportunities for syn-thesis-structure-architecture-form-function-performance relation-ships in complex ceramic materials systems.

10:00 AMMicrostructural Design of Dielectrics for Ni-MLCC with Ultra-Thin Active Layers (Invited)Y. Mizuno*, Taiyo Yuden Co., Ltd., Japan

In recent years, multilayer ceramic capacitors with Ni internal elec-trode (Ni-MLCCs) composed of more than 800 dielectric layers ofbelow 1μm thickness have been mass-produced. A deliberate mi-crostructural design of dielectrics must be essential for Ni-MLCCswith considerably thin dielectric layers since the microstructure has adecisive influence on the electrical properties and reliability of Ni-MLCCs. In this study, the influence of raw BaTiO3 (BT) powdercharacteristics, such as particle size and crystallinity, on the mi-crostructure as well as the electrical properties of X7R-type Ni-MLCCs was investigated in the BT-Ho-Mg-Mn system. For theMLCC samples, the dielectric constant at room temperature de-creased with a decrease in the grain size. In particular, the dielectricconstant drastically decreased for the grain sizes of less than 200 nm.On the contrary, the dielectric constant under DC-bias field of morethan 5V/μm increased with a decrease in the grain size. On the otherhand, the dielectric constant without DC-bias field was considerablydependent on the tetragonality (c/a) of the raw BT powder, whereasthe full-width at half maximum (FWHM) had little effect on the elec-trical properties. The samples obtained from the raw BT powder withhigh c/a showed the inhibited grain growth and they consisted of alarge number of core-shell grains having clear domain patterns in thecore region. Accordingly, the sample with high c/a showed high di-electric constant and good temperature characteristics with respect tocapacitance.

10:20 AMC-Sphere Flexure Strength of Bearing-Grade Silicon Nitride Balls(Invited)A. Wereszczak*, Oak Ridge National Laboratory, USA

A “C-sphere” specimen geometry was conceived and developed tomeasure failure stress of bearing-grade silicon nitride (Si3N4) ballscaused by tension at the ball’s surface. The induced method of frac-ture also allows for the study of surface-located strength-limitingflaws in ceramic spheres. A slot is machined into the balls to a setdepth to produce the C-sphere geometry. A simple, monotonicallyincreasing uniaxial compressive force produces an increasing ten-sile stress at the C sphere’s outer surface that ultimately initiatesfracture. The strength is determined using the combination of fail-ure load, C sphere geometry, and finite element analysis. Addition-

ally, the stress field was used to determine the effective area and ef-fective volume of a C-sphere as a function of Weibull modulus thatenable strength-size-scaling. The development of the c-sphere ischronicled here and an example of its use is described involving thetesting of three commercially available bearing-grade Si3N4 ballmaterials.

Arthur L. Friedberg Memorial LectureRoom: 402

10:00 AMHunting the Perovskite Range (Invited)H. U. Anderson*, Missouri University of Science & Technology, USA

I am greatly honored to be chosen to present the 2008 Arthur L. Fried-berg Memorial Lecture. For this lecture I will focus on the applicationof ceramics for use as components in the electrical and energy-relatedindustries. Ceramics are unique in their ability to interact with electricand magnetic fields, and exhibit properties that can vary many ordersof magnitude. These include the dielectric permittivity, electrical con-ductivity, piezoelectricity, magnetic susceptibility, and magneto- andelectro-optics. With this variety of properties, the use of ceramic com-ponents in electronics is so vast that it includes most of the devices andappliances which we encounter and use every day. For example, theelectrical insulating properties allow for the use of materials such asalumina for substrates in integrated circuits as well as high voltage in-sulators (e.g. computers, spark plugs, TV). Electrical energy storagecapabilities have allowed ceramic materials to be integral parts of elec-tronic circuits which require both active component isolation as wellas local power supplies which capacitors provide (e.g. TV, computers,cell phones). A high electronic conductivity allows ceramics to be usedas electrodes as well as resistors for a wide range of applications. Piezo-electric properties allow ceramics to serve as transducers for manyeveryday applications (e.g. ultrasonic imaging and smoke detectors).And the ability of zirconia to display a high oxygen ion conductivityhas enabled a rapidly growing list of applications such as oxygen sen-sors (every automobile has one), oxygen separations membranes andelectrolytes for solid oxide fuel cells. All of these applications of ceram-ics are perfect examples where understanding the structure-propertyrelationships at multiple scale levels was a key necessity for success.And amongst the crystallographic symmetries which have yielded themost varied properties, the perovskite system reigns supreme. I havededicated my research career to this system, exploring the influence ofcomposition and defect structure on both insulating and conductingsystems. I first will discuss the properties and characteristics of thisunique class of ceramics which allows them to be utilized both as elec-trical insulators as well as electrical conductors. I will then give someexamples in which the properties are tailored to meet requirements ofspecific applications: capacitors, solid oxide fuel cells, and sensors.

TMS Young Leaders Tutorial Luncheon and LectureRoom: 405

1:00 PMTMS Young Leader’s Lecture (Invited)W. A. Baeslack*, The Ohio State University, USA

Abstract Not Available

Edward DeMille Campbell Memorial LectureRoom: 407

12:45 PMCyclic Slip Irreversibilities and the Evolution of Fatigue Damage(Invited)H. Mughrabi*, University of Erlangen-Nürnberg, Germany

Repeated cyclic deformation of crystalline materials leads to fatiguedamage and, ultimately, to fatigue failure. While fatigue damage can

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 90

Tues

day

AM

www.matscitech.org 91

evolve in different forms, the origin of fatigue damage (excludingbrittle cracking) originates in most cases from some form of cyclicslip irreversibility, implying that usually a (very) small fraction of dis-location glide does not occur along the same path during reverseglide as during forward glide. This basic fact is responsible for thegradual development of surface roughness with a notch-peak geome-try which provides preferential sites for incipient crack formation.Cyclic slip irreversibilities generally arise from loss of dislocations atthe surface, cross slip of screw dislocations and from dislocation an-nihilation events and in particular cases, such as, for example, inbody-centred cubic metals, from the so-called slip plane asymmetry(operation of different slip planes in tension and compression). Con-sideration of the dominant microstructural processes leads to a self-consistent semi-quantitative model of localized cyclic deformation inpersistent slip bands with evolution of extrusions and stage I shearcracks. The fraction of irreversible slip decreases with decreasingloading amplitude (and increasing fatigue life). Studies of the evolu-tion of fatigue damage in High-Cycle Fatigue (HCF) tests at low am-plitudes which extend to >106 cycles to failure (or more, when per-formed in vacuum) are particularly conclusive with respect tounderstanding very slow damage evolution in the HCF regime or ateven lower amplitudes in the so-called UltraHigh Cycle Fatigue(UHCF) regime with fatigue lives in excess of 109 cycles. In the lec-ture, a historical review of experimental studies of fatigue damageevolution evolving from cyclic slip irreversibilities will be given, andappropriate semi-quantitative models will be discussed.

Edward Orton Jr. Memorial LectureRoom: 406

1:00 PMSol-Gel Processing: A Retrospective and Perspective (Invited)C. Brinker*, Sandia National Laboratories, USA

Since 1990 when George Scherer and I published the text, Sol-Gel Sci-ence, the field of sol-gel processing has advanced in several importantdirections. First a diverse range of new organically modified precur-sors has been employed, establishing the burgeoning field of hybrid(organic-inorganic) materials. Inclusion of organic ligands within in-organic frameworks has enabled the development of new functionsand applications in a diverse range of fields including catalysis, sens-ing, photonics, and electronics. Second, using hydrolyzed sol-gel pre-cursors as hydrophilic components during surfactant-directed mo-lecular self-assembly has ‘tamed’ the sol-gel process by imposingperiodic structural order on nanometer length scales. Initial ‘surfac-tant templated mesoporous’ materials, developed by Mobil Corpora-tion (designated MCM-41), were amorphous silicas composed of or-dered 2D hexagonal arrays of nanometer-sized cylindrical poreshaving analogies to zeolites. Since 1992, surfactant templating hasbeen extended to different oxide and hybrid materials systems andhas been developed for continuous thin films and spherical nanopar-ticles with applications such as membranes and low k dielectrics. Fi-nally separation of the hydrolysis and condensation steps of sol-gelprocessing via sequential adsorption reactions in a process calledatomic layer deposition (ALD) has allowed the formation of confor-mal thin films on arbitrary substrates with precision rivaling that ofmolecular beam epitaxy. This lecture will provide examples of someof these advances developed within my laboratory and forecast newdirections of sol-gel processing I expect to be realized in the nextdecade.

Electronic & Magnetic Materials:Electroceramics Technologies: The Past andFuture - A Celebration of the 50thAnniversary of the ACerS ElectronicsDivision

Electroceramic Technologies: Processing AdvancesRoom: 315Session Chair: Geoff Brennecka, Sandia National Laboratories

8:00 AMSol-gel Processing of Electroceramics (Invited)D. A. Payne*, University of Illinois at Urbana-Champaign, USA

Progress made in the sol-gel processing of electroceramics, frompowders to ceramic microstructures, is reviewed for the past 50 years.The advantages of powder-free methods, that continue to evolve, es-pecially by polymeric sol-gel processing, are described for perovskite-based materials. Examples are given for the densification of insulatingstructures at temperatures compatible with integration on Si. A vari-ety of metallo organic precursors are discussed, and the routes bywhich they transform to metal oxides are outlined. Case histories aregiven for the reduced- temperature processing of integrated capaci-tors, piezoelectric elements, and ferroelectric memory cells. The ex-tent by which sub-micron layers and nano-crystalline componentsbehave differently from bulk materials are considered, including, in-terface and residual stress effects.

8:40 AMNanoengineering the Defect Structure in Y1Ba2Cu3OySuperconducting Films for Tunable, High-Current Wires (Invited)T. G. Holesinger*, B. Maiorov, D. M. Feldmann, L. Civale, Los AlamosNational Laboratory, USA; D. Miller, V. Maroni, Argonne NationalLaboratory, USA; D. Larbalestier, Florida State University, USA; X. Li, M. W.Rupich, American Superconductor, USA

High critical current densities in YBa2Cu3Oy coated conductor wiresdepend upon the defects types and densities within the films. Recentwork has focused developing methodologies for introducingnanometer-sized defect structures for pinning of vortices. However,wire performance also depends upon the connectivity, alignment,and phase purity within the film. In short, coated conductor wiresmust contain engineered inhomogeneities on the nano-scale, whilebeing homogeneous on the macro-scale. Recent advances in high-performance YBCO coated-conductors are presented regarding filmdeposition, nano-engineering of defect structures and the overallcharacterization of the structural, chemical, magnetic, and supercon-ducting properties. Distinctions are made between processes thatoccur during film conversion from the precursors and those thatoccur via post processing of films. Prospects for further developmentof much higher Ic wires will be discussed.

9:20 AMGas Permeability in Nanoporous SubstratesS. J. Lombardo*, S. Patel, University of Missouri, USA

To reduce component size, nanosized powders are being used morefrequently in the fabrication of multilayer ceramic capacitors. As aconsequence of the small particle size, the gas permeability can begreatly reduced, which makes binder removal by thermal methods amore difficult process. In this paper, we show how the permeabilitycan be determined in the nanopore size range from the combinedoutcome of both experiments and modeling. This approach utilizesmeasurements of the flux through a substrate to determine the poresize, which is then used to determine the relative contributions fromKnudsen, slip, and laminar flow. This technique is first applied to

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 91

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania92

membrane materials with specified pore size and then to green ce-ramic tapes fabricated from nanosized perovskite powders powder.

Electroceramic Technologies: Advances inFerroelectricsRoom: 315Session Chair: Robert Schwartz, Missouri University of Science andTechnology

10:00 AMA Brief History of Ferroelectric Phenomenologies (Invited)L. Cross*, Penn State University, USA

Not surprising in view of its hideous structural complexity (112atoms/unit cell) perhaps the first successful phenomenological ap-proach was for Ferroelectric Rochelle Salt by H. Mueller which will beintroduced. For ceramist however a key breakthrough was the phe-nomenology for Barium Titanate (BaTiO3) by AF Devonshire a bril-liant mathematician and a world class bird watcher. His elegant for-mulation permitted the close description of all elasto-dielectricproperties in cubic, tetragonal, orthorhombic and rhombohedral sin-gle domain phases, and the correct description of double hysteresis attemperature just above the Curie Point. Extensions of the theory toantiferroelectrics to (NaxK1-x)NbO3, PZT and lower symmetryphases will be discussed with some words of caution.

10:40 AMFerroelectric Solid Solutions: Morphotropism, Microstructureand Electromechanical Properties (Invited)G. A. Rossetti*, University of Connecticut, USA; A. G. Khachaturyan, Rutgers,The State University of New Jersey, USA

Pseudo-binary ferroelectric solid solutions having morphotropicboundaries (MBs) are the most widely used materials for piezoelec-tric actuators and sensors. Following more than five decades of re-search alternative definitions of morphotropism have been applied tosuch systems and the physical origins of the large electromechanicalresponse they display remain controversial. It is shown that a self-consistent application of the Landau theory of phase transitions, theclassical theory of domains, and the Gibbs thermodynamics of solu-tions to the MB diagram reconciles disparate physical phenomenaconnected with the order of the diffusionless transitions between ad-jacent ferroelectric and paraelectric phases, the emergence of regionsof phase coexistence, and the competing thermodynamics of low-symmetry ferroelectric phases. The theory predicts a miniaturizationof the domain size near the MB resulting in large extrinsic contribu-tions to the electromechanical properties.

11:20 AMTime-resolved diffraction measurements in ferroelectrics(Invited)J. L. Jones*, A. Pramanick, University of Florida, USA; J. E. Daniels, EuropeanSynchrotron Radiation Facility (ESRF), France

Diffraction provides an effective means to characterize ferroelectricmaterials under unique loading conditions. Because non-180° do-main switching involves a change in the volume fraction of ferroelas-tic domain variants, these structural changes are measured in diffrac-tion by a change in the diffracted intensities of certain reflections(e.g., {002} in tetragonal PZT). Similarly, the converse piezoelectriceffect yields a change in lattice spacing that is also measured in dif-fraction. Using static electric fields, both lattice strains and domainswitching have been observed in bulk, polycrystalline piezoelectricceramics. Our recent efforts have utilized time-resolved and strobo-scopic diffraction techniques to observe similar microstructural ef-fects under dynamic electric fields. This talk will include measure-ments conducted with neutron, synchrotron X-ray, and laboratoryX-ray sources.

Electronic & Magnetic Materials: PerovskiteOxides: Films, Nanostructures, Properties,and Applications

Oxide Films and NanostructuresRoom: 316Session Chairs: Qi Li, Pennsylvania State University; Hans Christen,Oak Ridge National Laboratory

8:00 AMChemical Solution Deposition Method for Epitaxial, Thin Films(Invited)F. F. Lange*, UCSB, USA

The chemical solution deposition (CSD) method initiates with solu-tions formulated with metal-organic molecules that, after applicationvia spin-coating, dip coating, stamping, etc, to a single crystal sub-strate, decomposition (pyrolysis) via heating, crystallizes, and pro-duces a single crystal thin film via several different processes. Precur-sor molecules can be used to synthesize multi-element oxides,carbides, nitrides, etc. Metastable phases are common due to the lowtemperature crystallization of the glassy film formed after pyrolysis.The polycrystalline film converts to a single crystal film via graingrowth from the substrate. When the structural mismatch is large,epitaxial islands will form, which can be used as a ‘seed’ layer for fur-ther deposition and growth of a continuous epitaxial film. The CSDmethod is generally limited to produce thin (< 1 μm) films, viz.,thicker films can exhibit mud cracking due to the constrained shrink-age of the precursor film during spin-coating.

8:40 AMA Review of Thermodynamic and Kinetics Factors in Solution-Derived Thin Film Crystallization (Invited)R. W. Schwartz*, Missouri University of Science and Technology, USA

Chemical solution deposited (CSD) thin films are utilized for manyelectronic applications. Control of thin film microstructure requiresan understanding of the thermodynamic and kinetic factors associ-ated with the phase transformation into the crystalline state. Theseinclude: surface energetics; free energy differences between the crys-talline and amorphous states; and the kinetics of grain growth. Otherexperimental factors, such as heat treatment ramp rate and hold timealso influence thin film microstructure. The thermodynamic and ki-netic aspects of thin film crystallization are reviewed and strategies toinfluence microstructure are discussed. The ability to “control” mi-crostructure (e.g., grain size and orientation) is reviewed in the con-text of precursor solution chemistry effects and heat treatmentmethod. Opportunities to improve current understanding throughstudy of model systems are also considered.

9:20 AMStoichiometry issues in pulsed laser deposition (Invited)T. Ohnishi*, The University of Tokyo, Japan

Epitaxial oxide thin films are at the heart of new oxide electronicapplications. Complex oxide films are often grown by pulsed laserdeposition (PLD) because the technique is believed to be material-agnostic. Here we show that one of the fundamental premises tojustify the use of PLD, that material is transferred from a target tothe film without stoichiometry deviations, is incorrect even whenno volatile elements are involved. The commonly-used solution ofincreasing the laser energy density above a material-specific thresh-old value to obtain stoichiometric films doesn’t work. Lattice pa-rameter deviations in oxide films, which are often incorrectly as-cribed to oxygen loss, correlate with cation nonstoichiometry incase of SrTiO3. We show that proper choice of ablation laser condi-tions is essential and often more important than the growth temper-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 92

Tues

day

AM

www.matscitech.org 93

ature and oxygen pressure for obtaining bulk-like properties inoxide heterostructures.

10:00 AMCombinatorial Study of the HfO2-TiO2-Y2O3 System usingPulsed Laser Deposition Library FilmsP. K. Schenck*, J. L. Ruglovsky, P. G. Burke, N. D. Bassim, M. L. Green,NIST, USA

We demonstrate that combinatorial methodology may be used as atool for the metrology of crystallinity boundaries in ternary thinfilms. The HfO2-TiO2-Y2O3 ternary thin film system was realizedvia combinatorial Pulsed Laser Deposition (PLD) at several substratetemperatures from 300°C to 700°C. In the higher temperature libraryfilms (≥400°C) a visible boundary line was observed across the sam-ple due to an abrupt change in the effective refractive index. Inspec-tion via mapping x-ray diffraction confirms that the line separatescrystallized from amorphous regions of the film. With librariesgrown at increasing temperatures, we observed that the boundarymoves, as more of the film becomes crystalline. We also observechanges in the crystallinity boundary with changes in composition,including binary films. Our experiments on a technologically relevanthigh-k system offer insight into the thermal stability necessary for ad-vanced device applications.

10:20 AMMagnetoelectric epitaxial thin layer two phase composites(Invited)D. Viehland, J. Li, L. Yan*, Virginia Tech, USA

ME composites have been shown to have large ME voltage coeffi-cients. Of particular interests are self-assembling two-phasenanocomposites. In this talk, we will show how epitaxial constraintcan be used to design two phase morphologies in CFO-BiFeO3 (orCFO-BFO) epitaxial films, and how the phase stability and proper-ties of the two individual phases can be altered by said constraint.We have engineered various nano-structures ranging from nano-rods to nano-belts by (i) orientation of substrate, (ii) epitaxialstrain, and (iii) diffusion. Investigations of the mechanism of nano-structure formation over a range of temperatures revealed growthmechanism of nano-structure. Our primary goal is to determine thefundamental relationship between (i) multiferroic properties, (ii)ME coupling, (iii) crystal morphologies, and (iv) crystal structure.By epitaxial engineering, we are trying to control or optimize thestructure and multiferroic properties of two phase nano-compositeME thin films.

11:00 AMMagnetic, Ferroelectric, and Sensor Materials Prepared byExtraction-Pyrolysis TechniqueT. N. Patrusheva*, A. I. Kholkin, Siberian Federal University, RussianFederation

High standards of special electric, magnetic, optical, mechanicalproperties can be achieved by the usage of high purity starting ma-terials and synthetic procedures ensuring proper chemical, grainsize and phase uniformity in the final product. For the homoge-neous and pure functional composite oxide preparation we pro-posed the extractive-pyrolysis technique. The nanosize FeCoO, SnO,InSnO, PbZrTiO thin films and powders were obtained. NanosizeCo-ferrite and CoZn-ferrite films prepared by extraction-pyrolysistechnique were suited for magneto-optical recording media and finemicrostructure prevent from media optical noise. The geterostruc-tures of ferrites with molecular sieve MSM-41 showed magneticparticles with high value of coercitive force about 5000 Oe. Proper-ties of LaSrMnO films prepared by extraction-pyrolysis techniquedepending on the annealing conditions are changed from spine glassto ferromagnetic.

Electronic & Magnetic Materials:Ferroelectrics and Multiferroics

Epitaxial and Oriented Films, Materials Integration,Strain-induced PhenomenaRoom: 318Session Chair: John Prater, Army Research Laboratory

8:00 AMDomain Stability for Ferroelectric Thin Films under AnisotropicIn-plane Substrate Strains: A Phase-field SimulationG. Sheng*, J. Zhang, Y. Li, S. Choudhury, Z. Liu, The Pennsylvania StateUniversity, USA; Q. Jia, Los Alamos National Laboratory, USA; L. Chen, ThePennsylvania State University, USA

The misfit strains between a ferroelectric film and its substrate couldplay an important role in changing the domain stability of ferroelec-tric thin films. Recent experiments have shown that the dielectricproperties of thin films may be affected significantly by anisotropicstrains. The objective of this research is to employ the phase-field ap-proach to study domain stabilities for ferroelectric PbTiO3 andBaTiO3 thin films under different temperatures. Based on the simula-tion results, the “misfit strain-misfit-strain” domain/phase stabilitydiagrams with full range of experimentally accessible compressiveand tensile strains were constructed. The diagram displays variouscombinations of tetragonal, orthorhombic and rhombohedra phasesunder different temperatures and strains. The domain stability andstructure are also compared with thermodynamic calculations undersingle-domain assumptions.

8:20 AMDomain stability and morphology of BaTiO3 thin films underanisotropic strainsG. Sheng*, J. Zhang, Y. Li, S. Choudhury, Z. Liu, The Pennsylvania StateUniversity, USA; Q. Jia, Los Alamos National Laboratory, USA; L. Chen, ThePennsylvania State University, USA

The effect of anisotropic strains on the phase transitions and do-mains structures of BaTiO3 thin films was studied using both ther-modynamic calculations and phase-field simulations. We employed arecently developed eighth-order polynomial to describe the free en-ergy dependence on polarization which allows us to explore the fullrange of anisotropic strains that are accessible to experiments. Thedomain stability diagrams, graphical representation of stable ferro-electric phases and domain structures as a function of strains, at sev-eral representative temperatures were generated, and the correspon-ding domain structures were analyzed. It is expected that suchdiagrams will provide guidance for interpreting experimental meas-urements and observations as well as to the design of BaTiO3 filmswith specified domain structures.

8:40 AMSurface and thickness effect on ferroelectric transitiontemperature in ultrathin BaTiO3 filmsY. Li*, L. Chen, D. G. Schlom, S. Trolier-McKinstry, X. Xi, Penn StateUniversity, USA; J. Shen, Purdue University, USA; Q. Jia, Los Alamos NationalLaboratory, USA; P. Turner, D. A. Tenne, Boise State University, USA; M.Biegalski, Oak Ridge National Laboratory, USA; D. Fong, Argonne NationalLaboratory, USA

The effect of thickness on the phase transition temperatures inBaTiO3 films was studied using phase-field method. The contribu-tions of depolarization field, substrate constraint, and interfacial ef-fects are considered. The results are compared to experimental meas-urements of transition temperatures using Ultraviolet Ramanspectroscopy and x-ray diffraction on a series of MBE-grown BaTiO3films with layer thicknesses ranging from 4 to 25 unit cells on SrTiO3(001)-oriented substrates. We will discuss the mechanisms leading to

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 93

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania94

a very broad range of transition temperatures as a function of layerthickness, being as high as about 900 K for the 10-nm-thick (25 unitcells) BaTiO3 film.

9:00 AMDomain Structure and its Effec on the Properties of EpitaxialBiFeO3 Thin Films Grown on Exact and Miscut (001) SrTiO3Substrates (Invited)X. Pan*, Y. Chen, University of Michigan, USA; R. R. Das, D. M. Kim, S. H.Baek, C. Eom, University of Wisconsin-Madison, USA

In this paper, epitaxial BiFeO3 thin films with a SrRuO3 bottom elec-trode were fabricated by sputtering on both exact and miscut (001)SrTiO3 substrates. Domain structures of epitaxial BiFeO3 thin filmswere studied by transmission electron microscopy. BiFeO3 on exact(001) SrTiO3 substrates are composed of both 109° and 71° domainwalls; in contrast, only stripe domains with 71° domain walls are ob-served in BiFeO3 on 4° miscut (001) SrTiO3 substrates. The domainwidth in BiFeO3 on 4° miscut substrates increases as film thicknessincreases due to a reduction in domain wall energy. The domain con-figurations of BiFeO3 films affect their ferroelectric switching behav-ior due to the pinning at the junctions between 109° and 71° domainwalls. From this study, the two different domain configurations ob-served in BiFeO3 films are caused by both the substrate anisotropyand the step-flow growth of BiFeO3 on the miscut SrTiO3 substrates.

10:00 AMPhase-field model of the relationship of domain size with grainsize in thin filmsB. Winchester*, S. Choudhury, L. Chen, Pennsylvania State University, USA

A phase-field model was developed for studying the effect of poly-crystallinity on the domain size and hysteresis loop of epitaxial ferro-electric thin films. A sixth-order Laundau-Devonshire thermody-namic potential was employed to describe the energy of apolycrystalline PbZr0.2Ti0.8O3 thin film at room temperature. Therelative sizes of ferroelectric domains on PbZr0.2Ti0.8O3 thin filmsunder different substrate strains and substrate orientations were ob-tained and compared. The average domain size was found to be af-fected by the grain size.

10:20 AMMicrostructures and dielectric properties of (Pb,Sr)TiO3 thinfilms with large dielectric tunability (Invited)Y. Lin*, University of Electronic Science and Technology of China, China

(Pb,Sr)TiO3 (PSTO) thin films were epitaxially grown on various sin-gle crystal substrates. Microstructures of the films were investigatedusing high resolution x-ray diffraction and electron microscopy whilethe dielectric properties were characterized. Crystal distortion and in-terface relationships were compared. PSTO films on LaAlO3 andMgO exhibit a tetragonal distortion whereas the film on NdGaO3substrate shows an orthorhombic distortion. The orientation of thefilm is related to the fabrication condition such as cooling rate. Strainrelaxation during the growth of the films was discussed. Dielectricproperties of the films show a strong correlation with the microstruc-tures. Measurements at 1.0 MHz reveal that the films have very highroom temperature dielectric constants over 3000, extra large dielec-tric tunability ~ 50%, and low dielectric loss, suggesting the epitaxialPSTO thin film is a good candidate for room temperature tunablemicrowave device applications.

11:00 AMComparison of the Material Properties of Ba0.60Sr0.40TiO3 (BST)Thin Films Fabricated via UV-Assist and Conventional ThermalProcess Science Protocols (Invited)M. W. Cole*, U.S. Army Research Laboratory, USA; A. Podpirka, S.Ramanathan, Harvard University, USA

The effect of ultra-violet (UV)-assisted annealing on the structural,dielectric, and insulating properties of Ba0.60Sr0.40TiO3 (BST) thin

films was investigated. The material properties of sputtered BST filmsannealed via conventional thermal annealing and UV-assisted ther-mal annealing process protocols were compared and evaluated. X-raydiffraction results showed contracted lattice constants and enhancedcrystallinity for the BST films annealed via UV-assist. Isothermal-temporal annealing experiments, over a broad range of annealingtimes, revealed that the UV-assist annealed films possessed enhancedcrystallization, and lattice parameters closer to bulk values with re-spect to the conventional thermal annealed films. The leakage currentdensity and dielectric loss of the films, was significantly reduced byemploying UV-assisted annealing.

11:40 AMPiezoelectric Microgenerator: Challenges and ApplicationsH. Kim*, C. Park, W. Lee, B. Gnade, S. Priya, University of Texas, Arlington, USA

Piezoelectric energy harvesters are projected to be suitable energysources for sensors and associated electronics used in industrialhealth monitoring, and aircraft structural health monitoring. Thismanuscript outlines the progress in developing the energy harvestingprototypes. It compares the progress made in the realization of piezo-electric microgenerators with that of electromagnetic and electro-static generators and identifies the parameters that need to be re-ported in subsequent publications for rationale comparison. Further,it reports our results on the fabrication and characterization of thepiezoelectric cantilever based energy harvester. We used two ap-proaches to fabricate the microgenerator: (i) laser micromachining,and (ii) MEMS process. Results will be presented to compare the re-sults from both these approaches.

Electronic & Magnetic Materials:International Symposium on AdvancedDielectric Materials & Electronic Devices

Composition, Processing, Microstructure, andProperty Relationships IIIRoom: 317Session Chair: Sharmila Mukhopadhyay, Wright State University

8:00 AMScanning Electron Acoustic Microscopy Studies of FerroicDomains (Invited)R. Guo*, Y. Lee, J. H. Wang, University of Texas at San Antonio, USA; A. S.Bhalla, Pennsylvania State University, USA

Scanning Electron Acoustic Microscopy (SEAM) is used successfully inthe study of ferroelectric and ferroelastic domain features of variouscrystals and polycrystallines such as LiNbO3, BaTiO3, LaAlO3, andGd2(MoO4)3. The 180 degree domain features and their longitudinaldepth profile are revealed using the SEAM without invasive surfacepreparation. Piezoelectric radial and thickness resonance modes of thetransducer permit sensitive detection of anisotropic thermal wave image.It is found that effective electromechanical coupling (below resonance)can be used for continuous detection; however, due account needs to begiven to anisotropy-induced image distortion. Thermo-acoustic cou-pling mechanism is applied to give qualitative interpretation to the evo-lution of the domain structures upon modulating conditions. The re-sults are also discussed in terms of the piezoelectric mode selection andthe resulted sensitivities of the transducer used in this technique.

8:40 AMFunctionalization of Na0.5Bi0.5TiO3 for applications in electronicdevices (Invited)D. Suvorov*, M. Spreitzer, J. König, M. Znidarsic, S. D. Skapin, B. Jancar, JozefStefan Institute, Slovenia

Na0.5Bi0.5TiO3(NBT)is a complex perovskite with two different ionsat the A-site of the structure. The compositional disorder of NBT re-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 94

Tues

day

AM

www.matscitech.org 95

veals its relaxor nature. Relaxor materials are applicable in many elec-tronic devices; however, most of them are based on lead, which is haz-ardous to health and the environment. Since NBT does not containlead it has attracted a lot of attention, and has been proved to be analternative candidate. In this study the NBT composition was modi-fied by various non-polar compounds, such as Li3xLa(2/3)-xTiO3and NaTaO3. The obtained samples exhibited improved voltage-tun-able characteristics, especially for higher additive concentrations. Wedetermined that this improvement relates to low-temperature dielec-tric relaxations. The composition of NBT was also improved by polarcompounds, such as K0.5Bi0.5TiO3. In this case the samples exhib-ited enhanced piezoelectricity, which was related to their mor-photropic phase boundaries and ferroelectric polar order.

9:00 AMFabrication of piezoelectric ceramics with oriented structureusing a strong magnetic fieldS. Tanaka*, K. Uematsu, Nagaoka University of Technology, Japan

Increasing concern for the environment makes the lead-free, bismuthtitanate family very promising as next generation ferroelectric mate-rials. The target of this study is to fabrication of strontium bismuthtitanate ceramics with oriented grain and high density, and to evalu-ate the influence of particle size on the orientation structure duringthe shaping using a high magnetic field (10 Tesla) and during subse-quent sintering. The orientation degree of strontium bismuth ti-tanate ceramics after sintering is high above 0.6 when the particlessize increased from 0.5 to 1.0μm. The remarkable development oforientation structure during sintering was observed by comparingXRD patterns between green and sintered body. When using largeparticle size (0.5-1.0μm), the orientation degree increased from 0.2 to0.6 with densification and grain growth.

9:20 AMInfluence of the processing methods in the formation of theperovskite phase in PZN-10PT ceramic systemC. F. Villaquiran Raigoza, D. Garcia*, J. A. Eiras, R. H. Kiminami,Universidade Federal de Sao Carlos, Brazil

The objective of this work is to analyze the influence of the synthesismethods: mixed oxides and mechanical activation and their parame-ters in the formation of the perovskite phase in PZN-10PT ceramicsystem. The same analysis was followed in the densification methods:hot uniaxial pressing, conventional and reactive sintering and theirparameters. Was found that for the mixed oxides it is possible to reach~74% of perovskite phase when nitrogen atmosphere is used at1000oC for times over 2h. For all densification methods it was possi-ble to reach 100% of the perovskite phase up to ~50μm in depth ofthe surface (in the inner pyrochlore, perovskite and zinc-rich oxidephases are present). This result depends of specific conditions of pro-cessing for each method. This investigation shows that it is possible toobtain perovskite single phase PZN-PT ceramics (at least in thick filmform) using controlled processing conditions even from mixed oxidepowders as raw material.

10:00 AMFerroelectric Domains in Lead Free Piezoelectric Ceramics(Invited)T. Ogawa*, Shizuoka Institute of Science and Technology, Japan; M.Furukawa, TDK Corporation, Japan

DC poling field dependence of piezoelectricity was investigated forthe domain structures in lead free ceramics composed of (1-x)(Na,K,Li,Ba)(Nb0.9Ta0.1)O3-xSrZrO3 (x=0-0.07) comparing withthe structures of PZT, PbTiO3 (PT) and BaTiO3 (BT) ceramics. Pol-ing was conducted at 150°C for 30 min while varying the poling field(E) between ±5.0 kV/mm. Increasing x from 0 to 0.05, the relative di-electric constant (εr), kp, frequency constant of kp (fcp) and d33 vs. Eshow typical domain clamping at a specific E. The change in the εr,kp, fcp and d33 vs. E became small at x=0.06-0.07, because of the ap-

proaching to the paraelectric phase. The ceramics at x=0 show typicalεr, kp, fcp and d33 vs. E such as BT and PT ceramics. The maximumkp (47%) and d33 (310 pC/N) were obtained at x=0.05 with lowestfcp of 2980 Hz-m appearing typical εr, kp, fcp and d33 vs. E such astetragonal PZT hard ceramics. It was clarified that large kp and d33 inthe lead free ceramics needed to realize low fcp which corresponds tolow Young’s modulus.

10:20 AMNeodymium solubility in the PLZT CeramicsE. R. Botero, D. Garcia*, J. A. Eiras, Federal University of Sao Carlos, Brazil

Transparent ceramic materials as lanthanum modified lead zirconatetitanate (PLZT) constitute a class of materials that has received atten-tion for more than 30 years, due to their excellent electro-opticalcharacteristics and improved optical quality. Nevertheless, in the last10 years this material has received an especial interest as host for lu-minescent ions with emission on the near infrared range, as example,the Nd+3, raising its application to the laser construction besides thisferroelectric properties. In this work, PLZT(Pb0.91La0.09)(Zr0.65Ti0.35)0.9775O3 ceramics doped with differ-ent amounts of neodymium oxide (Nd2O3) were processed andcharacterized. The powders were prepared by the solid state reactionmethod, thus, cold pressed and conventionally sintered. XRD struc-tural analysis and impedance spectroscopy were performed to inves-tigate the solubility limit of the rare earth ion in the PLZT lattice. Aformation of a secondary phase was observed for doping concentra-tions higher than 1.0 weight % (~2.0 mol %).

10:40 AMTexturing of PMN-PT Ceramics via Templated Grain Growth(TGG): Issues and PerspectivesM. E. Ebrahimi*, SorenTec, Canada

The issues in texturing of PMN-PT by Templated Grain Growth(TGG) are discussed. TGG is a technique to make grain oriented ce-ramics with high anisotropy properties in lower cost. In recent years,extensive researches are focused on obtaining higher microstructuralorientation and high d33 (1100-1600 pC/N) in low field and highstrain (>0.3% at 50 kV/cm) were reported. Nevertheless, the tech-nique still faces various problems in achieving high and reliablepiezoelectric properties. High aspect ratio strontium titanate (ST)and barium titanate (BT) were synthesized and incorporated inPMN-35PT matrix. High Lotgering factors (~70-90%) were ob-tained. Fluctuations in piezoelectric properties of sintered samplesare discussed in terms of microstructural aspects and properties andinteractions of seeds and matrix. Finally, the principles and develop-ments in viable high isometric perovskite seeds and the perspective ofthe TGG technique for texturing of PMN-PT are presented.

11:00 AMHigh Temperature Piezoelectric Properties of Some BismuthLayer-Structured Ferroelectric Ceramics (Invited)T. Takenaka*, T. Tokutsu, H. Miyabayashi, Y. Hiruma, H. Nagata, TokyoUniversity of Science, Japan

The maximum operation temperature of piezoelectric materials forsensors is limited by the Curie temperature, Tc, with the level of sen-sitivity by the piezoelectric voltage constant, g. Bismuth layer-struc-tured ferroelectrics (BLSFs) are very attractive from the viewpoint ofhigh temperature sensor applications, because BLSFs are character-ized by their low dielectric constant, εs, and high Tc. In this study, wefocused on their piezoelectric properties over the wide temperaturerange (~500 °C) of some BLSF ceramics with high Tc such asCaBi2Ta2O9 (CBT2), Bi4Ti3O12 (BIT), Na0.5Bi4.5Ti4O15 (NBT)and CaBi4Ti4O15 (CBT4). For example, the Tc of V-modified BIT,Bi4Ti0.98V0.02O12 (BITV-0.02) ceramic was 678 °C. The grain ori-ented BITV-0.02 indicated large g33 ~27X10-3 Vm/N from the in-situ measurements of the resonance and antiresonance method at 400

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 95

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania96

°C. Some BLSF ceramics including BITV-0.02 seem to be good candi-dates for lead-free high-temperature piezoelectric sensor materials.

11:20 AMNanosized Barrier Layer Capacitor Phenomenon for the Origin ofthe Huge Dielectric Constant and Semiconducting CoexistentFeatures in Perovskite-type Structures (Invited)P.R. Bueno*, R. Tararan, J. Varela, Sao Paulo State University, Brazil

This work proposes a polaronic stacking fault defect model as the originof the huge dielectric properties of same perovskite-type structures. Themodel was successfully tested in CaCu3Ti4O12 (CCTO) materials. Themodel reconciles the opposing views of researchers on both sides of theintrinsic versus extrinsic debate about the origin of the unusually highvalues of dielectric constant measured for CCTO in its various forms.Therefore,by considering stacking fault as the origin of the high dielectricconstant phenomena it was showed that IBLC mechanism is enhanced byanother similar, but differently in nature, mechanism that operates in ananoscale range due to polarons defects associated with stacking fault, amechanism that was referred as Nanosized Barrier Layer Capacitance(NBLC). The NBLC approach explains the origin of the CCTO’s huge di-electric constant coexisting with semiconducting features.

11:40 AMAll-ceramic Percolative Composites with a Colossal DielectricResponseV. Bobnar*, M. Hrovat, J. Holc, M. Kosec, Jozef Stefan Institute, Slovenia

All-ceramic percolative composites based on perovskite ferroelectric andruthenium-based conductive ceramics were developed. The structuralanalysis revealed that there were no chemical reactions between the con-stituents during processing, which resulted in a perfect percolative struc-ture – conductive ceramic grains dispersed in a dielectric ceramic matrix.Thus, in the lead-based PZT–Pb2Ru2O6.5 and PMN-PT–Pb2Ru2O6.5 andin the lead-free KNN–RuO2 systems the dielectric response follows thepredictions of the percolation theory – the dielectric constant actually di-verges on approaching the percolation threshold (values as high as 50,000were detected at 1 kHz at room temperature) and the determined criticalexponents and percolation points agree reasonably with the theoreticallypredicted values. Finally, not only structural and dielectric results but alsoelectromechanical properties demonstrate the potential of these compos-ites for use as high-dielectric-constant materials in various applications.

Electronic & Magnetic Materials: Pb-Free, Pb-Bearing Joining and Packaging Materials andProcesses for Microelectronics

Microstructural CharacterizationRoom: 319Session Chairs: C. Robert Kao, National Taiwan University; IverAnderson, Ames Laboratory

8:00 AMMinimal Alloy Additions for Both Nucleation Control andThermal Aging Resistance of Near-Eutectic Sn-Ag-Cu Solder Joints(Invited)I. E. Anderson*, Ames Laboratory, USA; J. Walleser, Iowa State University,USA; J. Harringa, A. Kracher, F. Laabs, Ames Laboratory, USA

Some 4th element modifications (X=Zn, Mn, Co, Ni, and Fe) ofnear-eutectic SAC solders (SAC+X) were found to suppress growthof intermetallic (Cu3Sn) at the Cu substrate interface and to pro-mote retention of ductility for shear mode failure in early work onthermal aging (150C, up to 1000h) at significant addition levels, e.g.,0.3wt.%, in SAC3709 solder joints. Some X additives, especially Mnand Fe, also were found (in on-going work) to catalyze desirable sol-der joint microstructures (avoiding Ag3Sn pro-eutectic blades) inCu/Cu joints at low concentrations (0.10-0.15wt.%) in SAC3595,even at low cooling rates (0.17C/s) that mimic BGA reflow. The cur-

rent work will conclude the SAC3595+X catalysis study, finding min-imum effective X values for the most beneficial catalysts (Mn, Fe,others?), and will examine SAC3595+X(min) solder joints for ther-mal aging effects at 150C. Supported through Ames Lab contract no.DE-AC02-07CH11358.

8:40 AMTEM Characterization of Directionally Solidified Ag-Cu-Sn AlloysB. Hamilton*, H. McGee, D. Lewis, Rensselaer Polytechnic Institute, USA

Ag-Cu-Sn has recently been identified as the industry standard lead-free solder alloy. This alloy consists of a non-faceted (Sn) matrix andtwo faceted intermetallic phases: Ag3Sn and Cu6Sn5. In order to bet-ter understand the solidification behavior of this alloy, directionallysolidified ingots were prepared and characterized in a previous pres-entation. We continue this characterization through measurement ofthe orientation relationship of the intermetallic phases within the di-rectionally solidified, near-eutectic Ag-Cu-Sn. Sample preparationwas done using the focused ion beam (FIB) technique to obtain a 50nm thick sample and transmission electron microscopy (TEM) wasused to characterize the orientation relationship between phases. Pre-liminary results on these materials and structures will be presented.Ultimately, this data can be used to better understand the kinetics ofphase growth and to help control solidification microstructures.

9:00 AMEffect of Al addition on microstructure and wettability on Sn-ZnLead-free SoldersX. Wang*, C. Li, J. Ma, Y. Zhang, University of Science and TechnologyBeijing, China

Sn–Zn solders have been highly recommended as a substitute for eutec-tic Sn–Pb solder due to their low melting point, excellent mechanicalproperties and low cost. However, some important issues such as wetta-bility, easy oxidation, are still barriers for their practical use. In the pres-ent study, six Sn-Zn solder alloys were designed, they were 76Sn-(24-x)Zn-xAl, (x=0.8 to 11.3, at%). It was found that the melting points ofthese alloys were close to 200C with the melting range smaller than 3.5C.The wettability was studied by measuring wetting angles on Cu sub-strate. Several different fluxes were used. The results showed that the Sn-Zn-2.4Al solder alloy had the best wettability, the wetting angel reached12° on Cu substrate. The fluxes benefited the forming of IMC in the sol-der joints. The microstructure and interface IMC were investigated.

9:20 AMSpalling and Voiding in the Liquid State: Eutectic Sn-Ag-CuSolders on Au/Ni SubstratesM. Gao*, E. J. Cotts, Binghamton University, USA

Interfacial reactions between near-eutectic Sn-Ag-Cu lead-free solderalloys and Au/Ni substrates were studied at peak temperatures between200C and 300C. The intermetallic compound (Cu,Ni,Au)6Sn5 formedfirst at the interface between the solder alloy and the substrate, while(Ni,Cu)3Sn4 formed between the (Cu,Ni,Au)6Sn5 and the substratewhen the Cu supply in the solder diminished. At certain points in thereaction, voids were observed to form within the (Cu,Ni,Au)6Sn5compound. Under certain conditions, at temperatures above the solderliquidus, the (Cu,Ni,Au)6Sn5 intermatellic layer was observed to spalloff of the (Ni,Cu)3Sn4 compound. The dependence of these phenom-ena on thermal history, solder composition and volume, Au thicknessand metallization pad area was investigated. In particular, relations be-tween these parameters and the thickness of the intermetallic layers,the degree of void formation and the amount of spalling are reported.

10:00 AMKirkendall Void Formation in the Reaction Between Cu Substrateand Lead-free Solders (Invited)Y. W. Wang, C. Kao*, National Taiwan University, Taiwan

It has been reported that the reactions between Cu substrate andlead-free solders might lead to the formation of the Kirkendall voids,

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 96

Tues

day

AM

www.matscitech.org 97

which are detrimental to the joint strength. Nevertheless, the forma-tion of these voids is not consistent in these reactions reported in theliterature: some researchers saw them while others did not. Such in-consistency suggests that not all the key factors for the formation ofsuch voids have been identified. The objective of this study is to re-port that how this inconsistency comes about. In other words, we willreport the key factors responsible for the formation of the Kirkendallvoids. Our preliminary results that both the solders and the Cu sub-strates play critical role for the Kirkendall void formation.

10:40 AM2-D and 3-D Characterization of Sn Crystal Orientations andMicrostructural Evolution in Lead-free Solder JointsT. R. Bieler*, Michigan State University, USA; T. Lee, Cisco Systems Inc., USA;D. S. Robinson, Argonne National Laboratory, USA

Many Sn based lead free SAC solders solidify in single or multi-crys-tal orientations, commonly showing cyclic twinning. Statistical char-acterization of the fraction of balls that are single or multi-crystals ina 14x14 1mm pitch PBGA package was measured at several stages ofprocessing history, ball attach, board attach, and after combinationsof aging and thermal cycling. Approximately 30% of the balls in eachspecimen were characterized with OIM and polarized light mi-croscopy. Because a 2-D section does not reveal the full volumetricarrangement, 3-D measurements of crystal orientations were madeon selected solder balls from selected rows of solder joints extractedfrom a package, and the full volume was interrogated using 100 keVsynchrotron radiation. In-situ thermal cycling allowed thermally in-duced strains to be characterized, along with changes in volume frac-tion of multi-crystal orientations that resulted from thermal cycling.

11:00 AMInvestigation of Various Properties of Lead Free SoldersS. Knott*, M. Hindler, Z. Li, C. Schmetterer, P. Terzieff, A. Mikula, Universityof Vienna, Austria

Different properties of various lead free solders have been investi-gated. The wetting angles, viscosity, surface tension and thermody-namic properties of Ag-Cu-Sn, Ag-Bi-Sn, Ag-Au-Sn, Au-Cu-Sn andPd-Sn-Zn have been determined. The thermodynamic properties ofthe ternary Ag-Au-Sn, Au-Cu-Sn, and Pd-Sn-Zn systems have beendetermined with the EMF method with a liquid electrolyte as well aswith a Calvet type calorimeter. With the data obtained by the calori-metric method the viscosity of the Ag-Au-Sn system has been calcu-lated using the model of Iida et al. The sessile drop method was usedfor the determination of the surface tension of the Ag-Bi-Sn system.The results have been compared with the calculated surface tension,already published by Terzieff et al. Additional results of the wettingangle of the Ag-Cu-Sn alloy with various compositions on copperand nickel substrate, as well as the temperature dependency of thewetting angles and some intermetallic structures will be presented.

Environmental & Energy Issues: Ceramicsand Glass for Waste Minimization,Stabilization, and Disposition

Waste Glass Leach Testing and ModelingRoom: 326Session Chairs: James Marra, Savannah River National Lab; GeorgeWicks, Savannah River National Lab

8:00 AMSCK.CEN R&D on the interaction between nuclear waste glass andclay near-field materials (Invited)P. Van Iseghem*, K. Lemmens, E. Valcke, M. Aertsens, K. Ferrand, SCK.CEN,Belgium; M. Aertsens,

SCK.CEN has developed over a long years time a research pro-gramme to identify the dissolution processes of vitrified high-level

waste glass in the potential near-field environment of a geologicaldisposal site. We mainly focussed on clay as the near- (and far-) fieldmaterial. The R&D involved (1) the identification of some key basicprocesses, (2) the investigation of the coupled processes, (3) the mod-elling of the processes under (2), (4) the study of the release of the ra-dionuclides of interest, (5) the demonstration through field testing,and (6) the prediction of the lifetime of the vitrified waste and inter-action with the safety assessment of the disposal site. The presenta-tion will highlight the methodologies developed, and some of themain results.

8:20 AMGLAMOR - or how we achieved a common understanding on thedecrease of glass dissolution kinetics (Invited)P. Van Iseghem*, M. Aertsens, SCK.CEN, Belgium; S. Gin, D. Deneele, CEA,France; B. Grambow, SUBATECH, France; D. Strachan, P. McGrail, PNNL ,USA; G. Wicks, SRNL, USA

This presentation summarizes the GLAMOR project, a concerted ac-tion sponsored by the European Commission (2001-2004) that hadas objective to achieve a common understanding of the decrease ofdissolution rate of high-level radioactive waste glass with progress-ing duration. The literature was reviewed, experimental databasesand analytical models were selected. The project partners then allapplied the models to the selected data. The main conclusions were(1) both affinity and kinetic processes affect the dissolution rate de-crease, but the occurrence of a long-term residual dissolution rate ismuch more important, and (2) more efforts should be spent to qual-ify the main modelling parameters (Si saturation concentration, Sidiffusion coefficient, final dissolution rate) in order to reduce mod-elling uncertainties.

8:40 AMThe Product Consistency Test (PCT): How and Why It WasDeveloped (Invited)C. M. Jantzen*, N. E. Bibler, Savannah River National Laboratory, USA

The Product Consistency Test (PCT) is used world wide for testingglass, glass-ceramic, and ceramic waste forms for high level waste(HLW), low level waste (LLW), and hazardous wastes. Developmentof the PCT was initiated in 1986 because HLW glass waste forms re-quired extensive characterization before actual production began andrequired continued characterization during production (25+ years).The test underwent extensive development from 1986-1994 when thefirst revision became an ASTM standard. The PCT was shown to bevery reproducible, to yield reliable results rapidly, to distinguish be-tween glasses of different durability and homogeneity, and to easilybe performed in shielded cell facilities with radioactive samples. Test-ing included both inter- and intra-laboratory round robins with non-radioactive and radioactive samples. In 1997, the scope was broad-ened to include hazardous and mixed (radioactive and hazardous)waste glasses. In 2002, the scope was broadened to include glass-ce-ramic waste forms.

9:00 AMUsing Glass Dissolution Test Results in Performance Models(Invited)W. Ebert*, Argonne National Laboratory, USA

The degradation model used to calculate radionuclide releases fromborosilicate glass high-level waste forms in Performance Assessmentcalculations is based on a mechanistic model that was developed forthe dissolution of aluminosilicate minerals and modified for use withglasses. In this paper, the roles of laboratory tests in developing themechanistic model, simplifying the model for use in PA calculations,determining model parameter values and uncertainties in model cal-culations, and confirming the appropriateness of the model for a spe-cific disposal system will be discussed. The advantages and limita-tions of using specific test methods to address particular information

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 97

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania98

needs will be discussed, and an approach for developing testing pro-tocols for other waste form materials used to immobilize radioactivewastes will be presented. The importance of standardized test proce-dures, including identification of bias and uncertainty in the method,and the need for standard test materials will be emphasized.

9:20 AMApplication of Leaching Tests in the Investigation of Long TermBehaviour of HLW Waste Glass: The French Experience (Invited)S. Gin*, CEA, France

In France, long-term behaviour of HLW glass and safety calculationsare based on the predictive and mechanistic model. Still now, accept-ance criteria of waste packages in the geological disposal have notbeen defined. In such a context, leach tests are used for at least 25years from small samples to glass blocks at scale 1 in two differentways: i) understanding the key mechanisms that control the glass dis-solution and establishing the relations between mechanisms and ki-netic regimes, and ii) measuring dissolution rate as function of envi-ronmental parameters (pH, Eh, T, solution composition,radioactivity, etc.). In this presentation, we are going to highlight thathow the first approach combining leach tests, solution analysis andsolid characterization at different scales allows the development ofmechanistic models and how the standard protocols are used for theparameterization of the model.

10:00 AMAccelerated Weathering of Waste Glass at 90°°C with thePressurized Unsaturated Flow (PUF) Apparatus: Implications forPredicting Glass Corrosion with a Reactive Transport Model(Invited)E. M. Pierce*, D. H. Bacon, Pacific Northwest National Laboratory, USA

The interest in the long-term durability of waste glass stems from theneed to predict radionuclide release rates from the corroding glassover geologic time-scales. Several accelerated test methods have beendevelop to observe various aspects of the glass-water reaction. Cur-rently, the PUF test is the only method that can mimic the hydraulicproperties expected in a disposal facility and simultaneously moni-toring the glass-water reaction. PUF tests are being conducted to ac-celerate the weathering of glass and validate the model parametersbeing used to predict the long-term behavior of glass. Results from 1-D calculations with the STORM computer code can accurately pre-dict the concentration of glass components exiting these PUF experi-ments. These results illustrate the importance of integratingexperimental results with reactive transport models to estimate ra-dionuclide release.

Environmental & Energy Issues: EnergyMaterials

Energy StorageRoom: 327Session Chair: Wayne Huebner, Missouri University of Science andTechnology

8:00 AMNanostructured Dielectric Ceramics for High Energy DensityCapacitors (Invited)F. Dogan*, S. Chao, Missouri University of Science and Technology, USA

High permittivity and high electrical breakdown strength (BDS) ofdielectric materials result in increased stored energy density. TiO2, alinear dielectric material, was selected as the higher energy densitycandidate for its high BDS (~350kV/cm) and relatively high permit-tivity (εr: ~110), closely matching εr=80 of water. BDS is affected bydensity, grain size and defect chemistry of the dielectrics. Materialswith nanocrystalline microstructure is stimulating interest across sci-entific disciplines because of its novel physical and chemical proper-

ties. Nanostructured dense TiO2 ceramics exhibit a high grainboundary area and lower concentration of impurities within thegrain boundaries resulting in relatively high electrical breakdownstrength (~1800 kV/cm). The objectives of this work are to developnanostructured dielectric materials with improved performance forhigher energy density applications and to study the influence of thegrain size on the electrical breakdown strength of dielectrics.

8:20 AMCrack-free Antiferroelectric PLZT Thin Films on Base MetalNickel Foil for Embedded High-Energy-Density CapacitorsD. Kwon*, Korea Aerospace University, South Korea; M. Narayanan, B. Ma, U.Balachandran, Argonne National Laboratory, USA

Antiferroelectric film-on-foil capacitors were fabricated for high en-ergy density with volumetric efficiency. AntiferroelectricPb0.92La0.08Zr0.95Ti0.05O3(PLZT, 8/95/5) thin films were de-posited on LaNiO3 buffered base metal nickel foil using chemical so-lution deposition method. Microcracking, which has been one of themain challenges in antiferroelectric PLZT thin film deposition, wassuccessfully avoided by using base metal nickel substrate. Antiferro-electricity of the PLZT film was confirmed by electrical and struc-tural analyses. The fabricated film-on-foil capacitor exhibited excel-lent performances including large energy storage capability (energydensity), high capacitance and reliability, which are essential capaci-tor specifications for pulsed-power and/or power electronic applica-tions. The antiferroelectric film survived under large DC bias withoutbreakdown up to 1.28 MV/cm of electric fields and provided high en-ergy density of 15 J/cm3.

8:40 AMThermodynamic Calculations of Metal-Hydrogen SystemsU. R. Kattner*, NIST, USA

The thermodynamic properties of phases in metal-hydrogen systemsdetermine whether a reaction is possible and whether the reaction isreversible. Thermodynamic modeling using the Calphad method in-corporates experimental and first principles results into an overall T-P-X framework. For multicomponent systems descriptions of theconstituent subsystems are combined to describe the system. Truemulticomponent intermediate compounds require develment of anew thermodynamic description. One major challenge for develop-ing such a database is the general lack of reliable data for many of theconstituent subsystems. Although experimental data can be supple-mented by data from first principles calculations, these data need alsoto be evaluated. The existing thermodynamic database for light-ele-ment hydride systems has been refined and expanded to include de-scriptions of the higher order phases formed by these elements. Cal-culations of the reaction paths for thehydrogenation/dehydrogenation of these materials will be presented.

9:00 AMSorption/desorption properties of MgH2-oxide compositeprepared by ultra high-energy planetary ball millingY. Kodera*, N. Yamasaki, J. Miki, M. Ohyanagi, Ryukoku University, Japan; S.Shiozaki, S. Fukui, Kurimoto, LTD , Japan; J. Yin, T. Fukui, Hosokawa PowderTechnology Research Institute, Japan

The metal hydride-oxide composite of MgH2 with 50wt% Al2O3,NiO, MgO and Nb2O5 was prepared by mechanical grinding (MG)process with ultra high-energy planetary ball mill for a short time.Conventionally, planetary ball mill, in which a belt transfers the driv-ing power to the vial, had been used for 20 to 200 h in order to im-prove hydrogen sorption/desorption properties of MgH2 system.However, ultra high-energy planetary ball mill with a gear wheel wasselected. The influence of gravitational acceleration (GA) during MGon those properties was significant. The MG process for 10 min with150 GA made MgH2 to have the particle size of tens of nano-metersand homogeneous distribution with oxides. When the specimenswere heated with 5K/min under vacuumed atmosphere, the desorp-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 98

Tues

day

AM

www.matscitech.org 99

tion temperature of MgH2 with 50wt% Al2O3, NiO, MgO and Nb2O5was 220, 220, 240 and 230°C, respectively.

9:20 AMDestabilization of LiBH4/LiNH2 with MgH2/Nb2O5 for HydrogenStorage ApplicationsM. U. Jurczyk*, S. Srinivasan, A. Kumar, E. Stefanakos, Y. Goswami, Universityof South Florida, USA

The present work addresses the grand challenge of hydrogen storageby mechano-chemically milling LiBH4 with LiNH2 to produce a newcomplex material. While LiBH4 and LiNH2 are able to store 18.5 wt%and 8.77 wt% hydrogen, respectively, the temperature required to re-lease the hydrogen is too high for practical applications. The newcomplex structure is able to release hydrogen at moderate tempera-ture of about 250 °C. The destabilization of these new complex hy-drides using MgH2 combined with the catalytic improvement ofNb2O5 or combinations thereof is investigated and optimized to fur-ther improve the hydrogen storage performance. The as-synthesizedmaterials are characterized using XRD, FTIR, DSC, TGA andTPD/TPR techniques. The hydrogen sorption behavior of these ma-terials is measured using a Sievert’s type apparatus. The addition ofMgH2 and Nb2O5 shows significant improvement by lowering thedesorption temperature to as low as 125 °C with a capacity of around6 wt% H2.

Other Energy Materials IRoom: 327Session Chair: Fatih Dogan, Missouri University of Science andTechnology

10:00 AMStructure of Water: The World’s Most Important and Plentiful TwoPhases (Invited)R. Roy*, Pennsylvania State University, USA

The significance of water to life, including humans and human soci-ety and human technologies, and including energy, surpasses by or-ders of magnitude that of any of the materials that MST memberswill ever work with. Yet by and large, water has been left largely tochemists to study, and neglected by materials researchers. This paperfocuses on the materials science contribution to the structure andstructure-property relations of water and ultradilute aquasols. Itstarts with an introduction to the 2008 version of the MST view ofthe structure of water. It then reports on some radically new discover-ies and the glaring gaps in our fundamental condensed matter scienceof water. The “black holes” in the materials science as we have learnedand taught it, include: truncation of the number of intensive variablesin our thermodynamics textbooks from P, T, E, & H, to P & T and theremarkable influence of radiation (acoustic and EM) on matter at therare frequencies which cause resonance in the system at various levels(down to nuclear?).

10:40 AMConversion of Soderberg into Prepacked Anode Cells atEgyptalum: Less Energy and Cleaner EnvironmentS. El-Raghy*, Cairo University, Egypt; S. Abd-Elwahab, Aluminum Companyof Egypt, Egypt

This paper presents an overview of effort at Egyptalum to minimizeenergy consumption and perflourocarbons (PFC) emissions by con-verting electrolysis cells from Soderberg into better controlled pre-backed cells. This has gone through learning by doing jointly betweenEgyptalum and Cairo University. University team was responsible ofmathematical modeling of electromagnetic and thermal besides pre-senting the basic design of the proposed cell. The company put thedetailed design, local manufacturing and operating the prebaked ex-perimental cells. The proven design was adopted in a new line and toreplace the old ones. Four prebaked lines, each comprises 96 cells, are

now in operation while two old soderberg lines are still to be con-verted. A real life comparison between the two technologies operatingat the same place is presented in this paper. Electric Energy consump-tion is 15-20% less green-house gases both CO2 and PFC have beenreduceded by 25%.

11:00 AMMicrostructure-property relationships in diesel particulate filter(DPF) substratesA. Shyam*, E. Lara-Curzio, T. R. Watkins, Oak Ridge National Laboratory, USA

Current diesel particulate filter (DPF) technologies depend onporous ceramic structures to trap particulate matter in the diesel en-gine exhaust gas stream. The elevated temperature, 20 – 1000 deg Cel-sius, microstructure-property relationships for porous cordierite willbe presented. The unique temperature dependence of the thermal ex-pansion, elastic modulus and fracture behavior is explained by themicrostructure of porous cordierite. A materials selection procedurethat considers the fracture toughness, elastic modulus and coefficientof thermal expansion of the porous substrates to obtain DPFs withhigh thermal shock resistance and optimal mechanical properties willbe described.

11:20 AMFrequency Tunable Piezoelectric Vibration Harvester forStructural Health MonitoringJ. Youngsman*, D. J. Morris, Washington State University, USA; M. J.Anderson, University of Idaho, USA; P. F. Fleig, C. D. Lakeman, TPL, Inc.,USA; D. F. Bahr, Washington State University, USA

Harvesting vibrational energy is an attractive method to supply lowpower structural monitoring systems, as the environment beingmonitored typically provides a source of kinetic energy. Energy gen-erated by these devices can then be stored and used as required forsensor power and wireless signal transmission. This paper describesan easily frequency tunable mesoscale device that generates electric-ity by straining composite polymeric piezoelectric films that supporta proof mass which oscillates from external vibration. The geometryrestricts the strain to membrane stretching rather than bending,which increases bandwidth. Harvested power increases with in-creases in frequency and acceleration. A model is presented that in-corporates the piezoelectric and mechanical materials properties, thedevice geometry, and the electromechanical coupling, and is com-pared with experimental results of an 80 g device that produces sev-eral mWs of power at 1 g acceleration for frequencies from 100 to200 Hz.

11:40 AMFlexible Piezoelectric Fiber-Based Composite for EnergyHarvestingR. B. Cass*, F. Mohammadi, H. Kim, Advanced Cerametrics, Inc., USA

Conventional piezoelectric ceramic materials are rigid, heavy, andproduced in block forms. The low-cost technology, termed the Vis-cous Suspension Spinning Process (VSSPTM) developed by Ad-vanced Cerametrics, can produce fibers that range in diameter from10-1300 mm. When formed into user defined (shaped) composites,the ceramic fibers possess all the desirable properties of ceramics(electrical, thermal, chemical) but eliminate the detrimental charac-teristics (brittleness, weight). The structure of piezoelectric fibercomposite (PFC) is suitable for the devices that need to be embeddedwith flexibility and longevity. These composites are used in sensing,actuation, vibration dampening, and energy harvesting. These com-posites, in the form of bimorph, produced continuous power in 10-20 milliwatt range vibrating at resonance frequency (20-40 Hz) under4 N of force. The vibrations can be harvested 24 hours per day, almostanywhere. These generators are currently used for powering a num-ber of devices.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 99

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania100

Environmental & Energy Issues: Fuel Cells:Materials, Processing, Manufacturing,Balance of Plant and Systems Operation

Novel Fuel Cell Systems: Materials, Operation andApplicationsRoom: 325Session Chairs: Arumugam Manthiram, University of Texas atAustin; Z. Gary Yang, Pacific Northwest National Lab

8:00 AMSimulations of Solid Oxide Fuel Cell Electrodes with ComplexMicrostructures (Invited)H. Chen*, University of Michigan, USA; J. R. Wilson, S. A. Barnett,Northwestern University, USA; S. B. Adler, University of Washington, USA; P.W. Voorhees, Northwestern University, USA; K. Thornton, University ofMichigan, USA

Since electricity generation at the anode of a solid oxide fuel cell re-quires transport of and reactions involving three species (electrons,oxygen ions, and hydrogen gas), the anode performance is highly de-pendent on microstructure of the three phases and of three-phaseboundaries (TPBs). While a finer microstructure results in an in-crease of the TPB length, coarsening during fuel cell operation be-comes a concern, especially because of the desired long-life of fuelcells. We apply a three-phase phase-field model to simulate the coars-ening process, and link it to electrochemical performance usingtransport and electrochemical simulations. A set of three-dimen-sional (3D) microstructures of anodes resulting from 3D reconstruc-tion, comprising of nickel, yttria-stabilized zirconia and pore phases,are used in the simulations. The effect of coarsening on the electro-chemical performance is systematically investigated.

8:40 AMThermal stresses in planar Solid Oxide Fuel Cell (SOFC) as afunction of thermo-mechanical properties of componentmaterialsT. Manisha*, M. Radovic, TExas A &M University, USA; N. Orlovskaya,University of Central Florida, USA

Distribution of mechanical stresses in Solid Oxide Fuel Cell is a com-plex function of geometry, external mechanical loads(if any), temper-ature distribution and residual thermal stresses. Estimation and dis-tribution of thermal stresses as a function of thermo-mechanicalproperties of constituent materials and geometry of planar SOFC cellhave been performed using finite element modeling. Different com-binations of conventional and advanced materials studied in the pres-ent work include YSZ, ScCeZrO2, GdCeO2 as electrolyte, Ni-YSZ, Ni-ScCeZrO2 as anode, and LSM and LaSrCoFeO3 as the cathode.Coefficient of linear thermal expansion and elastic moduli have beendetermined as a function of temperature (30C-900C) in air usingthermal mechanical analyzer and resonant ultrasound spectroscoperespectively. Thus measured thermo-mechanical properties havebeen utilized to estimate and model the distribution of thermalstresses at different temperatures in the cell.

9:00 AMGadolina-Doped Ceria Thin Films Deposited by RF ReactiveMagnetron SputteringY. Kuo*, Tatung University, Taiwan; C. Lee, H. Liang, National TaiwanUniversity of Science and Technology, Taiwan

Gadolina-Doped Ceria (GDC) thin films were prepared by RF reac-tive magnetron sputtering from a Gd-10 at% Ce alloy target in reac-tive O2/Ar gas mixtures and then performed a post-treatment at700°C for 2 hours. Material characteristics and chemical composi-tions of the GDC films were investigated by X-ray photoelectronspectroscopy (XPS), cross-sectional scanning electron microscopy

(SEM), and X-ray Diffraction (XRD). Electrical behaviors were meas-ured by AC impedance between 500~700 °C at OCV for air condi-tion. GDC film microstructure was found to be an assembly of verysmall columnar crystallites with a cubic fluorite structure. The ionicconductivity of GDC was slightly larger than that of bulk yttria-stabi-lized zirconia (YSZ). Our results suggest that GDC thin films can beused as solid electrolyte layers for solid oxide fuel cells (SOFCs) sys-tem as compared to the well-known YSZ.

9:20 AMMicrostructurally Engineered Composite Materials for SOFCElectrolyte ApplicationsA. G. Willsey*, NYS College of Ceramics, USA; V. W. Amarakoon, G. E.DelRegno, Center for Advanced Ceramic Technology, USA

Core-Shell type composite materials were synthesized as 3 mol %Y2O3 stabilized ZrO2 shells over 8 mol % Y2O3 stabilized ZrO2 coresand 8 mol % Y2O3 stabilized ZrO2 shells over 3 mol % Y2O3 stabilizedZrO2 to investigate creating more mechanically durable SOFC mate-rials with ionic conductivity values comparable to those currentlyutilized. SOL-GEL compositions were prepared using zirconia n-propoxide and hydrated yttrium nitrate and particles of Tosoh YZ-3and Tosoh YZ-8 were coated respectively. Precursors were dried, cal-cined, and tape cast before sintering in the range of 1450°C – 1500°Cwas completed. Mechanical testing yielded fracture toughness valuesof 6.64 MPa m1⁄2 - 8.94 MPa m1⁄2. Ionic conductivities of 0.0643 Scm-1

– 0.0712 Scm-1 were achieved, at 1073°K. The interpretation of theseresults and the grain boundary contributions to the ionic conductivi-ties, measured by impedance spectroscopy is examined. SEM imagesindicating grain structure of 250 - 400 nm is presented.

10:00 AMMechanical and Electrochemical Performance of Micro-TubularSOFCs for APU-Applications (Invited)N. M. Sammes*, J. Song, K. Galloway, B. Roy, Colorado School of Mines,USA; M. F. Serincan, University of Connecticut, USA; M. Awano, T. Suzuki,AIST, Japan

The present paper is focused on modeling, mechanical, and electro-chemical properties of the micro-tubular SOFCs and SOFC cubestacks for potential use in an APU-system. To predict microtubularSOFC performance, a two-dimensional model was considered, fol-lowed by the results of mechanical and electrochemical testing. Theattention was paid to the development of materials for electrodes andelectrolytes that lower the operating temperatures to below 650oC, aswell as to the development of manufacturing processes for sub-mil-limeter tubular SOFC cells for arrangement and integration at themicro level. The results of a micro-tubular SOFC, and a cube-typecell stack module are presented. The micro-tubular SOFCs with highenergy efficiency, quick start-up and shut-down performance andlow production cost are described in addition to the mechanicalproperties and fabrication technology data for the SOFC materialsoperating in the temperature range of 450-650°C.

10:40 AMHigh Performance Interleaved Electrolyte Supported Solid OxideFuel CellP. S. Gentile*, S. W. Sofie, Montana State University, USA

Solid oxide fuel cell (SOFC) stacks are based on the planar designconcept to yield high power densities. Montana State Universityhas developed a novel planar electrolyte supported cell (ESC)concept utilizing an innovative design with post ceramic process-ing to effectively lower the ASR of the thick electrolyte whilemaintaining the traditional advantages of the ESC technology.This concept not only makes use of most heavily utilized YSZelectrolytes, but is compatible with all types of novel electrolytematerials. Photo-resist machining and laser drilling of interleavedelectrolyte texture introduced into both surfaces of YSZ greentapes and sintered substrates were investigated. SEM microstruc-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 100

Tues

day

AM

www.matscitech.org 101

tural analysis, mechanical strength testing via concentric ring onring tests and fuel cell performance data will be reported andcompared to an ESC baseline to establish the feasibility of thisconcept.

11:00 AMDevelopment of Passive Air-breathing DMFC with Low CatalystsLoadingY. Lu*, R. G. Reddy, The University of Alabama, USA

A passive, air-breathing liquid feed direct methanol fuel cell(DMFC) with 4 cm2 active area was designed, fabricated, and evalu-ated. In the DMFC, catalysts loading were of 0.5mg/cm2 Pt and 1mg/cm2 PtRu (50:50) on the anode and cathode respectively. Theperformance of the DMFC was evaluated by using several electro-chemical techniques with different methanol concentrations. The re-sults showed that the higher methanol concentration gave lowerDMFC performance may be due to methanol crossover. Themethanol crossover in the passive DMFC reached equilibriumwithin 10 minutes and the open circuit potential of the DMFC ob-tained was about 0.5V. The performance of DMFC was determinedas a function of the methanol transport. The enforced air convec-tions further lowered its performance. Additional studies on the ef-fect of other cell parameters on the performance of DMFC are inprogress.

11:20 AMAchievements in Solid Oxide Fuel Cell (SOFC) Materials andChallengesM. E. Ebrahimi*, SorenTec, Canada

Solid oxide fuel cells (SOFCs) are promising future electricity-generation technology due to their high electrical efficiency. Thetechnology status stands in commercial/research now. Their de-velopments face several issues such as high cost materials and cor-rosion in high operating temperature. One challenge is to develophigh performance electrolyte materials with high oxygen ion con-ductivity at lower temperature. High power density, thermal ex-pansion match with cathode, durability, cost-effectiveness, andelectrical reliebility are among desired goals. This paper reviewsthe status of SOFC with emphasis on recent material develop-ments and challenges to improve electrical efficiency and stabilityof SOFC. New materials for oxygen conducting ceramic elec-trolyte such as doped ceria, and doped lantanium gallat are dis-cussed and compared with traditional doped zirconia. Materialsdevelopment for pervskite chatode, and nickel cermet anode elec-trode are addressed.

11:40 AMUse of Fourier Transformation to Analyse Impedance Responsesfrom Inert Substrate Supported SOFCsG. Reade*, Rolls Royce Fuel Cell Systems Ltd., United Kingdom; Z. Liu, RollsRoyce Fuel Cell Systems (US), Inc., USA; M. Jorger, G. Agnew, Rolls RoyceFuel Cell Systems Ltd., United Kingdom

An impedance analysis method which calculates the distribution ofrelaxation times is used to analyse and understand the impedance re-sponse of inert substrate supported solid oxide fuel cells in hydrogenbased fuels. A range of conditions have been studied including steamand hydrogen concentration and inert substrate thickness. Ordinarilythe impedance response of the inert supported SOFC consists of ahigh and low frequency arc. The Fourier transformation method hasallowed the de-convolution of these two arcs into 5 separateprocesses. The most significant process in terms of polarisation resist-ance is seen at relaxation times of the order of 1 Hz. This process issensitive to pH2 and pH2O and is attributed to gas diffusion in thesubstrate and anode. It is proposed that when hydrogen / steam fuelsare used the substrate has a significant impact on cell losses.

Environmental & Energy Issues: NanoscaleDesign of Materials for Extreme RadiationEnvironments

Irradiation Studies in NanomaterialsRoom: 323Session Chairs: Xinghang Zhang, Texas A&M University; K. Murty,North Carolina State University

8:00 AMIon irradiation damage in nanostructured metallic multilayers(Invited)X. Zhang*, E. Fu, N. Li, Texas A&M University, USA; A. Misra, Los AlamosNational Laboratory, USA

We report on helium ion irradiation damage in sputter-depositedmetallic multilayers. Magnetron sputtering technique was used tosynthesize immiscible Cu/V multilayers with fcc/bcc interface, andmiscible Fe/W multilayers with bcc/bcc interface. In each multilayersystem, individual layer thickness, h, was tailored to be in the range of1 to 200 nm. Evolutions of microstructure and mechanical propertiesof films after radiation will be discussed. Evidence of enhanced radia-tion tolerance was observed in multilayer system. These studies indi-cate that layer interfaces in immiscible systems seem to be effectivesinks for radiation induced point defects, and offer a promising ap-proach to improve radiation tolerance of metallic materials by intro-ducing nanoscale features, such as stable layer interfaces spaced at afew nm length scales.

8:40 AMExperimental atomic scale investigation of irradiation effect inCW 316SS and UFG-CW 316SS (Invited)P. Pareige*, France; E. Auriane, R. Bertrand, Université de Rouen - CNRS,France

Material of the core internals of Pressurized Water reactor (austeniticstainless steels) are submitted to neutron irradiation. To understandthe ageing mechanisms associated to irradiation and propose life pre-dictions of the component or develop new materials, irradiationdamage need to be experimentally investigated. Atomic scale investi-gation of a neutron irradiated CW316 SS with the 3D atom probegives a description of the solute segregation. In order to understandthe mechanism of solute segregation, ion irradiation were also per-formed. These irradiation were realized on a CW 316SS and a nanos-tructured CW 316SS. The studies in a ultra-fine grained (UFG) mate-rial allows first, to easily analyse grain boundaries segregation andsecond, to test the behaviour under irradiation of a new nanostruc-tured material. The three aspects of this atomic scale investigation aretackled in this paper. Comparison is made and efficiency of nanoma-terials under irradiation is discussed.

9:20 AMInfluence of Fast Neutron Irradiation on the MechanicalProperties and Microstructure of Nanocrystalline Metals/Alloys(Invited)W. M. Mohamed*, K. L. Murty, North Carolina State University, USA

The aim of this study is to investigate the influence of fast neutron ir-radiation on both mechanical properties and microstructure ofnanocrystalline materials. Nanocrystalline materials are expected tohave high resistance to radiation damage since the large volume ofgrain boundaries would act as sink for the dislocations produced byirradiation. Mechanical properties of irradiated nanocrystalline sam-ples will be measured using a miniature tensile tester designed spe-cially for that purpose. Developed microstructures of the irradiatedsamples will be studied by TEM. The samples have been already irra-diated and currently under cooling to be ready for handling at lab.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 101

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania102

10:00 AMSmall-Scale Specimen Testing of Irradiated MA 754 and MA 957Alloys (Invited)R. Prabhakaran, University of Idaho, USA; J. I. Cole, D. E. Burkes, J. Gan,Idaho National Laboratory, USA; I. Charit*, University of Idaho, USA

Efforts are currently underway to develop advanced materials for thenext generation nuclear reactors. Microstructural changes due toneutron irradiation have been found to significantly degrade proper-ties of candidate structural materials. Hence, identifying materialsthat can withstand the damage induced by high energy neutrons is ofprime importance. In this study, the effect of neutron irradiation onthe microstructure and mechanical properties of two oxide disper-sion strengthened (ODS) alloys (MA 754 and MA 957) are studied tounderstand the interactions between fine oxide dispersions and radi-ation-produced defects. Mechanical properties are primarily evalu-ated via shear punch testing. Microstructural characterization is per-formed using optical microscopy, scanning and transmissionelectron microscopy. The research is supported by the US Depart-ment of Energy.

Environmental & Energy Issues:Thermoelectric Materials: Science,Technology and Applications

Nanoengineered and Oxide Thermoelectric MaterialsRoom: 324Session Chairs: Terry Tritt, Clemson University; AnkeWeidenkaff, EMPA

8:00 AMNanoengineered Materials for Enhanced ThermoelectricPerformance (Invited)D. Johnson*, University of Oregon, USA

Interleaving materials on the nanoscale presents an opportunity forcontrolling and optimizing the properties of materials. We have dis-covered unprecedented low thermal conductivities for fully densesolids resulting from an unusual balance of order within layers and ashort coherence length between layers. We will discuss the synthesisof many new misfit chalcogenides, consisting of interwoven layers oftransition metal dichalcogenides and metal chalcogenides with rocksalt structures. These new compounds were synthesized by depositingelemental layers followed by low temperature annealing. The thermalconductivities of these properties can be tuned by controlling thenanostructure of the material. Carrier concentrations can be con-trolled via an equilibrium approach based vapor annealing. The in-terplay between carrier concentrations and nanostructure for solid-state isomers at equilibrium with one another will be discussed.

8:30 AMMetal-Semiconductor Nanocomposites for Thermoelectric EnergyConversion (Invited)A. Shakouri*, University of California, Santa Cruz, USA

After a brief comparison of thermoelectric and solid-state thermioniceffects, we describe novel thermo-electric materials based on semi-metallic rare earth nanoparticles in a semiconductor InGaAlAs ma-trix and nitride based metal/semiconductor multilayers. Hot electronfiltering using heterostructure barriers is used to break the trade offbetween high Seebeck coefficient and high electrical conductivity. Inaddition, the embedded nanoparticles and interface layers reduce thelattice thermal conductivity by scattering long and medium wave-length phonons. Measurement of the thermal conductivity, electricalconductivity and Seebeck coefficient are presented as well as the di-rect ZT measurement using the transient Harman technique. Inte-grated circuit fabrication techniques are used to transfer the n- and p-

type 10 or 20 microns thick thin films onto AlN plates and 400 ele-ments power generation modules are fabricated and characterized.

9:00 AMNanocomposites of Bismuth Telluride and C60N. Gothard*, Clemson University, USA; J. E. Spowart, Air Force ResearchLaboratory, USA; T. M. Tritt, Clemson University, USA

Nanocomposites have been produced by incorporating thermoelec-tric bismuth telluride and semiconducting C60 nanoparticles into amatrix of bulk bismuth telluride material via powder blending andhot pressing. The nanocomposite microstructures have been exam-ined by SEM and X-ray powder diffraction. Quantitative assessmentsof porosity as well as nanoparticle phase distribution have been car-ried out. The effects of the different nanoparticles on the ther-mopower, electrical resistivity, thermal conductivity, etc., have beenstudied at room temperature and below. Based on these results, thepotential for improving the figure of merit within the bismuth tel-luride system by improving the distribution of the nanoparticlephases via process modification is considered.

9:20 AMTransmission Electron Microscopy Studies of Nanostructure inββ-Zn4Sb3Ø. Prytz*, University of Oslo, Norway; G. J. Snyder, E. S. Toberer, CaliforniaInstitute of Technology, USA; J. Taftø, University of Oslo, Norway

The origin of the extraordinary low thermal conductivity of β-Zn4Sb3[1] is believed to be caused by disorder and defects at the nanoscale.While the fine details of the crystal structure of this material long re-mained unresolved, structural models have been introduced that sug-gest that the low thermal conductivity is a result of disordered Zn oninterstitial sites in the unit cell [2]. Furthermore, the presence ofnanostructured domains was recently suggested [3]. Transmissionelectron microscopy (TEM) is an ideally suited technique for study-ing nanostructures. We employ electron diffraction and high resolu-tion TEM, and observe deviations from the ideal crystal structure inβ-Zn4Sb3. [1] T. Caillat, J. –P. Fleurial, and A. Borshchevsky. J. Phys.Chem. Solids 58, 1119 (1997) [2] G.J. Snyder et al. Nature Materials 3,458 (2004) [3] H. J. Kim et al. Phys. Rev. B 75, 134103 (2007)

10:00 AMSrTiO3-Based Superlattices for Thermoelectric Energy Conversion(Invited)K. Koumoto, H. Ohta*, Nagoya University, Japan

Undoped SrTiO3/SrTiO3:Nb superlattices were successfully preparedby PLD method and quantum confinement of the two-dimensionalelectron gas (2DEG) was confirmed to show giant Seebeck coeffi-cient, resulting in an estimated ZT of 2.4 at 300 K for one unit celllayer of Nb-doped SrTiO3[1]. This superlattice was found to be stableup to 900 K where Seebeck enhancement due to the quantum con-finement was observed[2]. It has been verified that at least 16 unit celllayers of undoped insulating SrTiO3 are necessary to effectively con-fine 2DEG in a Nb-doped well layer, which leads to degradation ofthe TE performance as a whole[3]. ~5 unit cell layers of BaTiO3 withhigh dielectric permittivity replaced with SrTiO3 were found to beonly necessary for effective quantum confinement. References [1] H.Ohta, K. Koumoto et al., Nature Mater. 6, 129-134 (2007); [2] K. H.Lee, H. Ohta, K. Koumoto et al., Appl. Phys. Express, 1, 015077(2008); [3] Y. Mune, H. Ohta, K. Koumoto et al., Appl. Phys. Lett., 91,192105 (2007)

10:30 AMAtomic Layer Thermopile and Its Application (Invited)H. Habermeier*, MPI-FKF, Germany; P. Zhang, Kunming University ofScience and Technology, China

A new class of thermoelectric thin film material is described, charac-terized by anisotropic Seebeck tensors which is also referred to as

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 102

Tues

day

AM

www.matscitech.org 103

atomic layer thermopile (ALT). Early studies revealed that inYBa2Cu3O7 thin films there appears a voltage when shining lightpulses onto the surface of films which is of thermoelectric origin.Originally, only layered high Tc superconductor oxides have been re-garded as suitable ALT materials, however, a similar effect was discov-ered in quasicubic LaCaMnO3 thin films thus opening a new avenuefor material systems other than high Tc superconductors for such ex-periments. Recently, research revealed that there are quite a numberof complex transition metal oxides which demonstrate ALT proper-ties, such as manganites, cobaltates and nickelates. In this contribu-tion we explore the application potential of the concept of ALT forthermoelectric as well as photon sensing devices and pay special at-tention to designing novel materials with enhanced thermoelectricfigures of merit.

11:00 AMHigh-throughput combinatorial mapping of LaMO3 (M = Ti, Mn,Co, Ni) thin film thermoelectric property diagramsE. L. Thomas*, M. Otani, G. Liu, W. Wong-Ng, National Institute ofStandards and Technology, USA

High-throughput combinatorial mapping is a state-of-the art screen-ing technique for accelerating the selection and introduction of ther-moelectric materials into the manufacturing process. Technologicallyimportant LaMO3 materials have been selected to generate single-crystalline continuous-spread combinatorial thin film libraries,which have been deposited onto 50.8 mm diameter LaAlO3 (100)substrates by short duration KrF excimer laser beam pulses (25 ns) ofhome-grown targets via pulsed laser deposition inside a vacuumchamber with a partial O2 pressure of 13.3 Pa at T = 600 °C. X-raydiffraction and compositional mapping wavelength-dispersive spec-trometry have been employed in the structural/compositional analy-ses of the libraries. The resulting phase diagrams have been correlatedwith measurements of thermoelectric property variations as a func-tion of wafer position using our newly developed high-throughputscreening tool.

11:20 AMThermoelectric Properties of Reduced Rutile TiO2J. Tang*, W. Wang, University of Wyoming, USA; G. Zhao, SouthernUniversity, USA

The thermoelectric properties of reduced rutile TiO2 have been in-vestigated. The results suggest that a high thermoelectric figure ofmerit is possible in the rutile phase of TiO2. Samples were preparedwith solid state reaction in a reducing atmosphere. Relatively highSeebeck S and low thermal conductivity κ are observed at room tem-perature, S = -130 μV/K and κ = 1.35 W/mK. The electrical resistivityof reduced TiO2 decreases to ~0.5 Ω.cm and exhibits an insulator-to-metal transition near 340 K. Further optimization of the sample pa-rameters is possible, so that the results are encouraging. Limited re-duction in the Seebeck S and much reduced thermal conductivity κand resistivity ρ for the reduced rutile TiO2 contribute to the overallperformance of the ZT. Doping with Cr and Mn resulted in loweredSeebeck coefficient S. The thermal conductivity seems not much af-fected by the doping, on the other hand, the resistivity of samples in-creases slightly with the doping concentration.

11:40 AMRoles of Na vacancy on Lowering Lattice Thermal Conductivity inNaxCoO2M. Yoshiya*, T. Okabayashi, M. Tada, T. Nagira, H. Yasuda, OsakaUniversity, Japan

A series of layered oxides including NaxCoO2 are prime candidates forthermoelecric applications. While Seebeck coefficient and electronicconductivity have been extensively studied from both theoretical andexperimental viewpoints, understanding of thermal conductivity isstill limited due to difficulty to obtain enough large single crystal withnegligible small amount of chemical and defect content. In order to

reveal factors that determine the thermal conductivity of NaxCoO2,perturbed molecular dynamics simulation has been carried out withan aid of first principles calculation to analyze further. It is found thatpresence of Na vacancy is responsible for the drastical decrease inthermal conductivity through decreasing contribution of Co-O vi-brations to overall thermal conductivity while their cooperative vi-bration are retained even at high temperature, little disturbing Co-Onetworking responsible for high Seebeck coefficient and electronicconductivity.

Fundamentals & Characterization: CeramicSurfaces, Grain Boundaries and Interfaces

Interface Structure and Properties IRoom: 301Session Chairs: Paul Wynblatt, Carnegie Mellon University;Christina Scheu, University of Munich

8:00 AMMeasuring the Five Parameter Grain Boundary CharacterDistribution From Three-Dimensional Orientation Maps(Invited)S. Dillon, G. Rohrer*, CMU, USA

Combining dual-beam focused ion-beam scanning electron mi-croscopy with electron back-scatter diffraction (EBSD) allows for acomplete description of the macroscopic crystallography of a sample.The grain boundary character distribution (GBCD) is an importantdescription of the grain boundary network that is thought to be a sig-nificant indicator of materials properties. The GBCD is defined as therelative areas of grain boundaries with distinct misorientations andboundary plane normals, and is expressed in units of multiples of arandom distribution (MRD). Serial sections of EBSD data have beencollected and reconstructed in 8% yttria-stabilized zirconia andnickel. Different methods for calculating the GBCD from 3D recon-structed microstructures are compared with a more established stere-ological analysis of 2D data. Implications of the results on under-standing grain boundary networks in polycrystals will be discussed.

8:40 AMInterface Structure/Property Relations through Aberration-Corrected STEM and First-Principles Theory (Invited)S. Pennycook*, M. Varela, K. van Benthem, G. S. Painter, P. Becher, Oak RidgeNational Laboratory, USA; S. T. Pantelides, Vanderbilt University, USA

The aberration-corrected scanning transmission electron microscopewith first-principles theory provides new insights intostructure/property relations. Two examples will be presented. InSi3N4 ceramics, images of additive rare earth atoms segregated tosites on prismatic grain surfaces correlate well with sites calculatedfrom first-principles, explaining the dopant-induced microstructureand improved mechanical properties. The second example concernsthe mechanism whereby Ca dopant improves the grain boundarycritical current in YBa2Cu3O7. In undoped material, the strong re-duction in critical current across a grain boundary is caused by thereduced formation energy for oxygen vacancies at dislocation cores.In a Ca-doped boundary, the improved critical current is because,unlike in the bulk, Ca takes Cu and Ba sites to reduce local stresses.The oxygen vacancy formation energy, and the oxygen concentration,is restored almost to bulk values, improving the critical current.

9:20 AMInfluence of the grain boundaries on the properties of silica dopedzirconia and alumina ceramics (Invited)L. Gremillard*, N. Louet, T. Epicier, J. Chevalier, G. Fantozzi, INSA-lyon,France

The morphology and the composition of glassy phases in doped zir-conia and alumina ceramics are studied for different cooling rates

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 103

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania104

after sintering. Quenched zirconia exhibits silica-rich glassy phasesboth at grain boundaries and multiple junctions, with yttrium andzirconium enrichment. These observations are related to equilibriumat high temperature. Slowly cooled zirconia contains glassy phasesonly at multiple junctions. During specific conditions of cooling, it isthus shown that dewetting can occur, giving rise to a low temperatureequilibrium without glassy phase. In-situ TEM experiments confirmthat hypothesis. Silica-doped alumina presents a somewhat differentbehavior, since even slowly cooled it can retain its high temperatureequilibrium state. At intermediate temperature, silica diffuses in thealumina matrix, and forms silica-rich, glassy phase free grain bound-aries. A higher temperature, the grain boundaries are wetted by aglassy phase.

10:00 AMAtomistic Study of Thermodynamical and Mechanical Stabilitiesof Thin Copper Films on Tantalum (Invited)A. Hashibon*, C. Elsaesser, Y. Mishin, P. Gumbsch, Fraunhofer-Institut fuerWerkstoffmechanik IWM, Germany

The Cu/Ta system is a technologically important FCC/BCC het-erophase interface system, where Ta is used as diffusion barrier toprevent the Cu from interacting with the Si of the chip. The mechan-ical and thermodynamical properties of these interfaces are investi-gated via first-principles density functional theory (DFT) calcula-tions and molecular dynamics (MD) simulations employing aspecially developed Cu-Ta interatomic potential. The DFT calcula-tions indicate that coherent interfaces of thin Cu films on Ta are ther-modynamically unstable. An energy-weighting scheme extending theuse of DFT to large-scale incoherent interfaces, shows that an inco-herent monolayer of Cu on Ta is thermodynamically stable, in agree-ment with the results from the MD simulations. For coverage bymore than a monolayer, the Cu atoms form 3D islands on top of theCu monolayer.

10:40 AMEpitaxial Conversion of Surface Coatings on c-plane Sapphire andMagnesium Aluminate Spinel (Invited)S. Dutta, D. Browne, H. Li, J. Biser, R. Vinci, H. M. Chan*, LehighUniversity, USA

Oxidation heat-treatment of aluminum thin films on c-plane sap-phire can result in epitaxial conversion to form a pristine aluminalayer. Lithographic e-beam patterning of the metallic coatings can beexploited to produce sapphire substrates with nanoscale features,which have potential for achieving reduced defect density in GaN-based devices. For Al coated substrates subjected to solid state anneal-ing (450-650°C) in air, dissolution of the metallic Al film revealed thepresence of hollow, sub-surface oxidation features, formed at the Al-sapphire interface. These 3-D features adopt a truncated pyramidalmorphology, and are oftentimes associated with the formation ofhillocks in the Al film. The mechanism by which these features de-velop will be discussed with respect to the solid state oxygen transportmechanisms in Al. Recent results on the epitaxial conversion of sol-gel derived coatings on magnesium aluminate spinel substrates willalso be presented.

11:00 AMDirect Observation of Strong Interaction between NanosizedMetal Particles and Oxide Surface (Invited)X. Pan*, H. Sun, G. W. Graham, University of Michigan, USA

The interaction between metal particles and their oxide support canbe strong enough to affect the reactivity of a catalyst system, for ex-ample, by encapsulation of the particles by the oxide. Direct observa-tion of metal-oxide interfaces with atomic resolution is a challengeand can only be achieved by cross sectional high-resolution transmis-sion electron microscopy (HRTEM). With this approach, we foundpartial encapsulation of Pd particles by reduced ceria-zirconia in amodel, single-crystal thin film auto catalyst, indicating a strong inter-

action between Pd and the oxide. Besides obtaining HRTEM images,the valence of cerium was determined by electron energy loss spec-troscopy (EELS). The effect of reduction and oxidation conditions onthis interaction provides a qualitative explanation for a previouslyobserved reversible reactivation of oxygen storage in model powderauto catalysts. Similar studies were carried out for other metal-parti-cle-on-oxide systems.

11:40 AMSpace charge in iron doped alumina, grain boundary region ironenrichment,related diffusivityA. Bataille*, A. Mussi, J. Crampon, University of Lille, France

The space charge is studied in iron doped alumina and its relation tosegregation is investigated. The diffusivity of the grain boundary re-gion is improved, as creep experiments show. A space charge poten-tial is calculated. Analytical transmission electron microscopy hasbeen carried out on iron doped alumina. Grain boundary iron en-richment is observed. Iron ions interact with the space charge. Theysegregate in the grain boundary region depending on their valenceand on the space charge. A difference between the strict grain bound-ary and the space charge region has to be introduced. This is com-pared to the experimental observations. Regarding the strict grainboundary a depletion of ferrous iron is proposed, together with anenrichment of both aluminium intertitials and oxygen vacancies.Only the subgrain region shall be enriched with the ferrous iron ex-cess. The diffusivity improvement is associated with the aluminiumintertitials enrichment of the strict grain boundary.

Fundamentals & Characterization: Discoveryand Optimization of Materials throughComputational Design

Ab Initio Approaches for Hydrogen Storage MaterialsRoom: 303Session Chairs: Vidvuds Ozolins, University of California, LosAngeles; Chris Van de Walle, University of California

8:00 AMFirst-Principles Engineering of Materials for Hydrogen Storage(Invited)V. Ozolins*, UCLA, USA; H. Gunaydin, Northwestern University, USA; A.Akbarzadeh, UCLA, USA; E. H. Mazjoub, UMSL, USA; C. Wolverton,Northwestern University, USA; K. N. Houk, UCLA, USA

Hydrogen-fueled vehicles require a cost-effective, light-weight mate-rial with precisely targeted thermodynamics and fast kinetics of hy-drogen release. Since none of the existing metal hydrides satisfy themultitude of requirements for a practical H2 storage system, recentresearch efforts have turned to advanced multicomponent systems.We will show that first-principles density-functional theory (DFT)calculations have become a valuable tool for understanding and pre-dicting novel hydrogen storage materials and understanding theatomic-scale kinetics of hydrogen release. Recent studies in ourgroup have used DFT calculations to (i) predict crystal structures ofnew solid-state hydrides, (ii) determine phase diagrams and thermo-dynamically favored reaction pathways in multinary hydrides, and(iii) study microscopic kinetics of diffusion, phase transformations,and hydrogen release. Research supported by DOE grants No. DE-FG02-05ER46253 and DE-FG02-07ER46433, and by NSF grant No.CBET-0730929.

8:40 AMLinking first-principles simulations and experiments to acceleratethe discovery of novel hydrogen storage materials (Invited)D. Siegel*, Ford Motor Company, USA

For mobile applications in the transportation sector, the demandsplaced upon energy storage media are especially stringent, as poten-

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 104

Tues

day

AM

www.matscitech.org 105

tial candidates for replacing fossil-fuel-powered internal combustionengines (ICEs) —- proton exchange membrane FCs and hydrogen-powered ICEs —- utilize hydrogen as a fuel. Although hydrogen hasthe highest energy density of any common fuel by weight, its volu-metric energy density is exceedingly low. Consequently, the safe andefficient storage of hydrogen has been identified as one of the key sci-entific obstacles to realizing a transition to hydrogen-powered vehi-cles. This talk will present an overview of recent efforts at Ford aimedat developing new materials for reversible, solid state hydrogen stor-age. A tight coupling between first-principles atomistic modeling andexperiments has greatly aided our materials discovery efforts, andseveral examples illustrating the benefits of this combined approachwill be presented.

9:40 AMDehydrogenation Kinetics of NaAlH4 from First-principlesMolecular Dynamics (Invited)B. Wood*, JNCASR, India; N. Marzari, MIT, USA

Among the key challenges for the hydrogen economy is the develop-ment of reliable, lightweight materials for hydrogen storage. Complexlight metal hydrides such as NaAlH4 have garnered interest as poten-tial solutions. However, research progress has been somewhat cur-tailed by a lack of understanding of the relevant reaction pathwaysand dehydrogenation kinetics. We present here the results of our first-principles molecular dynamics investigations of NaAlH4. Our simula-tions have revealed the presence of a hitherto unknown phase transi-tion in the NaAlH4 system which may play an important role indehydrogenation. This transition nucleates at surfaces but is kineti-cally inhibited in the bulk. We have also examined hydrogen trans-port in the presence of point defects to identify atomistic mecha-nisms of ion transport. Implications on understanding the kinetics ofdehydrogenation in NaAlH4 will be discussed.

10:20 AMFirst-Principles Prediction of a Ground State Crystal Structureand Hydrogen Storage Properties of Magnesium Borohydride(Invited)C. Wolverton*, Northwestern University, USA; V. Ozolins, UCLA, USA; E.Majzoub, Univ. of Missouri, USA

Mg(BH4)2 contains a large amount of hydrogen by weight and byvolume, but its promise as a candidate for hydrogen storage is de-pendent on the currently-unknown thermodynamics of H2 release.Using first-principles density-functional theory calculations in con-junction with a newly-developed prototype electrostatic ground state(PEGS) search strategy, we predict a new T=0 K ground state ofMg(BH4)2 with symmetry, which is 5 kJ/mol lower in energy thanthe recently proposed P61 structure. The calculated thermodynamicsof H2 release is within the range required for reversible storage. Wealso predict as-yet-unsuspected intermediate phases in the decompo-sition sequence of Mg(BH4)2.

11:00 AMRole of Defects in Kinetics of Hydrogen Storage Materials(Invited)C. G. Van de Walle*, University of California, USA

First-principles calculations are playing an important role in develop-ing a fundamental understanding of the physics and chemistry of hy-drogen storage materials. In order to accurately describe the mecha-nisms of hydrogen uptake and release, it is necessary to consider theaddition or removal of individual hydrogen atoms. We have per-formed density functional calculations to model the formation of hy-drogen interstitials and vacancies. While the concepts discussed hereare general, they will be illustrated with detailed results for sodiumalanate. We find that hydrogen-related point defects are positively ornegatively charged, and hence their formation energies are Fermi-level dependent - an important feature that has not been recognizedin past studies. This dependence enables us to explain why small

amounts of transition-metal additives drastically alter the kinetics ofdehydrogenation. [Work performed in collaboration with AmraPeles, and supported by DOE and UCEI.]

11:40 AMFirst-Principles Energetics of Solute-Vacancy Binding inMagnesiumD. Shin*, C. Wolverton, Northwestern University, USA

Solute-vacancy binding is a key quantity in understanding diffusionkinetics, and also can have a considerable impact on age hardeningresponse in alloys. However, these binding energies in magnesium arelargely unknown. We have recently demonstrated that first-principlesdensity functional calculations provide a quantitatively accurate pre-dictor of these binding energies in Al, where reliable experimentaldata exists. Here, we use first-principles calculations to compute thesolute-vacancy binding in Mg. For the present work, we select a largenumber of solutes: (i) common solutes in commercial Mg alloys (e.g.,Al and Zn) as well as (ii) elements which have exhibited potential aseffective microalloying elements (e.g., Ag, Ca, and Zr). We analyze thetrends in the binding energies in terms of simply physical features,such as size, valence, and electronegativity of the impurity atoms.

Fundamentals & Characterization: FailureAnalysis for Problem Solving

Fatigue and Fracture IRoom: 304Session Chairs: Mike Stevenson, Engineering Systems Inc.; AaronTanzer, Lehigh Testing Laboratories, Inc.; Dustin Turnquist,Engineering Systems Inc.

8:00 AMFailure Analysis of Torsion Bar in Automotive SuspensionApplicationY. Huang*, Key Safety Systems, Inc., USA

Torsion bars are commonly used in pickup trucks and sports utilityvehicles as the weight bearing springs. A number of torsion bars frac-tured during or soon after the installation in a customer’s assemblyplants. Investigations at several resources concluded that hydrogenembitterment was the culprit. Extensive efforts were directed to avoidhydrogen pickup in the manufacturing process. However, a few barsstill fractured in the same manner afterwards. A review of the applica-tion mechanics indicated that the bars have a high residual tensilestress in the yielded core after pre-setting. When loaded, the higherresultant stress at the core and the discontinuities, which might havepropagated during pre-setting most likely caused the fractures. Thefractograhic evidences obtained from all fractures supported theabove conjecture. Thus the solution to the fractures would be simplyto better controlling the discontinuities in the steel, especially in therange that is yielded during pre-setting.

8:20 AMSmall-Scale Integrated Validation Experiments: Bridging theExperimental-Modeling Gap (Invited)G. T. Gray*, P. Maudlin, L. Hull, S. Chen, Los Alamos National Laboratory, USA

Fundamental and engineering studies of the behavior of materials areconcerned with: 1) quantifying the variation of mechanical proper-ties, such as strength, ductility, and fracture, and 2) developing physi-cally-based models capable of predicting material response for use inlarge-scale code simulations. Robust material models capturing thephysics of high-rate material response are required for large-scale fi-nite-element simulations of complex engineering problems includ-ing: a) automotive crash-worthiness, b) foreign-object damage suchas during bird ingestion in jet engines, c) dynamic structural loadingssuch as an earthquake, d) high-rate manufacturing processes includ-ing high-rate forging and machining, and e) conventional ordinance

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 105

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania106

behavior and armor/anti-armor interactions. In this talk, examples ofsmall-scale validation tests and modeling encompassing increasinglycomplex physical phenomena including constitutive behavior, dam-age evolution and fracture are detailed.

9:00 AMFailure Analysis of Recliner Plates (Invited)E. Ulvan*, Acuren Group, Inc., Canada

Recliners were failing below the expected values during torque to fail-ure testing. Parts are carbonitrided, quenched in oil and then tempered.A sample that failed below the expected value as well as a sample thatfailed at the expected value were submitted for analysis. On the guideplate there was a crack that propagated through the corners of the semi-elliptical sections. In both the guide plate and the tooth plate, marten-site and excessive retained austenite were found. Cracks were intergran-ular. Shear cracks found on guide and tooth plates were transgranular.Cracks generally followed the ferrite phase in the core. Ammonia wassupposedly used as a nitrogen source during the carbonitridingprocess. Results show there were inconsistencies in the heat treatmentprocess. It was suggested that the heat treater alter and closely controlthe heat treatment parameters to eliminate retained austenite in thecase and eliminate the possibility of hydrogen embrittlement.

9:20 AMA Fatal Accident Involving a Glass-Topped Cocktail Table (Invited)A. A. Johnson*, Metals Research Inc., USA; R. J. Storey, University ofLouisville, USA

A partying student fell backwards onto a glass-topped cocktail table. Thetable-top broke into shards, one of which penetrated deeply into his backcausing fatal injuries. The table had an iron frame. Eight small iron tabssupported the soda glass top at the four corners and the mid-points of thefour sides.Two exemplar tables,of which one had tempered glass,and fivesheets of non-tempered soda glass were purchased for study. Tests wereconducted in which a bag of sand was dropped onto a table-top from aheight of 104 cm (41 ins). The untempered exemplar and four of the fivepurchased soda glass sheets all withstood 2.27 kg (5 lb) bags of sand butbroke into shards with 5.54 kg (10 lb) bags. The fifth soda glass sheet wasused to show that it would not break with a 6 lb sand bag but did breakwith a 7 lb bag. The tempered glass sheet could not be broken. A 40 lbsand bag caused the iron tabs to deform downwards and the frame tobuckle slightly. The glass fell through the frame without breaking.

10:00 AMAn Introduction to Fracture Mechanics in Failure Analysis(Invited)J. D. Landes*, University of Tennessee, USA

Fracture mechanics is a technology that is used for insuring safetyand structural integrity in materials and structures. It is defined as atechnology that deals with the effect of defects on the load bearing ca-pacity of materials and structures. The parameter used in a linearelastic fracture mechanics is K, the crack-tip stress intensity factor.Types of failure addressed in a fracture mechanics approach includefailure under monotonic loading, fracture toughness, failure undercyclic loading, fatigue crack growth, and failure under adverse tem-perature and environmental conditions. These can be used to deter-mine design parameters, material requirements and predicted com-ponent life. In cases where these determinations are not adequate, thefracture mechanics approach is also useful in a failure analysis. In thispresentation, a brief background on the fracture mechanics approachis given along with some quantitative examples illustrating the appli-cation of fracture mechanics for the solving of failures.

10:40 AMLarge Press Failures (Invited)R. J. Parrington*, IMR Test Labs Inc., USA; C. Hales, Hales & Gooch Ltd., USA

Several large presses, 5000- to 8000-ton presses, are being used toforge aluminum wheels for medium and heavy truck applications.

Numerous fatigue failures of huge press components have occurred.The fatigue cracks in these cast steel components are often very longand greater than a foot in depth! Sometimes, the cracks are success-fully weld repaired and, at other times, attempted weld repair is un-successful. The size of the failed press components (>50 tons) pres-ents many obvious challenges to the failure analyst. Furthermore,insurance-related litigation poses interesting questions for the expert.This presentation will review details on one or two press failures toaddress these implications.

11:00 AMRoot Cause Analysis for a Flexhose Failure (Invited)D. P. Dennies*, The Boeing Company, USA

This presentation will discuss the root analysis performed on a flex-hose failure fabricated from 321 CRES. The flexhose failure occurredduring qualification testing and was unique in the longitudinal orien-tation of the crack formation. The root cause analysis used a fault treeand failure mode assessment to determine the root cause was a pro-duction process operation which propagated the crack from an in-family process scratch of .001 inch depth through 80% of the wallthickness by mode II shear. This pre-existing flaw caused the earlyfailure by fatigue during the qualification testing. Controlled produc-tion process testing duplicated the longitudinal crack formation andpropagation. It also demonstrated the production process to be moresevere for 1⁄ 4 inch size flexhoses than 3/8 inch size flexhoses.

Fundamentals & Characterization: Fatigue ofMaterials: Competing Failure Modes andVariability in Fatigue Life

Very/Ultra High Cycle FatigueRoom: 305Session Chairs: K. Chan, Southwest Research Institute; J. Larsen, AirForce Research Lab

8:00 AMInfluence of the Metallurgical Instability on the VHCF (Invited)C. Bathias*, University Paris10, France

Initiation of fatigue cracks in the gigacycle regime is often related todefects and flaws located beneath the surface. The effect of metallur-gical microstructure is complicated if a phase transformation occursduring cyclic loading. The reason for that is the high frequency test-ing necessary to get easily the billion of cycles, in a reasonable time.Austenite should be transformed in martensite during cyclic loading.Some other types of instability occur in titanium alloys.All instabili-ties have an effect on the gigagycle SN curve, depending of the R ratioand of the testing temperature. The slope and the shape of the gigacy-cle SN curves depend of the metallurgical instability. In this papersome results coming from steels and titanium alloys are presentedand discussed.

8:40 AMDamage accumulation and fatigue crack initiation in an αα + ββtitanium alloy (Invited)C. J. Szczepanski*, University of Michigan, USA; S. K. Jha, UniversalTechnology Corporation, USA; J. W. Jones, University of Michigan, USA; J.M. Larsen, AFRL/RXLMN, USA

Commercial interest in very high cycle fatigue (VHCF) has beenspurred by the safe-life extension of components in transportationand energy production systems. In the VHCF regime, cyclic plasticstrains are low, fatigue damage is localized, and the propensity forsignificant damage accumulation is highly dependent on the charac-teristics of local microstructures. New techniques have been devel-oped for characterizing VHCF behavior as well as new understand-ing of the role of microstructure-specific fatigue damage

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 106

Tues

day

AM

www.matscitech.org 107

accumulation and small crack growth in fatigue. In this work, ultra-sonic fatigue was used to characterize the VHCF behavior of Ti-6246and three categories of crack initiation sites are observed. Examina-tion of the initiation sites indicates that crystallographic texture suit-able for basal slip is present within these critical microstructural lo-cations. Insights into the process of fatigue crack initiation thatconsider the role of textured regions in damage accumulation will bediscussed.

9:20 AMEffect of Alumite Treatment on Long-life Fatigue Behavior ofAluminum Alloy in Rotating BendingY. Nakamura*, T. Sakai, Ritsumeikan University, Japan; H. Hirano,Matsushita Electric Industrial Co., Ltd, Japan

Alumite treatment is one of typical surface treatment for alu-minum alloy and it provides oxide layer (alumite) on the surface.The method has been widely used for aluminum alloy because thealumite has some excellent characteristics such as wear resistance,electric resistance and so on. Thus, fatigue tests were carried outfor specimens having two different alumite treatments and withoutthe treatment by means of a dual-spindle rotating bending fatiguetesting machine. Fracture surfaces of all the failed specimens wereobserved by using a scanning electron microscope (SEM), and thefatigue fracture mechanisms were discussed from a viewpoing ofthe fractography paying an attention to the effect of the alumitetreatments.

10:00 AMTransition of Fatigue Failure Mode of High-Strength Steel in VeryHigh Cycle Regime (Invited)K. Shiozawa*, M. Murai, University of Toyama, Japan

The most important result of numerous studies for very high cycle fa-tigue of high strength steels is to exhibit ‘duplex’ or ‘stepwise’ S-Ncurves depending on the fatigue failure modes. Three types of failuremode are usually observed, such as, surface-induced failure, subsur-face-induced failure without and with GBF area around an inclusionat a crack origin depending on the stress amplitude level and lifetime.Transition of the fatigue failure modes was investigated in this paperbased on the experimental results obtained under a tension-compres-sion test using the low-alloy steel, JIS SNCM439. Stress amplitude forthe transition of the failure mode was explained by considering an ef-fect of compressive residual stress in the surface layer and competi-tion of surface crack growth with subsurface one. From the evalua-tion of fatigue life based on the estimation of subsurface crack growthrate from the S-N data, the effect of inclusion size on the dispersion offatigue life was explained.

10:40 AMEffects of vacuum-like environment around interior crack ongigacycle fatigue properties of Ti-6Al-4V (Invited)T. Nakamura*, H. Oguma, Hokkaido University, Japan

Gigacycle fatigue fractures are frequently observed in high strengthmaterials such as high strength steel or Ti alloys, and known as show-ing interior-fractures. Several hypotheses have been presented for thereason of interior-fractures; however, the detailed mechanism is stillunclear. In this study, the environment around interior crack was fo-cused on. When a crack initiates and propagates in a material, freshsurfaces formed during cyclic loading hardly absorb oxygen andother gaseous molecules compared with surface-originating crack. Tosimulate these environmental effects on interior-originating frac-tures, fatigue tests and crack growth tests were conducted in high vac-uum condition, and fracture processes were investigated throughSEM analyses. By comparing the properties with surface-originatingfatigue, the mechanism of interior fractures was discussed from theview point of the lack of atmosphere.

11:20 AMEffects of Laser Peening Treatment on High Cycle Fatigue Propertyof Aluminum Alloy (Invited)Y. Ochi*, University of Electro-Communications, Japan; K. Masaki, OkinawaNational College of Technology, Japan; T. Matsumura, T. Kakiuchi, Universityof Electro-Communications, Japan; Y. Suzuki, University of Electro-Commucations, Japan; Y. Sano, Toshiba Corporation, Japan; T. Adachi, FujiHeavy Industries LTD., Japan

High cycle fatigue tests were conducted in order to investigate Laserpeening tratment without protective coating(LPwC) on the fatigueproperties such as fatigue strength, fracture morphology and surfacefatigue crack behaviors of aluminum alloy A7050 for aircracft struc-tures. As results, the LPwC treatment was effectve for fatigue propertyimprovement of A7050 aluminum alloy, and also, the scatter of fa-tigue lives in the whole regime of LPwC treated alloys became verysmall for comparing with those of the non-treated alloys. The non-treated alloys in the whole regime lives and the LPwC treated alloys inthe shorter lives regime showed the surface fracture mode. On theother hand, the LPwC treated alloys in the longer lives regime near10<7 cycles showed the internal fracture mode. It is assumed that rea-sons of the fatigue property improvement are the worl hardening andthe grain refining in the surface layer of the materials by the LPwCtreatment.

12:00 PMEBSD Investigation of the Crack Initiation and TEM/FIB Analysesof the Microstructural Changes around the Cracks formed underRolling Contact FatigueA. Grabulov*, R. Petrov, Materials Innovation Institute , Netherlands; H. W.Zandbergen, Delft University of Technology, Netherlands

Rolling contact fatigue is VHCF, leading to the cracks formationaround nonmetallic inclusions (Al2O3). The purpose of this study isto describe the crack initiation and microstructural changes aroundfully formed cracks in the hardened and tempered bearing steel. Thispaper presents investigations using combination of TEM, EBSD andFIB, on Al2O3/steel interface. EBSD experiments showed the locationsof microcracks initiation at the interface and around carbides. TEManalyses conducted on the subsurface cracks using precise FIB prepa-ration process showed a difference between the crack (formation ofnanocrystalline ferrite) and steel (tempered martensite). It was con-cluded that the high stresses and loads cause heavy deformationaround inclusions which leads to the multi microcracks initiation. Itwas found the crack growth and microstructural changes are simulta-neous processes as a result of low-temperature recrystallization.

Fundamentals & Characterization:International Symposium on Defects,Transport and Related Phenomena

Defects and Transport Related to Fuel Cells andBatteries IIIRoom: 307Session Chairs: Harry Tuller, Massachusetts Institute of Technology;Tatsuya Kawada, Tohoku University

8:00 AMCation Diffusion in Perovskite Materials (Invited)T. Grande*, NTNU, Norway

Cation diffusion governs a number of important mass transportprocesses during fabrication and operation of high temperature fuelcells and dense gas separation membranes. These mass transportprocesses is particularly important for the long term stability of thematerials in chemical potential gradient. Recently we have thereforeinvestigated the cation diffusion in LaMO3 (M=La, Mn, Ca) materi-als. Diffusion couple experiments have revealed that diffusion of M3+

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 107

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania108

is faster than La3+, which is not expected from structural considera-tions. It was shown that the rate of diffusion is influenced by theoxygen partial pressure and thereby the nature of the defect chem-istry of the materials. Moreover, the correlation of oxygen vacancyconcentration and cation diffusion was shown by recent creep meas-urements. Finally, examples of kinetic demixing and decompositionof perovksite materials in oxygen partial pressure gradients will bepresented.

8:40 AMTransference Number Measurements of Al2O3/Gd-CeO2 NanoComposites for SOFC ApplicationsR. Chockalingam*, S. Chockalingam, E. Doreen, V. Amarakoon, AlfredUniversity, USA

CeO2 electrolytes for SOFC are prone to reduction at lower oxygenpartial pressures; thus showing n-type electronic conductivity reduc-ing the efficiency of the system. A nano-composite structure whichconsists of MnO and CoO doped Al2O3 coated with CeO2 was de-veloped. Gd-CeO2 volume ratio is fixed 1:7 in order to reduce theelectronic conductivity without sacrificing the ionic conductivity.The Al2O3 nano particles were prepared from alkoxides and werecoated with CoO and MnO followed by a second coating of Gd-CeO2 nano particles prepared through chemical synthesis. A Trans-ference number measurement set up was designed, developed andthe electrical properties of nano-composite structure were investi-gated in detail as a function of the temperature. The samples werestudied by combining impedance spectroscopy and ionic transportnumber to investigate the effect of electron carriers to the conductiv-ity mechanism. In particular, n-type conductivity in Al2O3/Gd-CeO2 based electrolytes.

9:00 AMCrystal Structure and Conductivity of Doped Ceria Electrolytes atIntermediate Temperatures (Invited)S. Omar, E. D. Wachsman, J. C. Nino*, University of Florida, USA

The development of a higher ionic conductive solid oxide electrolyteoperating at intermediate temperatures (400–600 °C) is critical forthe realization of portable device based on solid oxide fuel cells(SOFCs). Doped ceria materials show promise owing to their higherionic conductivity, and good thermodynamic stability in the fuel cellworking environment. Our recent experimental results have shownthat the ionic conductivity of Sm0.075Nd0.075Ce0.85O2-δ is 30%higher than that of Gd0.10Ce0.90O2-δ at 550oC. To investigate thecrystal structure of the electrolyte at working temperatures and cor-relate it with the observed conductivity, high temperature XRD wascollected on SmxNdxCe1-2xO2-δ, and other singly doped ceria ma-terials in the intermediate temperature range. In addition, to furtherexplore the potential of this co-doped electrolyte system, the per-formance of the anode-supported fuel cells usingSm0.075Nd0.075Ce0.85O2-δ as an electrolyte will be discussed.

10:00 AMFrom fundamentals to working devices: examination of nano-ionic materials for next generation solid oxide fuel cells (Invited)H. L. Tuller*, S. J. Litzelman, Massachusetts Institute of Technology, USA

Recently, much excitement has been generated within the field ofnano-ionics, given the expectation that decreasing dimensions couldpotentially lead to breakthroughs in energy conversion and storagetechnologies. While nanostructured electrodes have been imple-mented with success in Li-ion battery technologies, the impact ofnano-ionic materials on solid oxide fuel cells (SOFCs) remains un-clear. In this presentation, the fundamentals of nano-ionics will firstbe introduced, with focus on the effects of nanoscale grain size andfilm thickness. Then, an analysis of practical implications of nano-ionic materials functioning as solid electrolytes and electrodes will be

presented. Important phenomena such as ionic conduction, devicedegradation, and surface reactions will be discussed with respect tothe increasing role of space charge regions in these devices. Implica-tions for future research relating to intermediate-temperature SOFCswill be addressed.

10:40 AMImpedance Study of SrTi1-xFexO3-δδ MIEC Model CathodesW. Jung*, H. L. Tuller, MIT, USA

As a fundamental baseline study for understanding oxygen reductionreaction occurring on mixed ionic electronic conducting cathodes insolid oxide fuel cell, well defined thin film electrode structures andmodel electrode compositions in the system SrTi1-xFexO3-δ (STF)were selected. Here, key parameters such as the magnitudes and ra-tios of the electronic and ionic conductivity could be systematicallycontrolled. The electrode impedance was observed to be independ-ent of electrode thickness and inversely proportional to the square ofthe electrode diameter pointing to surface exchange limited kinetics.Values for the surface exchange coefficient, k, were calculated andfound to be comparable in magnitude to those exhibited by otherpopular mixed conductors, thereby, confirming the suitability of STFas a model mixed conducting cathode material. The observed trendsare discussed in relation to the known defect and transport proper-ties of STF.

11:00 AMEffect of Surface Modification on the Properties of (La,Sr)CoO3Electrode (Invited)T. Kawada*, M. Sase, K. Amezawa, H. Watanabe, A. Unemoto, TohokuUniversity, Japan; Y. Uchimoto, Kyoto University, Japan

Oxygen exchange reaction was investigated on (La,Sr)CoO3 filmelectrode to clarify the effect of surface morphology and composi-tion. A dense film of La0.6Sr0.4CoO3 was fabricated by PLD and itssurface was modified with a porous layer of (La,Sr)2CoO4. The ap-parent reaction rate was much faster than the single phases ofLa0.6Sr0.4CoO3 and (La,Sr)2CoO4. It was consistent with our previ-ous results of oxygen isotope exchange / SIMS imaging analysis onthe model interfaces. High temperature in-situ micro XAFS was per-formed to investigate the electron structure around the interface ofLa0.6Sr0.4CoO3 and LaSrCoOr4. The Co k-edge XANES suggestedthat the average valence of Co in LaSrCoO4 around the interface wasdifferent form the bulk. It behaved rather like the cobalt in theLa0.6Sr0.4CoO3 phase. The kinetics of the performance enhance-ment will be discussed.

11:40 AMElectrochemical Characterization of Highly Oriented CeriaThin FilmW. C. Chueh*, S. M. Haile, California Institute of Technology, USA

Electrochemical impedance spectroscopy was performed on highlyoriented Sm0.15Ce0.85O1.925 (SDC) thin films onY0.08Zr0.92O1.96 (YSZ) single crystal wafers, under O2-Ar and H2-H2O-Ar atmospheres and at temperatures of 500 - 650 °C. The denseSDC films (~ 1 μm) were grown via pulsed-laser deposition, and theirorientations matched the out-of-plane crystallographic orientationsof their respective (1 0 0), (1 1 0), and (1 1 1) substrates. Furthermore,the films retained excellent adhesion to the substrate after thermal cy-cling to 900 °C. Impedance measurement of the Pt | SDC | YSZ | SDC| Pt cell, through which electron transport is blocked at the SDC | YSZinterface, permits a high precision determination of the gas electroderesistance without complications due to mixed conducting effects.The temperature and gas partial pressure dependences of the elec-trode interfacial resistance showed some deviation from earlier poly-crystalline results, presumably due to substantial differences in sur-face morphologies.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 108

Tues

day

AM

www.matscitech.org 109

Fundamentals & Characterization: Micro-and Nano- Mechanical Behavior of Low-Dimensional Structures and Materials

Micro- and Nano- Mechanical Behavior of Materials -Metallic Materials IIRoom: 308Session Chairs: Juergen Biener, Lawrence Livermore NationalLaboratory; Qiuming Wei, University of North Carolina at Charlotte

8:00 AMDislocations nucleation and starvation in metallic nanowires(Invited)S. X. Mao*, U. Pittsburgh, USA

Nanowires (NWs), owing to their small length scale and high surfacearea/volume ratio, exhibit unique mechanical properties as comparedwith their bulk. In NWs, the free surface will act as both dislocationnucleation and sink source. The dislocation activities are determinedby the length-scale competition between the NW diameter d and thedislocation splitting distance. It’s been found the mechanical defor-mation behaviors of single-crystalline nickel nanowires are quite dif-ferent from their large size with MD simulation. A sequence of com-plex dislocation slip processes results in dislocation starvation,involving dislocation nucleation, propagation and finally escapingfrom the wire system, so that the wires deformed elastically until newdislocation generated. This alternating starvation of dislocations isunique in small-scale structures.

8:20 AMMechanical Properties of High-Pressure Torsion ProcessedNanocrystalline Tantalum by Micro-compression andNanoindentation (Invited)B. E. Schuster, US Army Research Lab, USA; Q. Wei*, UNC-Charlotte, USA;L. J. Kecskes, US Army Research Lab, USA; R. Z. Valiev, Ufa State AviationTechnical University, Russian Federation

By far, the primary research efforts in understanding mechanical be-havior of nanocrystalline (NC, grain size d<100nm) materials havefocused on face-centered cubic metals. Little has been known aboutnanocrystalline body-centered cubic (BCC) metals. In this work, wehave produced NC tantalum, a BCC metal with high melting point,using high-pressure torsion. The smallest grain size in the processeddisks is ~40 nm. We have investigated the mechanical properties ofthe NC Ta in terms of strength, strain rate sensitivity, and so on usingmicro-compression and instrumented nanoindentation. Extraordi-nary mechanical behaviors of the NC tantalum have been observed,including very high yield strength, reduced elastic modulus, and in-creased strain rate sensitivity in comparison to the coarse-graincounterparts. Such observations are in good agreement with recentmolecular dynamic simulations (Z. Pan, Y.L. Li and Q. Wei, Acta Ma-terialia, in press).

8:40 AMMechanical deformation of arrays of carbon nanotubes forcontact swtichesD. F. Bahr*, R. Johnson, S. Mesoravic, Washington State University, USA; J.Jiao, Portland State University, USA

Carbon nanotube turfs, nominally vertical and intertwined withmany contacts, are interesting materials for thermal and electricalcontact switches. The behavior of the turf, while highly anisotropic,shows unique behavior due to weak bonding between the ex-tremely strong one dimensional units. In this presentation wedemonstrate the mechanical and electrical performance of the turfsas a function of subsequent processing, including plasma treat-ments and metallization. The turfs are compliant, show substantialadhesion to a variety of materials, and have non-linear elastic de-

formation. We present both experiments and models of the contactbehavior using both nanoindentation and flat punch deformation.Buckling stresses on the order of 10% of the tangent modulus (10-20 MPa) are described. Electrical switching performance is docu-mented showing no substantial degradation below the bucklingthreshold.

9:00 AMQuantitative Correlation between Nanoindentation Hardness nearGrain Boundaries with PFZ and Macroscopic MechanicalProperties in Al-Zn-Mg (-Ag) AlloysT. Ogura*, A. Hirose, Osaka University, Japan; T. Sato, Tokoy Institute ofTechnology, Japan

The quantitative correlation between nanoindentation hardnessnear grain boundaries with precipitate free zones (PFZ) and macro-scopic mechanical properties was evaluated for Al-Zn-Mg(-Ag) al-loys using nanoindentation test, transmission electron microscopy(TEM) and tensile test. The hardness within PFZ was lower thanthat inside grains, with a tendency of a gradual decrease in hardnesseven outside PFZ in the Al-Zn-Mg (base) alloy. The hardness resultswell corresponded to the composition profiles of solute atoms de-tected by EDX analysis. The hardness was maintained up to closerregions to grain boundaries by Ag-addition due to the smaller widthof PFZ. Furthermore, the elongation under the same level of proofstress was larger in the Ag-added alloy. The hardness difference cal-culated from the obtained hardness of grain interiors and PFZ en-ables to interpret rationally the corresponding elongation and frac-ture mode changes.

9:20 AMSputter-deposited single-crystal like Cu films with nanoscalegrowth twinsO. Anderoglu, X. Zhang*, Texas A&M University, USA; A. Misra, Los AlamosNational Laboratory, USA

Our previous studies have shown that sputter-deposited polycrys-talline Cu films have an average twin spacing of a few nm, mostly ori-ented perpendicular to growth direction. These nanotwinned poly-crystalline films have high hardness, exceeding 3 GPa, but relativelylow conductivity. In this study, we report on new attempt to synthe-size single crystal Cu films to enhance the conductivity while main-taining high hardness. These sputtered Cu films have single-crystallike microstructures (confirmed by XRD) together with very highdensity of growth twins as indicated by TEM studies. The hardness ofthese Cu films exceeds 2.5 GPa, and conductivity of films is very closeto that of bulk high purity Cu.

10:00 AMNanomechanical Characterization of Nanoscale Al/SiCMultilayered CompositesD. Singh*, N. Chawla, Arizona State University, USA; G. Tang, Y. Shen,University of New Mexico, USA

Layered metal-ceramic composites at the nanoscale have a good com-bination of stiffness, strength, and hardness. In this talk, we report onthe deformation behavior of Al/SiC nanolaminates fabricated byphysical vapor deposition (magnetron sputtering). Microstructuralcharacterization was carried by scanning electron microscopy and fo-cused ion beam techniques. The mechanical properties, i.e., Young’smodulus and hardness were evaluated using nanoindentation. The ef-fect of viscoplastic behavior of the aluminum layers on indentationbehavior and response was studied. In particular, the influence of vis-coplasticity on measured modulus and hardness was elucidated. Al-ternative strategies for accurate extraction of these properties will bediscussed. Finally, finite element modeling was conducted to simulatedeformation during indentation and relate it to the experimentally-observed behavior.

001_271.MST_Abstract.4th 9/3/08 3:06 PM Page 109

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania110

10:20 AMIn-situ Observation of Uniform Tensile Deformation of As-quenched Martensitic Steel in SEMY. Ishimoto*, S. Nambu, M. Michiuchi, J. Inoue, T. Koseki, The University ofTokyo, Japan

Uniform tensile deformation of as-quenched martensitic steel was in-vestigated by in-situ observation in SEM. Sandwich specimen whichconsists of high strength low-carbon steel and ductile austeniticstainless steel was prepared. In the sandwich specimen, as-quenchedmartensitic steel can be elongated uniformly over 50% of strain inspite of the fact that the elongation can not exceed 5% of strain in amono-layer. Tensile test of the sandwich specimen was performed inSEM and slip-band formation was observed in-situ. The correlationbetween crystal orientation and slip-band formation was investigatedby EBSP analysis. Ferritic steel, bainitic steel and tempered marten-sitic steel, which were prepared from the same material by furnace-cooling, air-cooling and tempering respectively, were observed in thesame way to clarify the effect of microstructure. Compared withother microstructure, the deformation characteristic of as-quenchedmartensitic steel is clarified.

10:40 AMCorrelation of the Roping Defect with Texture Evolution inAluminum SheetsS. Tiwari*, R. K. Mishra, General Motors R&D Center, USA; S. Hartfield-Wunsch, GM Manufacturing Engineering, USA

The development of roping defects, also referred to as paint brush lines,in strained aluminum sheet materials is investigated using mechanicaltesting, metallography and electron backscatter diffraction analysis(EBSD). It is shown that even though roping defects are a surface rough-ening phenomenon, initial surface roughness of the sheet does not influ-ence their formation. Roping lines readily form in sheets that have alower Lankford parameter in the longitudinal direction than that in thetransverse direction. The microstructure, especially the initial textureand its evolution during straining, correlates well with the formation ofroping defects. Sheets exhibiting no roping defects tend to have a highcube texture component initially and the texture does not evolve signifi-cantly during straining. Texture evolution in sheets exhibiting the ropingdefect shows a rotation of the initial texture towards a cube orientation.

11:00 AMInfluence of Cooling Rates Imposed by Rapid SolidificationTechniques on the Characteristics of NiTi Shape Memory AlloysA. C. Kneissl*, K. Mehrabi, University of Leoben, Austria; M. Bruncko,University of Maribor, Slovenia; D. Uhlenhaut, ETH Zurich, Switzerland

This study investigated the influence of increasing cooling rates onmicrostructure and properties of NiTi alloys. The rapid solidificationof these alloys was achieved by arc-melting with a water-cooled cop-per crucible, melt-spinning and splat-cooling. All three techniqueshave resulted in the successful formation of alloys exhibiting shapememory effects even without subsequent heat treatment. The shift ofthe phase transformation temperatures caused by rapid solidificationwas small, and thus the transformation itself is not greatly influencedby the rapid solidification process. However, due to the differentrapid solidification methods, the size and morphology of microstruc-tures are significantly altered. The microstructures of the sampleswere examined by transmission and scanning electron microscopy,and the shape memory effect of samples was studied by differentialscanning calorimetry, X-ray diffraction and tensile tests.

11:20 AMInfluence of different testing parameters on Scratch Test results ofa coating-substrate systemG. A. Marques*, J. A. Araujo, S. A. Pereira, MAHLE, Brazil

This paper evaluates the influence of different testing parameters onthe adhesion strength of a coating-substrate system, measure throughScratch test. Information about the adhesion strength of a coating-

substrate system can be related to the coating performance. The coat-ing-substrate system herein analyzed is typically used in piston ringsfor heavy-duty diesel engines. It is a Chromium Nitride based layerdeposited over steel by Physical Vapor Deposition process, with aver-age thickness of 30 μm. The main features evaluated were critical loadand failure mode. For each set of parameters it was made a simulationof the applied load to the sample by the indentor. Results showed thatdifferent parameters can cause different failure modes and evenchange results from no failure to failure. This investigation was effec-tive on the definition of best practices for the analysis and compari-son of PVD wear resistant hard coatings for use on piston rings.

11:40 AMMicromechanisms of Deformation Behavior in LiNbO3 SingleCrystal Studied by Spherical NanoindentationS. Basu*, A. Zhou, M. W. Barsoum, Drexel University, USA

Lithium niobate is an important nonlinear optical solid used in elec-tro-optic, acousto-optic, and optical storage devices. In this presenta-tion, the deformation behavior of a LiNbO3 single crystal loadedalong [0001] is explored using spherical nanoindentation stress-strain analysis. Because of its high c/a ratio, the deformation ofLiNbO3 is confined to 2-dimensions and is thus a kinking non-linearelastic solid. The 3-fold symmetry of the indentation marks is attrib-uted to the formation of (10-12) twins that reorient basal planes toallow for basal slip, which is manifested by the formation of large fullyreversible, hysteretic loops upon cyclic loading. The differences in en-ergy dissipation, threshold stresses and loop shapes for 3 different tipradii - 13.5, 5 and 1 μm - are attributed to the different sized twinsthat form. The results are consistent with our model for the formationof dislocation-based incipient kink bands (IKBs) within the twins.

Fundamentals & Characterization: Modelingof Multi-Scale Phenomena in MaterialsProcessing

Microstructure Evolution IIIRoom: 306Session Chair: Nicoletta Popescu Pogrion, National Institute forMaterials Physics

8:00 AMMicrostructural Evolution of Two Phase Al-Li AlloysB. Pletcher*, University of Florida, USA; K. Wang, Florida Institute ofTechnology, USA; M. Glicksman, University of Florida, USA; J. Lebeau,University of California, Santa Barbara, USA

Phase coarsening in overaged Al-Li alloys is a diffusion-controlledprocess. Large particles grow by dissolution and mass transfer fromsmaller particles. Eight binary Al-Li alloys were aged for times between3-240 h, to yield various distributions of δ’ (Al3Li) precipitates. Trans-mission electron microscopy was used to image 10-100 nm diameter,spherical δ’ precipitates via centered dark-field techniques. TEM im-ages were then autonomously analyzed using a novel Matlab® functionto process and provide good statistical 3D results. Computer analysisprovides objective characterization and fast image processing, allow-ing practical access to larger sample sizes. Results, including the parti-cle size distribution and maximum particle size, agree with predictionsfrom diffusion screening theory and a multi-particle diffusion model.

8:20 AMAmplitude-Equation Formulation for Phase Field CrystalModeling in the Two-Phase Coexistence RegionD. Yeon*, University of Michigan, USA; Z. Huang, Wayne State University,USA; K. Elder, Oakland University, USA; K. Thornotn, University ofMichigan, USA

The phase field crystal (PFC) model describes the dynamics of thelocal atomic density in a material on atomic length and diffusive time

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 110

Tues

day

AM

www.matscitech.org 111

scales. The PFC approach has recently attracted attention due to itsability to include elasticity, defects and atomic orientations implicitly,but the small grid spacing for the atomic length scale makes large-scale simulations computationally challenging. The renormalizationgroup approach for PFC has been proposed to overcome this limita-tion, but it had been only applicable to the solid one-phase region ofthe phase diagram. We will present the amplitude-equation formula-tion for PFC (AEF-PFC) to be also applied to evolutions of systems inthe two-phase coexistence region with significantly improved com-putational efficiency. We will discuss differences among AEF-PFC,PFC and the standard phase-field model, and present the simulationresults for crystal growth, coarsening and grain growth of 2D hexago-nal and 3D BCC structures using AEF-PFC.

8:40 AMCan Deformation-Induced Surface Roughness Reliably PredictStrain Localization? (Invited)M. R. Stoudt*, J. B. Hubbard, National Institute of Standards andTechnology, USA

The inability to reliably model the evolution of surface deformationgenerated during sheet metal forming is a key obstacle to the exten-sive use of new alloys in auto bodies. Limiting strains are determinedwith complex deterministic numerical simulations that do not con-sistently predict true localization strains. Since deformed surfaces arecharacteristic amalgams produced by the active mechanisms under aspecific set of mechanical conditions, detailed surface characteriza-tions directly quantify the deformation conditions that promotestrain localization. High-resolution 3-D characterizations of com-mercial aluminum sheet surfaces deformed by 3 in-plane stretchingmodes revealed new details about how strain mode and microstruc-ture influence the evolution of plastic deformation and strain local-ization. In addition, this study establishes that strain localization isdominated by stochastic processes that can be reliably predicted withprecise surface roughness measurements and Weibull statistics.

9:00 AMSelf-Assembly of Egg-Type Microstructure during PhaseSeparation in Liquid Droplet (Invited)R. Shi, Xiamen University, China; C. Shen, The Ohio State University, USA;C. Wang, X. Liu, Xiamen University, China; Y. Wang*, The Ohio StateUniversity, USA

The formation mechanism of self-assembled egg-type microstruc-tures produced by atomization from liquid immiscible Fe-Cu alloyswas investigated by computer simulations of phase separation in liq-uid drops using the phase field method. The model accounts self-consistently for spinodal decomposition and coarsening, fluid flowcaused by chemical potential gradient, Marangoni motion caused bytemperature-dependence of the interfacial energy, and collision andcoalescence among the second-phase droplets. Using material param-eters obtained from database and literature and temperature gradientobtained from heat transfer analysis, the simulation results showquantitatively the entire evolution process leading to the egg-type mi-crostructure. The roles played by each of the concurrent phenomenaat different length scales were analyzed and their contributions to theformation of core-shell type microstructures in various materials sys-tems were discussed.

9:20 AMComputational Approach to Microstructure Evolution in RapidSolidification of Laser Dressed Alumina CeramicA. N. Samant*, University of Tennessee, USA; A. S. Sabau, C. A. Blue, OakRidge National Laboratory, USA; N. B. Dahotre, University of Tennessee, USA

An investigation of microstructure evolution during surface modifi-cation of alumina was carried out using a 4 kW Nd:YAG laser. Limita-tions in in-situ temperature measurement during rapid solidificationwere overcome through a computational method based on an inte-grated micro/macroscopic solidification approach. A succinct finite

difference model, based on fundamental non-equilibrium kineticspredicted the microstructures. Inclusion of multiple liquid cells, non-uniform grid spacing and accounting for heat losses due to volatiliza-tion were some of the salient features considered. Within the presentregimes of laser processing, the grain size increased with increasingpower. The numerical simulation results are in good agreement withexperimental results for the grain size. This work provides the funda-mental understanding of the laser modified surface in terms of graingrowth and can be extended to predict the effects in near or non-equilibrium process.

Multiple Length-scale CouplingRoom: 306Session Chair: Lukasz Madej, Akademia Gorniczo Hutnicza

10:00 AMApplication of the Strain Localization CAFE Model to InvestigateExtrusion with Various Die ShapesL. Madej*, Akademia Gorniczo Hutnicza, Poland; P. D. Hodgson, DeakinUniversity, Australia; M. Pietrzyk, Akademia Gorniczo Hutnicza, Poland

Application of the multi scale CAFE model for simulation of thestrain localization in materials during extrusion is presented in thepaper. Extrusion is one of the most important technologies used inthe plastic working of metals. The possibility to obtain the final shapeof products in a single operation is the main advantage. But extru-sion leads to the nonhomogeneous structures and mechanical prop-erties of products mainly due to the existence of the dead zone andstrain localization in the deformation area. Proper design of the ex-trusion dies may lead to reduction of the dead zone. That is the rea-son why the strain localization occurring in the material during ex-trusion in various geometries of the dies, is investigated here.Obtained results of the metal flow predicted by the CAFE method arepresented in the paper. Approach to solve the problem with connec-tion of the CA and FE methods, with respect to the remeshing opera-tions is also presented

10:20 AMRepresentative volume element sizes for the determination ofeffective properties in porous ceramic-metal compositesJ. Johnson*, J. Qu, Georgia Institute of Technology, USA

A three-dimensional stochastic reconstruction method is used torecreate the three-phase composite, Ni-YSZ. The material consists ofductile nickel, brittle YSZ, and a co-continuous distribution ofpores. The digitally reconstructed microstructure is then transferredinto finite element models to obtain the material’s corresponding ef-fective elastic modulus, coefficient of thermal expansion, and ther-mal conductivity. During determination of effective properties theappropriate size of the volume element for each material property isinvestigated. Specific requirements for volume element size are pro-vided and related to the statistical correlation functions describingthe microstructure.

10:40 AMMulti-Scale Characterization of Orthotropic MicrostructuresM. Tschopp*, G. Wilks, J. Spowart, Air Force Research Laboratory, USA

Computer generated microstructures of varying second-phase areafraction (5%-30%), aspect ratio (1-16), and degree of alignment(where the reinforcement major-axis orientation is random, perfectlyaligned, or semi-aligned) are analyzed via the isotropic and direc-tional forms of the computationally efficient Multi-Scale Analysis ofArea Fractions (MSAAF) technique. The impact of these microstruc-ture parameters on the representative volume element (RVE) neces-sary to characterize a microstructure is ascertained with variations inisotropic and directional homogenous length scales, derivative quan-tities of the MSAAF technique. Analysis of these results produces em-pirical expressions for the directional homogenous length scale as a

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 111

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania112

function of area fraction and aspect ratio for the limiting cases of ran-dom and “perfect” second phase alignment. The significance of thiswork is that the change in a microstructure’s RVE is expressed as afunction of particle alignment, area fraction and aspect ratio.

11:00 AMDirectional Multi-Scale Analysis of Area FractionsG. B. Wilks*, Air Force Research Laboratory (GD Inc.), USA; M. A. Tschopp,Air Force Research Laboratory (UTC Inc.), USA; J. E. Spowart, Air ForceResearch Laboratory, USA

The Multi-Scale Analysis of Area Fractions (MSAAF) technique isgeneralized to accommodate directionally-dependent microstructurevariations over multiple length scales. A simple graphical tool for de-termining preferred orientations in a second-phase as a function ofmicrostructure characteristics (aspect ratio, volume fraction, align-ment propensity, etc.) is introduced and used to characterize syn-thetic two-phase, two-dimensional microstructures as well as selectedexperimental data. Asymptotic analysis is used to determine repre-sentative volume element size for cases of general anisotropy as wellas implications for 3-dimensional microstructure characterization.

11:20 AMNumerical Simulation of Annealing of CdSe Quantum Dots forWhite Light LEDsA. S. Sabau*, C. E. Duty, R. D. Ott, G. E. Jellison, Oak Ridge NationalLaboratory, USA

The pulsed thermal processing (PTP) of CdSe Quantum Dots (QD)using a High Density plasma arc lamp. The single layer of CdSe QDwas deposited on sapphire and was encapsulated in an alumina ma-trix. A computational methodology is proposed to understand theenergy transport and annealing of QD material for solid-state light-ing applications. It was found that the energy balance in the systemwas affected by the QD. The QD monolayer of spheres was found toalter the total reflectivity, even though the energy absorbed in QD wasrelatively small. The numerical simulations can be an effective tool topredict the narrow range of processing parameters and dramaticallyreduce expensive trial-and-error procedures while enabling the en-hanced properties of nanostructured materials to be realized.

Fundamentals & Characterization: PhaseStability, Diffusion Kinetics and TheirApplications (PSDK-III)

Microstructural Analysis, Control and Modeling IIRoom: 302Session Chairs: Mark Asta, University of California at Davis; DavidSeidman, Northwestern University

8:00 AMA Theoretical and Atomistic Simulation Study of Solute Trapping(Invited)J. J. Hoyt*, McMaster University, Canada; Y. Yang, East China NormalUniversity, China; M. Asta, D. Buta, University of California, USA; D. Sun,East China Normal University, China

It is well known that the partitioning of solute in the solid phase in-creases above its equilibrium value at high solidification rates. In theKaplan and Aziz continuous growth model of solute trapping, the ve-locity dependent segregation coefficient is expressed in terms of acharacteristic diffusive speed, Vd, which reflects the interplay betweencrystallization rate and atomic transport across the solid-liquid inter-face. In this talk a density functional based description of interfacemobility is extended to the case of binary alloys and an analytic ex-pression for the diffusive speed, and its anisotropy, is derived. Inagreement with experimental findings, the model predicts that Vd isindependent of the liquid diffusivity and decreases as the equilibriumsegregation increases. In addition, molecular dynamics simulations of

solute trapping have been performed on a model Lennard-Jones bi-nary alloy. The velocity dependent segregation coefficient from simu-lation is compared with the model predictions.

8:40 AMDiffuse-interface Simulations of Reactive WettingW. Villanueva*, W. J. Boettinger, J. A. Warren, NIST, USA

A diffuse-interface model that takes into account fluid flow and diffu-sion is used to study reactive wetting, where the substrate can par-tially dissolve into the liquid. The model consists of concentrationand phase-field equations coupled with the incompressible Navier-Stokes equations. For convection-dominated cases with low diffusionparameters, it has been shown that the dynamics of the wettingmatches a known hydrodynamic theory for spreading inert fluids. Inthis talk, an analysis of the effect of diffusion and interface kinetics oncontact angle variation with triple line speed is presented. The effectof diffusion parameters on the evolution of the drop base radius anddepression depth is also analyzed. Finally, preliminary results on theformation of intermetallic in reactive wetting is also presented.

9:00 AMGeneral Treatment of Precipitation in Multicomponent SystemsQ. Chen*, X. Lu, H. Strandlund, A. Engström, Thermo-Calc Software AB,Sweden

Diffusion-controlled precipitation in multicomponent commercial al-loys has usually been treated as one in pseudo-binary or –ternary systems.Steady-state approximation was quite often used and ternary diffusionalinteraction neglected. In this presentation,general nucleation and growthrate equations are introduced for simulating precipitation process inmulticomponent systems.We then apply a new software package that hasbeen developed on the basis of these equations to simulate multi-particleprecipitations in steels where interstitial C atoms diffuse much faster thansubstitutional ones. Comparison between results from the present ap-proach and DICTRA will also be shown for single particle systems.

9:20 AMDiffusion-limited phase growth around crystal defectsA. R. Massih*, Quantum Technologies, Sweden

Precipitation of new phases in crystalline solids is strongly affected bythe presences of elastic fields, which can arise from defects, such as dislo-cation lines, grain boundaries, micro-cracks, etc, prevalent in structuralmaterials. Similarly, when doping electronic materials, it has been ob-served that Cottrell atmospheres, which arise when interstitial atoms in-teract with dislocations, can pin down the dislocations and trap the in-terstitials. In this paper, we treat the problem of diffusion of solute atomsaround defects, especially in the region of screw dislocations. In particu-lar, we express and solve the diffusion equation, in radial symmetry, inan external field subject to a flux balance boundary condition at the in-terface of the new phase. The second-phase growth rate as a function ofsupersaturation and strain energy parameter is evaluated. Moreover, theGibbs-Thomson formula, relating the solubility limit to the precipitatesize is calculated. The results are discussed in light of experiments.

10:00 AMEntropy in Phase Stability and Diffusion Kinetics (Invited)Z. Liu*, The Pennsylvania State University, USA

Entropy is a measure of randomness in a system and the base of thesecond law of thermodynamics and the combined law of thermody-namics. From a macroscopic viewpoint, classical thermodynamicsdefines the entropy as a state function of a system, which multipliedby temperature gives a measure of part of the system’s energy. Whilemicroscopic definition of entropy in terms of statistic mechanics isbased on the number of microscopic configurations that result in theobserved macroscopic descriptions. As temperature increases, role ofentropy in phase stability and diffusion kinetics becomes more andmore dominant with increased number of microscopic configura-tions. In this presentation, our approaches in accessing those micro-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 112

Tues

day

AM

www.matscitech.org 113

scopic configurations based on first-principles calculations will bediscussed along with applications in predicting first- and second-order phase transitions and self and impurity diffusion coefficients.

10:40 AMCellular Microstructures in Directional SolidificationE. Sunseri*, L. Zhang, R. Trivedi, Iowa State University, USA

In directional solidification, when the planar interface is driven be-yond its stability threshold, the perturbed interface reorganizes into aperiodic array of cells. In the cellular array the spacing between thecells and the width of the cells vary within an array. It is shown that aunique shape is obtained when all the cells in an array are rescaled totheir local spacing. The characteristics of cellular interface are investi-gated in Al-Ni, Al-Cu and succinonitrile-camphor systems in which aeutectic interface forms in the intercellular region. Critical experi-ments are carried out in capillary samples in which a single cell isformed so that the variation in cell shape and interface temperaturewith velocity can be characterized accurately. It is shown that the tipundercooling is a function of the solute distribution coefficient. The-oretical models for the shape of the cells and for cell tip undercoolingwill be presented and compared with the experimental results.

11:00 AMKinetic Effect on Multicomponent Phase CoarseningK. Wang*, Florida Institute of Technology, USA

Study of phase coarsening in multicomponent systems is rare. Morraland Purdy developed a general theoretical frame for phase coarseningin n-component alloys. However, all work considered only the effectof solution thermodynamics, and ignored the kinetic effect fromnon-zero volume fraction. Therefore, all studies are valid only in thecase of nanishing volume fraction. When volume fraction is not zero,the interactions among precipitates exist. In contrast to previous the-ory, a diffusion zone for coarsening particle due to nonzero volumefraction is introduced. The evolution equation for multicomponentphase coarsening is derived in a rigorous way in the framework of themaximum rate of dissipation with the constraints of mass and energyconservation. A mean-field theory of multicomponent phase coars-ening will be presented, which includes effects of both multicompo-nent thermodynamics and kinetics from nonzero volume fraction.

11:20 AMComputational modeling of internal oxidationX. Pan*, J. E. Morral, Y. Wang, Ohio State University, USA

The internal oxidation process in an A-B-O model ternary system wassimulated by DICTRA, finite difference, and phase field method. Pre-dictions from the different approaches revealed that a single horncould form in the resulting diffusion path and point toward theoxide. This indicates that a single phase layer of oxide could be pro-duced at the initial oxidation. The horn’s direction and the conditionsunder which the external oxide layer forms will be discussed, alongwith the microstructure predicted by the phase field modeling.

11:40 AMModelling Precipitation Kinetics in a Complex 9-12% Cr SteelB. Sonderegger*, F. Méndez Martín, Graz University of Technology, Austria

A novel multi-component, multi-particle, multi-phase precipitationmodel developed recently is used to predict the precipitation kineticsin a complex 12% Cr steel. These ferritic/martensitic steels are usedfor thermally exposed components in steam power plants and are de-signed to withstand high temperatures and mechanical loads for op-erating times of more than 10 years. Changes in the microstructure,like nucleation, growth and coarsening of precipitates lead to achange in the mechanical properties of the steel and can cause a se-vere drop in the creep resistance. In this work, a physical model basedon the thermodynamic extremum principle is used to predict the pre-cipitation sequence during heat treatment and service. The result iscompared to experimental data determined by transmission electron

microscopy. Despite the complexity of the system, the model provesnumerically stable and relatively modest regarding computational ef-fort. Model performance, predictive capabilities and limitations arediscussed.

Fundamentals & Characterization: PhaseTransformations and MicrostructuralChanges during Sustained MechanicalForcing

Modeling and Simulation Approaches for DrivenTransformationsRoom: 310Session Chair: Rainer Hebert, University of Connecticut

8:00 AMMolecular dynamics simulation of mechanically driven systems(Invited)M. L. Falk*, Johns Hopkins University, USA

Non-equilibrium simulation on the atomic scale has the capability toelucidate interesting physics in materials subjected to shear inducedsliding. In metallic glass shear bands spontaneously nucleate. The result-ing shear flow systematically destroys the short-range order in a quan-tifiable way. Simulations of the mixing at sliding interfaces betweencrystalline metals exhibit a transient disordered layer that appears to re-sult in similar physics at these interfaces. This disordered layer quicklyanneals out when shearing ends, which may make such disordered in-terfaces difficult to detect after the fact. While such simulations have tra-ditionally been limited to high rates of sliding, typically meters per sec-ond, recent advances allow low sliding speeds on order microns or evennanometers per second. These accelerated dynamics methods are beingapplied to simulate nano-scale friction of an atomic force microscopetip in sliding of an oxidized silicon tip on an oxidized silicon substrate.

8:40 AMMolecular Dynamics Simulations of Microstructural Evolutionduring Sliding (Invited)K. Subramanian*, Indian Institute of Science, India; A. Agrawal, The OhioState University, USA

The high strain-rate, strain, stress and temperature experienced nearthe interface leads to strongly driven microstructural evolution dur-ing sliding interactions between ductile metals. The aim of this studywas to gain insights, via molecular dynamics simulations, into theseveral dynamic and interacting phenomena that cause such mi-crostructural changes. Embedded atom potentials were employed forFe-Cu, Fe-Ni & Cu-Ni tribopairs to probe the effect of driving forceon friction and microstructure in clustering, ordering and misciblebinary tribopair systems. The other variables included sliding veloc-ity, crystal orientation and presence of crystal defects. Results per-taining to adiabatic flow localization, dislocation and twin activity,dynamic recrystallization, vorticity and mechanical mixing, materialtransfer and non-equilibrium phase formation will be presented.Comparisons with experiment suggest that such simulations can pro-vide valuable insights that are otherwise inaccessible to experiments.

9:40 AMCrossover from superdiffusive to diffusive mixing in solids forcedby plastic deformation (Invited)P. M. Bellon*, N. Q. Vo, R. S. Averback, University of Illinois, USA; A. Caro,Lawrence Livermore National Lab, USA

We recently showed that the chemical mixing forced plastic deforma-tion in solids can be superdiffusive in some length scale range. Ex-tending an approach widely used in fluid dynamics based on the so-called Richardson’s pairs, here we derive and solve the kineticequation for the evolution of a point source that spreads over time

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 113

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania114

due to sustained plastic deformation. The mixing is found to be su-perdiffusive, with the mean square separation distance betweenmarkers increasing quadratically in time. A simple scaling analysisshows that this superdiffusive mixing crosses over to conventionaldiffusive mixing when the atom separation distances exceed the meanfree path of the carriers of plastic deformation. Molecular dynamicssimulations are performed on crystalline, nanocrystalline and amor-phous alloy systems to test these predictions. We discuss the implica-tions of the scale-dependent mixing for applications such as rolling,ball milling, or during sliding wear.

10:20 AMStress-oriented precipitation of second-phase in alloysL. O. Jernkvist, A. R. Massih*, Quantum Technologies, Sweden

Stress-induced orientation of second-phase particles occurring dur-ing precipitation is ubiquitous in many metallurgical systems. For ex-ample, the precipitation of titanium hydride in titanium and zirco-nium hydride in zirconium alloys indicates that the stress orientationof the hydride platelets occurs through orientation of nuclei ratherthan through growth after the critical nucleus size has been reached.A simple mathematical model for precipitation of the second-phaseunder an applied stress is presented. The model uses a continuum de-scription of the matrix-precipitate system, in which precipitates arerepresented by their local volume fraction, κ and an orientation pa-rameter, θ. The latter expresses the probability of finding a precipitateplatelet aligned in a given direction. Kinetic equations, based on dif-fusion theory and classical nucleation theory, are used to describe thetime evolution of κ and θ. The model is used to describe the stressorientation of δ-hydrides in Zr-alloys in light of experiments.

10:40 AMSignificance and Development of a Next-Generation Level 2 Modelas a Metallurgical SystemB. Li*, J. Nauman, Metal Pass LLC, USA

Level 2 model improvement projects revealed various metallurgical is-sues that negatively affect the current Level 2 model. The considerable re-tained strains due to uncompleted recrystallization, and the metallurgi-cal phenomena during hold and two-phase region rolling, etc., causesignificant model errors which cannot be removed by adaptive learning.Wide application of metallurgical processes in today’s steel rolling callsfor a Level 2 model to fully consider metallurgical principles. The next-generation Level 2 model should include a hybrid system by combining afull-range of metallurgical models with intelligent learning such as neu-ral network, together with an expert system to guide the learning. Thenew model would also improve the pass schedule in controlled rollingprinciple and provide assistance for the Level 3 scheduling. The revealedmetallurgical issues, the general concepts of the next-generation Level 2system and the related metallurgical models, etc., will be introduced.

Fundamentals & Characterization: RecentAdvances in Structural Characterization ofMaterials

X-Ray and Neutron Diffraction: Developments andApplications IIIRoom: 309Session Chairs: Dean Haeffner, Argonne National Lab; ZhonghouCai, Argonne National Lab

8:00 AMUse of High-Energy X-rays for Phase and Strain Mapping (Invited)J. Almer*, D. Liu, Argonne National Laboratory, USA; S. Stock, NorthwesternUniversity, USA

Recent results at the Sector1-ID beamline utilizing high-energy x-rays for strain and phase mapping are presented. The combination of

an undulator source, brilliance preserving optics and focusing lensesprovides high-energy x-rays (E~80 keV) with transverse beamsizesdown to the micron-level, while a conical lens can be used to providelongitudinal resolution on the 100 micron-level for 3-d mapping. Inaddition to their high penetration power, a key feature of high-energyx-rays is their forward scattering geometry, which when combinedwith area detectors allows for efficient collection of scattering data,both in the small- and wide-angle regimes. Specific studies discussedwill include combined small- and wide-angle scattering measure-ments of strain partitioning in bone under in situ loading, and strainand phase mapping of solid-oxide fuel cells.

8:20 AMDetermination of grain scale deformation in a single phasetitanium alloy (Invited)M. P. Miller*, Cornell University, USA; U. Lienert, J. V. Bernier, ArgonneNational Laboratory, USA; M. Mills, M. Brandes, The Ohio StateUniversity, USA

Synchrotron x-ray experiments have changed the manner in whichwe characterize structural materials. Measurements of deformingpolycrystalline aggregates in-situ are now possible as are measure-ments of individual crystals within the aggregate. The talk describesrecent individual grain measurements made on the titanium alloy, Ti-7Al at beamline 1-IDC at the Advance Photon Source at the ArgonneNational Laboratory. Using in-situ loading and area detectors, deter-mination of the full stress tensor at various macroscopic loads forseveral grains within the aggregate were made. We also made detailedmeasurements of individual reflections to understand deformation-induced grain subdivision and strain partitioning.

8:40 AMHigh-energy x-ray diffraction at ID15 of the EuropeanSynchrotron Radiation Facility : Advances in materialscharacterization techniques (Invited)J. Daniels*, V. Honkimaki, European Synchrotron Radiation Facility, France

High-energy x-rays in the range of 50-150keV offer a unique andpowerful tool for materials characterization using diffraction tech-niques. Their high-penetration depth allows true bulk characteriza-tion, while low scattering angles makes possible many in-situ studieswhich are not achievable using other scattering probes. This presenta-tion aims to highlight recent advances in this area, in particular newdevelopments at beamline ID15 of the European Synchrotron Radia-tion Facility (ESRF). Several examples will be shown from a range ofexperimental setups to emphasize the ability for in-situ, and time-re-solved studies.

9:00 AMIn Situ Synchrotron X-Ray Studies of ZrO2 – In2O3Heterostructures (Invited)D. D. Fong*, J. A. Eastman, P. H. Fuoss, P. M. Baldo, T. T. Fister, M. J.Highland, H. Iddir, P. Zapol, Argonne National Laboratory, USA

Heterostructures comprised of fluorite-structured oxides with goodionic conductivity and oxides with high electronic conductivity havegreat potential for producing materials with novel mixed conductionproperties. Such behavior is of interest for a wide range of applica-tions, including solid oxide fuel cells. Here we describe the synthesis,structural characterization, and conduction behavior of ZrO2 (andY2O3-stabilized ZrO2 (YSZ))/In2O3 heterostructures produced byRF magnetron sputter deposition. Using synchrotron x-ray scatteringand high-resolution transmission electron microscopy, we find thatco-deposition of YSZ and In2O3 onto YSZ (001) substrates results inthe formation of a single-crystal nanocomposite with epitaxial In2O3nanopillars/nanolamellae dispersed in a YSZ matrix. The embeddednanopillars/nanolamellae are coherently strained with the matrix inall three-dimensions. We compare the oxygen partial pressure- andtemperature-dependent in-plane and out-of-plane electrical proper-ties of these nanocomposites with those of ZrO2(YSZ)/In2O3 multi-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 114

Tues

day

AM

www.matscitech.org 115

layers using an environmental four-point probe station. This allowsinvestigations into the effects of nanostructure morphology, interfa-cial strains, and different phase mixtures on ionic and electronictransport. We also carry out first-principles calculations of the sameheterostructures to provide insight into the effects of interfacial prox-imity on optical and conduction properties. The role of surface polar-ity on equilibrium structures, interfacial segregation behavior, andtransport will be discussed. This work is supported by the U.S. De-partment of Energy under Contract No. DE-AC02-06CH11357.

9:20 AMDetermining lattice site occupancies and chemical segregation in anickel based super alloy using x-ray and neutron diffractionJ. Tiley*, USAF, USA; R. Banerjee, University of North Texas, USA; G. B.Viswanathan, R. Srinivasan, H. L. Fraser, The Ohio State University, USA

A nickel based super alloy was subjected to different heat treatmentcooling rates and aging times to produce varying gamma prime sizedistributions and volume fractions. The materials were evaluatedusing synchrotron and neutron diffraction techniques with Rietveldreconstruction to provide volume fractions, chemistries, lattice pa-rameters and site occupancies for alloying elements within thegamma and gamma prime structures. Results are compared with re-sults for other nickel alloys and used to validate models for chemicalsegregation and lattice expansion as a function of temperature andaging time. Model parameters were coompared with TEM, SEM andlocal electrode atom probe results for volume fractions, lattice pa-rameters, and chemical composition.

Spectroscopic Techniques: Developments andApplicationsRoom: 309Session Chair: Juan Nino, University of Florida

10:00 AMMicrowave, THz and FTIR characterization of ultrathinferroelectric and magnetoelectric films (Invited)S. Kamba*, D. Nuzhnyy, V. Goian, V. Bovtun, M. Kempa, P. Kuzel, C. Kadlec,Institute of Physics, Czech Republic; C. M. Brooks, J. H. Lee, D. G. Schlom,Pennsylvania State University, USA; J. Schubert, Forschungszentrum Julich,Germany; M. Orlita, Grenoble High Magnetic Field Laboratory, France

Both compressive and tensile strains in epitaxial perovskite thinfilms permit the induction of a ferroelectric phase in quantum para-electric thin films. Interdigitated electrodes are used for dielectricmeasurements of such thin films, however this method is rather dif-ficult and frequently inaccurate. We investigated the complex per-mittivity of SrTiO3 and EuTiO3 strained thin (15-40 nm) films con-tactless using the microwave (MW) split-post dielectric resonatorand by means of time-domain THz transmission and infrared re-flectance spectroscopy. The phase transitions are manifested by max-imum in the MW permittivity as well as by minimum soft-mode fre-quency near Tc. In SrTiO3 and EuTiO3 films deposited on (110)DyScO3 substrates we observed the ferroelectric transition nearroom temperature. For the first time, the tuning of ferroelectric softmode frequency with the magnetic field was revealed inEuTiO3/LSAT, which is in origin of earlier reported magnetoelectriceffect in EuTiO3.

10:20 AMUltrafast Dynamics of Carrier Localization (Invited)S. L. Dexheimer*, Washington State University, USA

The localization of electronic excitations is an important funda-mental process and has a dramatic impact on the optical and trans-port properties of materials. We present femtosecond time-re-solved studies of the dynamics of carrier localization processesusing the techniques of time-resolved terahertz spectroscopy, inwhich short pulses of far-infrared light are used to monitor the

photoinduced carrier response, and vibrationally impulsive excita-tion, in which optical pulses short compared to the periods of rele-vant vibrational modes are used to time-resolve the coupled elec-tronic and lattice dynamics associated with photoinducedstructural changes. Intrinsic carrier localization processes, in whichself-trapped excitons and polarons form as a result of the electron-lattice interaction, are investigated using structurally tunablemodel quasi-one-dimensional materials. Studies of photoinducedcarrier dynamics in amorphous semiconductors reveal disorder-in-duced carrier localization associated with trapping in band tailstates.

10:40 AMAtomic-resolution studies of Ca3Co4O9 using in-situ scanningtransmission electron microscopyG. Yang*, Y. Zhao, R. F. Klie, University of Illinois at Chicago, USA

Ca3Co4O9 (CCO) has been of great interest as a potential thermo-electric material, due to its high thermal power and low thermal con-ductivity. Extensive studies have been performed to analyze the struc-ture and properties of this incommensurate layered material.However, the atomic and electronic structures of Co in different lay-ers are not well understood. By combining atomic-resolution scan-ning transmission electron microscopy with electron energy-lossspectroscopy (EELS), we study the chemical composition and Co ox-idation states in different layers. We find that significant charge trans-fer from CoO2 to Ca2CoO3 occurs. The proposed spin-state transi-tion at 420K on the local atomic and electronic structure will bestudied by in-situ heating experiments. Thus, we will demonstratethat atomic-resolution Z-contrast imaging with EELS and in-situ ex-periments can be utilized to understand the effects of interfacialcharge transfer and spin-state transitions in complex oxide materials.

11:00 AMDevelopment and Applications of in situ Electrochemical-NMRSpectroscopyX. Zhang*, J. W. Zwanziger, Dalhousie University, Canada

Electrochemical-NMR (ECNMR) spectroscopy is a combinedmethod in which the electrochemical reaction occurs directly in ahigh-resolution NMR probe, permitting acquisition of high resolu-tion NMR spectra under electrochemical potential control. We haveaccomplished, for the first time, simultaneous in situ ECNMR spectrain a 5 mm high resolution NMR probe. This was achieved with an or-dinary commercial 250 MHz FT NMR spectrometer in non-spinningmode. In this talk, the design and development of a three electrode, 5mm o.d. NMR cell will be presented, followed by some interesting ap-plications (e.g., studies of potential controlled conformational mo-lecular switches and battery-used materials) related to material struc-ture and behavior characterization. All NMR spectra were collectedsimultaneously during the course of electrochemical reaction. Bothaqueous and non-aqueous media applications will be demonstratedusing this homemade ECNMR cell.

11:20 AMScratch-Induced Microplasticity, Microcracking and ResidualStresses in ZrB2-SiCG. Subhash*, D. Ghosh, University of Florida, USA; N. Orlovskaya, Universityof Central Florida, USA

A ZrB2-SiC composite was subjected to scratch loads using aBerkovich nanoindenter. Microstructural analysis revealed the pres-ence of numerous slip bands and microcracks with in the scratchgrooves. The observed features were rationalized based on the elasticstress field due to the combined Boussinesq- and Cerruti- field solu-tions. The maximum shear stress ahead of the scratch tool causes sliplines and the maximum principal tensile stress in the wake of the toolcauses microcracks. A mechanics-based analytical framework for de-termination of scratch-induced residual stress within SiC particleswas developed using Raman spectra collected from SiC particles. It is

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 115

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania116

determined that in the as-processed composite, thermal expansioncoefficient mismatch between ZrB2 and SiC induces compressiveresidual stress within the SiC particles and a tensile tangential stressalong the interface. With increasing scratch loads, the residual stresswithin the SiC particles becomes tensile.

Iron & Steel: International Symposium onMaterials Engineering for StructuralApplications

Thermo-Mechanical Control ProcessingRoom: 328Session Chairs: Matthew Merwin, U.S. Steel Research & TechnologyCenter; C. Issac Garcia, University of Pittsburgh

8:00 AMCost Effective Microalloy Structural Steel Balance of ProcessMetallurgy and Materials EngineeringS. G. Jansto*, CBMM-Reference Metals Company, USA

Strategies to meet the current challenge of cost effectively and eco-nomically melting and hot rolling structural steels to meet the de-manding material and civil engineering needs of the end user are pre-sented. The increasing cost of raw materials, energy, yield andproduction cost is a key factor in designing structural steelchemistries that cost effectively satsify both the steel producer and theend user demands. Process metallurgy equipment and operatingpractice constraints often hinder the success in consistently produc-ing quality microalloy plate steels that will meet these stringent civilengineering specifications for toughness and strength. Some struc-tural steel application examples are made to illustrate a best fit opera-tional methodology to match a given rolling mill’s capability with theend user’s needs.

8:20 AMMicrostructural and Processing Factors Affecting the Formationof Pro-eutectoid Cementite in SAE 1092 Wire Rod SteelF. Borchardt, ArcelorMittal Monlevade, Brazil; C. Garcia*, M. Hua, A. J.DeArdo, University of Pittsburgh, USA

In order to produce lighter wires with higher strength and ductility,conventional high strength-high carbon steels such as SAE 1092 arebeing systematically investigated. This type of steel is capable ofachieving high strength values due to its high carbon content, how-ever, a major shortcoming of this steel is its relative lack of ade-quate ductility for a given intended application. In this work, thelack of ductility of this steel has been shown to be related to the for-mation of the brittle pro-eutectoid cementite along the prioraustenite grain boundaries. This paper examines the effect of themicrostructural condition of the austenite prior to transformationand the subsequent formation of pro-eutectoid cementite. In addi-tion, this paper will also comment on the thermal path conditionsneeded to reduce or eliminate the formation of pro-eutectoid ce-mentite, resulting in an increase in ductility without sacrificingstrength.

8:40 AMDevelopment of High Performance Steels for Bridge Applicationsat IPSCOD. Bai, T. Nelson, R. Bodnar, IPSCO Inc., USA; S. Scumpu*, IPSCO Inc.,Canada; M. Cooke, IPSCO Inc., USA

High Performance Steels (HPS) offer higher strength, improvedweldability, increased toughness, and enhanced atmospheric corro-sion resistance,and have been increasingly employed in U.S. bridgegirder applications. To support the rapid growth in high perform-ance steel use, IPSCO initiated, in 2003, a product developmentprogram for HPS-50W and HPS-70W steel plates. Various thermo-

mechanical controlled processing (TMCP) routes for high per-formance steel plate production were investigated, culminating inthe successful development of practices to produce HPS plates inthicknesses up to 2 inches. Crucial to the success of this programwas the evaluation of the effects of aging on the flow curve behav-ior of controlled-rolled + accelerated cooled plates. This paperprovides an overview of IPSCO’s experiences with the develop-ment of production practices for TMCP HPS-50W and HPS-70Wplates.

9:00 AMEffect of Alloying Additions in the Final Microstructure of Nb-MoSteels Processed by Thin Slab Direct Rolling TechnologiesJ. Ganzarain, D. Jorge-Badiola, P. Uranga*, J. M. Rodriguez-Ibabe, CEIT andTECNUN (University of Navarra), Spain

The effect of niobium and molybdenum on the austenite evolutionand transformation has been studied simulating thin slab directrolling conditions. Several laboratory thermomechanical scheduleshave been designed. Depending on the alloying content, deforma-tion temperature and the cooling rate, a broad spectrum of mi-crostructures have been created; varying from homogeneous ferriticor acicular structures to heterogeneous microstructures originatedby a lack of austenite refinement prior to transformation. EBSDanalysis have been carried out in order to measure ferritic unit sizes.Drag mechanisms are clearly affected by Mo alloying, inferring a re-tardation in coarse grain recrystallization and an increase of re-tained strain. Additionally, the hardenability is enhanced, favoringthe formation of acicular structures rather than equiaxed ferriticgrains.

9:20 AMTransformation Characteristics of M-A Constituents in Nb-TiMicroalloyed, Low-Mn Steel and Their Effect on MechanicalPropertiesQ. Sha, Anshan Iron and steel Group, China; C. Garcia, M. Hua*, A. J.DeArdo, University of Pittsburgh, USA

Most modern X80 pipeline steels achieve their high strength withhigh Mn levels and a low transformation temperature. The high Mnalso leads to segregation in the slab and to a heterogeneous mi-crostructure in the hot band. The heterogeneous microstructureand Martensite/Austenite (M-A) constituents may result in a poortoughness at low temperature. This work is to study the transfor-mation of M-A constituents in three Nb-added, low-Mn steels,after simulated HSM process and continuous cooling. M-A con-stituents were found throughout the multiphasemicrostructure,usually inside the ferrite grains, along grain bound-aries or mixed with acicular ferrite or pearlite. Its volume fractionincreased with Mn content and/or decreasing the coiling tempera-ture. The effect of M-A on the low temperature toughness behaviorof the steels will also be discussed.

10:00 AMQuantitative evaluation of hydrogen embrittlement on fatiguetoughness of galvanized high strength steelE. J. Petit*, Université de Metz, France; M. Gilles, Umicore, Belgium; S. Aden-Ali, A. Chamat, J. Gilgert, Z. Azari, University of Metz, France

Degradation of fatigue endurance after galvanization of a high highsilicon TRIP steel has been reported previously. The hypothesis of hy-drogen embrittlement is presently evaluated quantitatively. Referencesamples were prepared following the standard industrial procedure.Fatigue lifetime of samples - modified by decomposing the flux in amelted salt bath, and - electrochemically saturated with hydrogen arecompared to reference samples. This procedure enables to separateeffects due to : - the thermally induced bulk transformations into thesteel substrate, - modifications of the surface layer after chemical

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 116

Tues

day

AM

www.matscitech.org 117

etching and fluxing, and - reduction of fatigue toughness related tohydrogen diffusion. Hydrogen embrittlement is found to contributesignificantly to the reduction of the lifetime of galvanized highstrength steels.

10:20 AMRole of Vacancy and Dislocation on Hydrogen DegradationH. Shoda*, K. Takai, H. Suzuki, Y. Hagihara, Sophia University, Japan

Hydrogen absorbed during corrosion or under high-pressure hy-drogen causes the degradation for mechanical properties. Theprincipal role of vacancy and dislocation causing the degradationwas investigated using Inconel 625 as an face-centered-cubic (fcc)metal and pure iron as a body-centered-cubic (bcc) metal. The hy-drogen and strain induce the formation of lattice defects in bothmetals. The principal factor causing hydrogen degradation is theformation of vacancies and vacancy clusters induced by hydrogenand strain, since the specimens maintaining at the temperature of473 K which annihilates vacancies and vacancy clusters recoverductility completely. Hydrogen in both metals is transferred duringplastic deformation, that is, dragging motion of dislocation. Fromthese results, the vacancies and vacancy clusters affects the degra-dation directly, and dislocations with hydrogen induce the vacancyformation.

10:40 AMCharacterization of TRIP - Assisted Steel and Applied MethodsJ. Kliber*, O. Zacek, S. Nemecek, B. Masek, VSB-Technical University, CzechRepublic

The TRIP phenomenon is based on making substantial amount ofretained austenite stable down to low temperatures by means ofthermomechanical treatment and, subsequently, transforming theretained austenite into strain-induced martensite due to plasticdeformation. This paper is focused on simulation of thermome-chanical treatment using several different techniques, includinglaboratory methods (SMITWELD TTU 2002 and GLEEBLE3800). Thermomechanical rolling on the TANDEM rolling millwas performed as well. Conventional metallographic techniqueswere used for this purpose: light microscopy, electron microscopyusing SEM, image analysis software and X-ray diffraction for eval-uation of volume fractions of phases. However, some less com-mon metallographic techniques were applied as well: EBSD - Elec-tron Back Scattered Diffraction, neutron diffraction and laserconfocal microscopy.

11:00 AMMicrostructural Influence on Hydrogen Delayed FractureResistance of High Strength SteelsJ. Kim*, K. So, Pohang University of Science and Technology, South Korea; Y.Lee, POSCO, South Korea; C. Lee, Pohang University of Science andTechnology, South Korea

This study aims to investigate the effect of microstructure on the hy-drogen delayed fracture resistance of high strength steels. For thispurpose, two different microstructures revealing identical tensilestrength level (approximately 1600 MPa) were used; one is a marten-sitic microstructure and the other is a pearlitic microstructure. Hy-drogen delayed fracture resistance of each microstructure was evalu-ated by considering both critical hydrogen content (Hc) and thehydrogen content absorbed from the environment (He). The resultsshowed that pearlitic microstructure was more resistant to hydrogendelayed fracture than martensitic microstructure. The fracture sur-face morphology was a mixed mode (intergranular and transgranu-lar) in the martensitic steel, while that of a pearlitic steel was a ductilemode. The roles of microstructural parameters on the delayed frac-ture were discussed in relation to the activation energy of hydrogenfor detrapping.

Iron & Steel: Recent Developments in SteelProcessing

ProcessingRoom: 329Session Chair: Maciej Pietrzyk, Akademia Gorniczo Hutnicza

8:00 AMThe Effect of Cool Deformation Processing on the Structure andProperties of a Pipeline SteelA. Elwazri*, J. Calvo, S. Yue, McGill University, Canada

Abstract Cool deformation processing to achieve refinement mi-crostructures and better mechanical properties is an important di-rection for the future application of low C microalloyed steels. In thisstudy, torsion specimens of pipeline steel were subjected to a simula-tion of an industrial rolling schedule. After applying the industrialrolling schedule, some specimens were aged at 400, 500 and 600 Cfor 30 minutes followed by air-cooling. Another series of tests in-cluded the application of a ‘cool deformation’ at 400, 500, 600°Cprior to aging. The results revealed that the Nb(C,N) precipitates in-crease with decreasing temperature and increasing cool deformationstrain.

8:20 AMAnalysis of copper precipitates in ferrite matrix in pipeline steelsA. Fatehi*, A. Elwazri, J. Calvo, S. Yue, McGill University, Canada

According to previous studies, even low amounts of copper (e.g.~0.4wt.%) can contribute to strengthening of the steel. The reason,which can be solid solution and/or precipitation strengthening, is yetto be confirmed. In this work, steels containing Mo and different Nband Cu levels were subjected to small amounts of plastic deformationin the ferrite region (400 and 500°C) followed by air-cooling. Differ-ent methods ranging from transmission electron microscopy (TEM)to nano-indentation were used in order to characterize the precipi-tates and different phases existing in the microstructures. Resultswere confirmed by theoretical models related to kinetics of precipita-tion in ferrite.

8:40 AMFerrite Substructure as an Elevated Temperature StrengtheningMechanism for Fire-Resistant (FR) Structural SteelR. Regier*, J. G. Speer, D. K. Matlock, Colorado School of Mines, USA; S.Jansto, Reference Metals Company, USA

Use of high strength low alloy (HSLA) steel for structural applica-tions may reduce the need for costly fire resistant coatings by improv-ing the resistance of steel to softening at elevated temperatures. Varia-tions in the thermomechanical processing schedules of niobiumcontaining fire-resistant steel were used to investigate the presence offerrite substructure and its effects on elevated temperature strength,and results have been reported in a prior publication. In the presentcontribution, electron backscatter diffraction (EBSD) was used to ex-amine in further detail the effects of finish rolling temperature on theformation of low angle boundaries (LAB) associated with warmrolling and allow further interpretation of elevated temperature per-formance. Additional elevated temperature testing was performed toexamine test conditions that could be incorporated into new industrystandards.

9:00 AMAlloy and Process Development for Thin-wall HoneycombStructureT. H. Sanders*, J. K. Cochran, Georgia Institute of Technology, USA

Complex metal honeycomb structures are being fabricated using apowder oxide extrusion process at room temperature. The extrudedoxide pastes are subsequently reduced in hydrogen to a metallic body

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 117

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania118

and solid-state sintered to high wall density. The alloys can then beheat treated as any alloy fabricated using traditional processingroutes. Numerous alloy systems have been investigated including:copper, Fe-Cr, Fe-Ni-Cr, and maraging steels. A major break-throughin this work came about as a consequence of adding specific amountsof carbon by controlling the CO/CO2 equilibrium after reduction inhydrogen. Low cost steels including plain carbon steels and higherstrength alloys such as 4140 and can now be produced in the form ofa low density thin wall honeycomb structures. As in traditional pow-der processing methods, porosity, homogeneity, shrinkage, and mi-crostructure must be understood with respect to the various process-ing steps.

9:20 AMAustenite Formation in Plain Low Carbon SteelsH. Azizi-Alizamini*, M. Militzer, W. J. Poole, The University of BritishColumbia, Canada

Austenite formation in steels is a key step in the production of inter-critically annealed advanced high strength steels. For example, dualphase steels can be produced via intercritical annealing of cold rolledferrite/pearlite microstructures. Therefore, better understanding ofthe effect of crucial processing parameters like heating rate and coldreduction on austenite formation is essential for further improve-ments. In this study, a systematic experimental work has been con-ducted on the effect of these parameters on austenite formation inplain low carbon steels using dilatometry and microscopic tech-niques. Based on dilatometry results austenite formation can be di-vided into different stages consisting of pearlite dissolution, austenitelattice expansion and ferrite to austenite transformation. There is asignificant effect of the examined parameters on the resulting mi-crostructural evolution and the consequences and opportunities re-lated to these effects will be discussed.

10:00 AMDesign of Rolling Schedules Using an Optimization ToolB. Peña, M. Arribas, A. Carrillo, J. I. Barbero*, LABEIN, Spain; J. Calvo, S. Yue,McGill University, Canada

Most hot rolling models predict microstructures and properties froma given rolling schedule. In order to design a rolling schedule toachieve a specified microstructure and property, changes in therolling schedule parameters have to be suggested, and the model isthen run with the new schedule. In this work, a predictive softwarewhich works together with an optimization module is presented. Thistool systematically considers all the rolling parameters, and then gen-erates ‘optimized’ rolling schedules which lead to the specified me-chanical properties in terms of grain size. The thermal evolutionalong the thickness of the slab and its influence in the microstructurehas also been included. It can handle both C and microalloyed steels.For the validation, the program was requested to generate scheduleswhich would lead to certain predefined austenite grain sizes. Theschedules were then run by means of hot torsion testing, and themeasured austenite grain sizes showed that the optimization tool wasworking properly.

10:20 AMDevelopment of the Online Stelmor Quality Prediction SystemW. Yu*, University of Science and Technology Beijing, China; S. Chen, Y.Kuang, K. Cao, Jiangsu Shagang Group Co., Ltd., China

An online Stelmor control cooling system (SCCS) has been developedsuccessfully for the Stelmor production line, which can communicatewith the material flow management system and PLC automaticallythrough local network. This online model adopts Implicit Finite Dif-ference Time Domain (FDTD) method to calculate temperature evo-lution during the production process and predicts final properties. Assteels’ CCT figure can be coupled in the model, it can predict the la-tent heat rise and range of phase transformation for various steels,which can provide direct guidance for new steel development and op-

timization of present Stelmor cooling process. This unique onlinesystem has been installed in three Stelmor production lines in chinaat present with good results.

10:40 AMEffect of Thermomechanical Processing Parameters on theMechanical Properties of API X80 SteelsK. Al Hajeri*, W. Al Shalfan, SABIC Technology Center, Saudi Arabia; S. AlShammary, Saudi Iron and Steel Company (HADEED), Saudi Arabia

Mechanical properties of API steels are function of their final mi-crostructure, while the microstructure itself is a function of thechemical composition and processing parameters. The mechanicalproperties of a single chemistry can alter remarkable with changingthe thermomechanical processing (TMP) parameters while targetingthe same thickness. The effect of different hot strip mill (HSM) pro-cessing parameters on the microstructure and mechanical propertiesof API X80 steel was studied using two different microalloyed steels.Under similar deformation conditions, the effect of finishing rollingtemperature (FRT) and coiling temperature (CT) on the final prod-uct were identified. Control FRT above the transformation tempera-ture (Ar3) and maintain low CT allows forming the desired ferrite-bainite microstructure to achieve the required properties.

11:00 AMPower for Slitting of Metal StripL. Yan*, B. Snider, SMS Demag Ltd., Canada

Mathematical investigation on power required for slitting of metalstrips using both force analysis approach and energy method has ledto an identical theoretical solution. The derived power is a product ofstrip shear strength, square of strip thickness and speed of disc knifeedge. The power value from present solution is much lower thanthose from published equations and charts. Solutions for slittingtorque and force are also derived. Practical application is presented.

11:20 AMCold Forming Process for Net Shaped Automotive Ring GearsR. Whitbeck*, T. Tonello, Ford Motor Company, USA

Helical parallel axis ring gears for automotive applications are typi-cally produced by broaching process which is capital intensive, slowand requires a large inventory of broach tooling. A single step extru-sion process has been developed at Ford Motor Company to reducecost, capital investment and improve plant floor environment. Extru-sion of gear teeth is consistent and doesn’t require liquid lubricationor special fluids. Production rates have been shown to be muchhigher than for broaching. Five technology patents exist and there isconsiderable “know how” in tooling design, metallurgical processing,coatings, tooling and press operation. The process is not in produc-tion, but gear geometry has met design specifications and severalproduct test sequences have been completed. High replication poten-tial exists in the automotive sector as every automatic transmissionuses ring gears.

Iron & Steel: Steel Product Metallurgy andApplications

Microstructure - Property Correlations IRoom: 330Session Chair: James Warren, ArcelorMittal USA

8:00 AMEffect of Microscopic Deformation Characteristics of MnSInclusions in Free Cutting Steels on Development of Built-up EdgeN. Matsui*, Sumitomo Metal Industries, Ltd, Japan; J. Fujiwara, OsakaUniversity, Japan

Low carbon leaded free cutting steels are widely used in manufactur-ing industry. However, the use of lead is not favorable from the envi-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 118

Tues

day

AM

www.matscitech.org 119

ronmental point of view. Therefore, it is important to secure goodmachinability by the use of MnS inclusions instead of the lead. In thisstudy, the deformation behavior of the inclusions in machiningprocess was microscopically investigated using a leaded steel and twonon-leaded steels which contained different type of MnS inclusions.In the leaded steel, micro-cracks grew from the deformed globularMnS at the vicinity of built-up edge(BUE), which seemed to con-tribute to reduce BUE size. In the non-leaded steels, the size of BUEgenerated from the steel containing the globular MnS was small sim-ilar to the leaded steel, but one from the steel containing the slenderMnS developed bigger. These behaviors would be explained by thedifferent deformation characteristics of distinct type of MnS.

8:20 AMEffect of MnS Distribution on Machinability in Low C Lead-freeFree-cutting SteelM. Hashimura*, K. Miyanishi, A. Mizuno, NIPPON STEEL CORPORA-TION, Japan

Conventionally, low carbon free-cutting steels are added lead (Pb) inorder to cut the complicated and precise configurations of variousparts. However, lead is listed in EU Directives as a harmful elementfor environments. In these parts, the first priority in developing lead-free free-cutting steel is not only to facilitate high-efficiency cuttingbut also to provide, without using lead, an extremely smooth finishedsurface after machining. Usually, to achieve long tool life in steel cut-ting, sulfur is added and it forms MnS inclusions in the steel. How-ever, the shape and distribution of MnS have great effect on the sur-face roughness of machined surfaces. Therefore, in this paper, theeffect of MnS distribution is studied. As a result, it is clarified that thedeveloped steel with high S content and homogeneous distribution offine MnS grains has better machinability, especially on the surfaceroughness, than that of the conventional leaded steel, SAE12L14.

8:40 AMDevelopment of MnS and IGF Control in Microalloyed SteelsY. Jiang*, BaoShan Iron and Steel Co., Ltd. , China

Adding sulfur element in microalloyed steels can improve steels’machinability and ameliorate the shape and distribution of ferrite,accordingly, refining the microstructure. The development of MnSand intragranular ferrite (refered as IGF) control in ferrite-pearlitemicroalloyed steels are reviewed in this paper. The production of fer-rite-pearlite microalloyed steels for hot forging has been developedcontinually in Baosteel special steel since 1987. Most of steels wereprepared by the process : EF-LF-VD- Ingot Casting - Hot rolling. Fer-rites are usually precipitated along coarse grain boundary (refered asGF) and the length of MnS is normally bigger than 50μm, and itslength-width ratio is bigger than 50 in the general steels. While ferriteis precipitated around the MnS and form IGF and the size of MnS hasbeen controlled, and its length is reduced more than 25 times, its as-pect ratio is reduced several hundred times than that in our new-opened steel. The refined and dispersive MnS not only can improvethe directivity of impact toughness of the steels, but impede the graingrowth under high temperature.

9:00 AMThe Effect of Inclusion Type on the Toughness of 4340 SteelP. Choudhary*, W. Garrison, Carnegie Mellon University, USA

HY180 and AF1410 have much higher toughness if sulfur is getteredas either large, widely spaced particles of lanthanum oxysulfide or assmall, closely spaced particles of titanium carbosulfide instead ofsmall, closely spaced particles of MnS or CrS. Toughness increases bygettering sulfur as titanium carbosulfide as it is much more resistantto void nucleation than MnS or CrS. The toughness of three heats of4340 are compared. In one heat the sulfur was gettered as MnS. In thesecond the sulfur was gettered as lanthanum oxysulfide. In the thirdsulfur was gettered as titanium carbosulfide. All three heats had ayield strength of about 1430 MPa. The fracture toughness was 87

MPa√m, 99 MPa√m and 108 MPa√m for the MnS heat, the lan-thanum modified heat and the titanium modified heat, respectively.These results will be discussed in terms of inclusion volume fractionsand spacings and void nucleation resistance.

9:20 AMThe Effects of Silicon and Rare Earth additions on the Strengthand Toughness of High Nickel Medium Carbon Low Alloy SteelsP. Choudhary*, W. Garrison, Carnegie Mellon University, USA

Some time ago it was shown a steel whose composition (in wt. %) was0.34C/3Ni/2Si/1Cr/0.5Mn had very high toughness. KIC was 115MPa√m and the Charpy energy was 65 J at a yield strength of 1682MPa. The high toughness was ascribed to the large spacing of the MnSinclusions. Initial heats to replicate these properties were successful,but later heats were not. The objectives of this work were to determineif the toughness of the original steel could be achieved by using rareearth additions to achieve widely spaced inclusions and to assess theeffects of silicon on the formation of rare earth oxysulfides and theirvoid nucleation resistance. Four heats were evaluated. Two had a com-position of 0.37C/3Ni/1Cr. No additions were made to getter sulfur inone heat and CrS was anticipated. In the second sulfur was gettered byrare earths to form widely spaced inclusions. The other two heatswere identical to these except for the addition of 2 wt. % Si.

10:00 AMNew Heat Treatment for Heavy Maraging Steel ForgingsM. Chatterjee, S. Krishnan*, Mishra Dhatu Nigam Limited, India

18Ni1700 maraging steel rings used in satellite launch vehicles are re-quired to possess a combination of ultra high strength and fracturetoughness. Adequate thermo-mechanical treatments under controlledconditions is required to achieve these objectives. Improper working re-sults in coarse unrecrystillized structure, with Ti (C, N) precipitationalong grain boundaries. Conventional annealing treatment fails to rectifythe microstructure, resulting in unacceptable KIC levels in products. Amodified two stages annealing treatment [950 °C (WQ) + 820 °C (WQ)],prior to aging significantly refines the martensite substructure and en-sures a fine grained steel free from Ti (C,N) precipitate.This enhances theKIC & ductility by 30%, with KIC of 100 MPa√m at yield strength of 1800MPa consistently achieved. Fractographic investigation shows transitionin fracture mode from intergranular to quasi cleavage failure. Presentpaper highlights results obtained during the course of investigation.

10:20 AMNew Filler Wire for Welding 250 Grade Maraging SteelsM. Chatterjee*, S. Krishnan, Mishra Dhatu Nigam Limited, India

As a part of design considerations, maraging 250 welds in rocket boostercasings should have 90% weld efficiency with respect to strength as well astoughness. While using filler wires of base metal composition, 90% effi-ciency in KIC could not be achieved, due to formation of secondary cracksin the relatively soft reverted austenite pools, formed in the interdendriticregions of weldmelt. EPMA showed Mo & Ti segregation, leading toaustenite reversion during aging. Consequently, Mo & Ti was reduced inthe new filler wire, while levels of Co & Al was increased to ensure ade-quate strength of welds after aging. Welds with modified filler wires werefree from reverted austenite, with KICof 85 MPa√m at strength level of1600 MPa, which translates to over 90 % weld efficiency with respect tostrength as well as toughness. The paper discusses structure and proper-ties of maraging steel weldmelts vis- a –vis composition of filler wires.

10:40 AMFerrite Transformation and Carbide Precipitation in a HighMagnetic Field in an Fe-C-Mo AlloyZ. Zhou, T. Hou, J. Zhang, K. Wu*, Wuhan University of Science andTechnology, China

The alloy Fe-0.28C-3.0Mo (wt%) was austenitized at 915 °C for 10min in the tube furnace and swiftly moved into the lead bath forisothermal holding at 530 °C for different times without and with a

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 119

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania120

magnetic field of 12 Tesla. The characteristic popcorn-like mi-crostructure, i.e. degenerate ferrite, was observed in this alloy. Theprecipitation of carbide was found in the transformed microstruc-ture. Mo2C and (Fe,Mo)3C are precipitaed at early stage withoutmagnetic field whereas no Mo2C and (Fe,Mo)3C is precipitated atthis stage with magnetic field. (Fe,Mo)6C is just precipitated at laterstage of the transformation without magnetic field. (Fe,Mo)6C is pre-cipitated at early and later stages with magnetic field. The results mayindicate that the precipitation sequence is changed by extenal field,proably due to the lowering Gibbs free energy of the high magnetiza-tion phase.

Materials & Systems: Advances in Biomedicaland Biomimetic Materials

Metallic Implant MaterialsRoom: 333Session Chair: William Wagner, University of Pittsburgh

8:00 AMTitanium with Aligned, Elongated Pores for Bone Replacement(Invited)D. Dunand*, Northwestern University, USA

This talk reviews processes developed to date for creating titaniumwith aligned elongated pores mimicking bone structure. In particular,we discuss two recent developments in our laboratory to create suchbiomimetic structures. First, we describe directional freeze-casting fortitanium. An aqueous slurry of Ti powders is directionally solidified,resulting in a powder preform consisting of elongated, aligned den-drites of pure ice separated by interdendritic regions with high pow-der content. After freeze-drying to remove the ice dendrites and sin-tering to densify the powders, the resulting titanium foams exhibitsaligned pores replicating the ice dendrites. Structure (tomography)and mechanical properties of these foams are presented. Second, wedescribe a new process where steel wires are embedded within a Timatrix and removed electrochemically to produce pores with control-lable shapes, dimensions, orientation, connectivity and surface finish.

8:40 AMLaser Deposited Functionally Graded Orthopedic Implants(Invited) (Invited)R. Banerjee*, University of North Texas, USA; S. Nag, S. Rajagopalan, OhioState University, USA; T. W. Scharf, University of North Texas, USA; H. L.Fraser, Ohio State University, USA

In recent years beta-Ti alloys have been found to exhibit properties befit-ting specific biomedical applications such as the stem of a hip implant,such as superior biocompatibility, lower modulus and relatively higherstrength. However, their poor wear-resistance severely restricts their ap-plicability in femoral heads, often resulting in the use of ceramic heads.Near-net shape processing technologies, such as the laser engineered netshaping (LENS™) process, offer a viable processing route for fabricationof functionally-graded implants with site-specific properties. Beta-Ti al-loys and wear-resistant boride reinforced metal-matrix composites, pre-pared by LENS™ are discussed with respect to their microstructuralevolution, tensile, electrochemical and in-vitro properties. In addition,some initial studies on developing a hard and lubricious coating forfemoral heads by sputter depositing zinc oxide onto the wear-resistantboride reinforced metal-matrix composite will also be discussed.

9:00 AMCharacterization of the Au-Ti Interface in Brazed Feedthroughsfor Medical Device ApplicationsA. J. Thom*, M. Reiterer, J. Popp, J. Heffelfinger, P. Yurek, G. Munns, S.Knowles, Medtronic, Inc., USA

Gold is used to form a hermetic seal between an electrically insulatingceramic and a metallic ferrule for electrical feedthroughs in the med-

ical device industry. Titanium is a commonly used ferrule material,and therefore it is important to understand the microstructure of thephases that form in the Au-Ti binary system. This paper discusses themicrochemical and micromechanical properties of the Au-Ti inter-face as measured from multiple carefully prepared cross sections of aAu-Ti braze couple. Evolution of the Au-Ti interface with tempera-ture and time was studied in an in-situ x-ray diffraction heating stage.The interfacial chemistry was measured by electron probe micro-analysis (EPMA), while the mechanical properties were characterizedby nano-indentation measurements. Finite element modeling (FEM)was also used to estimate the effect of the interfacial phases formedon the mechanical response of a feedthrough component.

9:20 AMMicrostructure and Mechanical Behavior of Ti-6Al-4V forBiomedical Applications Produced by Rapid-Layer-BasedManufacturing (Invited)L. E. Murr*, University of Texas at El Paso , USA; S. A. Quinones, Universityof Texas at El Paso, USA; S. M. Gaytan, M. I. Lopez, A. Rodela, E. Y. Martinez,D. H. Hernandez, E. Martinez, University of Texas at El Paso , USA; F.Medina, R. B. Wicker, University of Texas at El Paso, USA

The microstructures and mechanical behavior of simple productgeometries produced by layered manufacturing using the electronbeam melting (EMB) process and the selective laser melting (SLM)process are compared with those characteristic of conventionalwrought and cast products of Ti-6Al-4V. Microstructures are charac-terized utilizing optical metallography (OM), scanning electron mi-croscopy (SEM) and transmission electron microscopy (TEM), andincluded α (hcp), β (bcc) and α’ (hcp) martensite phase regimeswhich give rise to hardness variations ranging from HRC 37 to 57 andtensile strengths ranging from 0.9 GPa to 1.45 GPa (900 MPa to 1450MPa). The advantages and disadvantages of layered manufacturingutilizing initial powders in custom building of biomedical compo-nents by EBM and SLM in contrast to conventional manufacturingfrom Ti-6Al-4V wrought bar stock are discussed.

10:00 AMLow Modulus Porous NiTi Shape Memory Alloy for Load BearingImplantsV. K. Balla*, S. Bose, A. Bandyopadhyay, Washington State University, USA

Porous NiTi alloy samples were fabricated with 12 to 36% porosityfrom equiatomic NiTi alloy powder using Laser Engineered NetShaping (LENS) in a <10 ppm oxygen environment. LENS processedporous NiTi samples showed high amount of cubic B2 phase com-pared to cast NiTi alloys. High cooling rates associated with laser pro-cessing increased the reverse transformation temperature due to ther-mally induced stresses and defects. Transformation temperatureswere found to be independent of pore volume, while high pore vol-ume in the samples decreased the maximum recoverable strain from6% to 4%. Porous NiTi samples with 12 to 36% porosity exhibitedlow Young’s modulus between 2 and 18 GPa as well as high compres-sive strength and recoverable strain. These porous samples are thuspromising biomaterials for hard tissue replacement applications. Ourtalk will focus on process-structure-property correlation of theseporous NiTi alloy samples for load bearing implants.

10:20 AMCharacterization of New Nickel-Titanium Wire for RotaryEndodontic InstrumentsW. Brantley*, W. Clark, The Ohio State University, USA; M. Iijima, HealthSciences University of Hokkaido, Japan; S. Alapati, Medical University ofSouth Carolina, USA; C. Buie, J. Liu, The Ohio State University, USA; B.Johnson, SportsWire LLC, USA

Rotary endodontic instruments are machined from superelastic (SE)NiTi wires. Because instruments occasionally fracture in root canals,there has been much effort to develop improved alloys. Instrumentshave been introduced (Dentsply) that are machined from a new wire

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 120

Tues

day

AM

www.matscitech.org 121

(M-Wire) prepared by proprietary processing. M-Wire has substan-tially better ratio of tensile strength to upper superelastic plateaustress than conventional SE wire. Instruments machined from M-Wire have superior fatigue behavior. M-Wire and a conventional SEwire were examined by optical microscopy, scanning transmissionelectron microscopy, x-ray diffraction, and differential scanningcalorimetry, to learn if differences in microstructures might accountfor differences in mechanical properties. Results show that conven-tional SE wire is austenitic, whereas M-Wire contains martensite,R–phase and austenite. M-Wire has coarser submicron grains, andslip bands and twinning absent in conventional SE wire providestrengthening.

10:40 AMMechanical properties of implant rods made of Ti-29Nb-13Ta-4.6Zr for spinal fixtureK. Narita*, M. Niinomi, M. Nakai, T. Akahori, Tohoku University, Japan; K.Oribe, T. Tamura, S. Kozuka, S. Sato, Showa Ika Kogyo Co., Ltd., Japan

Currently, most of the implant rods are made of Ti-6Al-4V ELI alloy(Ti64). However, some problems have been pointed out regarding theTi64 rod; it contains relatively high toxic element, vanadium, forhuman body, and exhibits higher elastic modulus than that of corticalbone. Ti-29Nb-13Ta-4.6Zr alloy (TNTZ) developed by authors ex-hibits good biocompatibility due to nontoxic-elements, and lowerelastic modulus than that of Ti64. Therefore, the mechanical proper-ties of TNTZ rods subjected to various heat treatments were investi-gated in this study. The tensile strength and elastic modulus of theTNTZ rod aged at 723K is increased while the elongation is decreasedin comparison with those of the solutionized TNTZ rod because ofthe α phase precipitation. The tensile strength and elastic modulus ofthe TNTZ rod aged at 673K is increased while the elongation is de-creased in comparison with those of the TNTZ rod aged at 723K be-cause of the ω precipitation in addition to the α phase precipitation.

11:00 AMIn Situ Synchrotron X-ray Diffraction Study of Ti-Nb-Sn Alloysduring Aging ProcessesG. T. Aleixo, A. Cremasco, E. S. Lopes, State University of Campinas, Brazil; C.R. Afonso, Brazilian Synchrotron Light Laboratory , Brazil; R. Caram*, StateUniversity of Campinas, Brazil

Materials that combines high mechanical strength, high corrosion re-sistance and good biocompatibility is of vital importance when bonerepairing is necessary. The aim of this work was to study aging ofwater quenched Ti-Nb-Sn alloys by means of X-ray diffraction(XRD) using synchrotron radiation. High resolution X-ray diffrac-tion patterns provided by synchrotron radiation led to the identifica-tion of metastable phases formed in β Ti alloys, such as nanometric ωphase. The larger photon flux of synchrotron light provided betterresolution and more defined peaks for phase identification. The re-sults obtained suggested that aged samples at 200oC showed no sig-nificant changes. However, it shows evidences of ω-phase precipita-tion combined with α” martensite. As the temperature was increased,it was noted that decomposition of orthorhombic α” phase takesplace, forming β, ω phases and finally, α phase. Probably, α-phase nu-cleation was facilitated due to the presence of ω-phase precipitates.

11:20 AMEffect of cold work on the behavior of NiTi shape memory alloyM. M. Farag, M. E. Mitwally*, American University in Cairo, Egypt

This study examines the effect of cold work on the behavior of NiTishape memory alloy. An annealed 50.7 at% Ni alloy was subjected tocold rolling with reductions of 20%, 30% and 40%. The effect ofcold rolling on the structure was followed using X-ray diffractionand SEM. The mechanical properties were measured using tensionand hardness tests. Superelasticity was measured from loading-un-loading curves of the nanoindenter. The results show that increasingcold rolling causes progressive increase in martensite phase. Increas-

ing cold rolling was also found to cause an increase in recoverablestrain, tensile strength and hardness but reduces ductility and shapememory recovery. Most of the properties tested (P) were found tovary with the amount of cold rolling (CR) according to a quadraticpolynomial relationship: P = a (CR)2 + b (CR) + c Where a, b, and care constants. The use of the above relationship in predicting the be-havior of the NiTi alloy under different cold rolling conditions isdiscussed.

11:40 AMThermoplastic Elastomer Synthesis and Processing for Soft TissueRepair and Augmentation (Invited)W. Wagner*, J. Guan, Y. Hong, K. Fujimoto, J. J. Stankus, University ofPittsburgh, USA

A family of biodegradable poly(ester urethane)ureas was developed forcardiovascular and other soft tissue applications where approximatingtissue mechanical properties is desirable. By altering polymer designand processing methods selected bioactivity as well as mechanical andstructural biomimicry could be introduced. To control degradation, asoft segment with central variable length polyethylene glycol flankedby variable length polycaprolactone was used. Enzymatic lability wasachieved by incorporating enzyme-specific peptide sequences into thebackbone during polymer chain extension. Structural and mechanicalanisotropy was achieved by electrospinning or thermally inducedphase separation with thermal gradients. Composites were made byblending with collagen or extracellular matrix digests. For controlledrelease, growth factors (e.g. bFGF, VEGF) could be blended into thepolymers. Electrostatic coprocessing of polymer and cells allowed for-mation of tissue constructs with microintegrated cells and fibers.

Materials & Systems: Advances inCharacterization and Modeling ofCementitious Materials

New Developments Regarding ExperimentalTechniques for Characterizing Cement-basedMaterials IIRoom: 331Session Chair: Florence Sanchez, Vanderbilt University

8:00 AMEarly Age Particle-Stimulated Hydration KineticsJ. J. Biernacki*, T. Xie, Tennessee Technological University, USA; W. Hansen,University of Michigan, USA

Fine inert particles or fillers have been reported to promote earlyage hydration of C3S (tricalcium silicate) and other clinker phases.This effect has been attributed to the presence of an extended inertsurface provided by the filler particles. Such has similarly been re-ported for pozzolans including blast furnace slag and fly ash. Thepresent list of lumped parameter kinetic models typically used formodeling hydration are not well suited for this problem, thoughmany have been applied to blended systems containing pozzolans. Anew, more distributed model, with explicit, surface assignable nucle-ation and growth parameters has been explored which may provideinsights into very early age events including multiple surface nucle-ation and inner and outer CSH (calcium silicate hydrate) productgrowth.

8:20 AMUltrasonic wave reflection of aqueous solutions with variousconcentrationsC. Chung*, J. S. Popovics, L. J. Struble, University of Illinois, USA

Ultrasonic wave reflection (UWR) is used to monitor setting andstrength development in cementitious mixtures. When measured

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 121

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania122

using P-waves, changes in solution composition are seen to alter theUWR results. Using high impact resistant polystyrene (HIPS) as abuffer material, the UWR values were measurably reduced whenthe concentration of chemical species in solution was increased.With a single solute species, reflection coefficient showed a linearrelationship with solution concentration. However, the relation be-tween concentration and reflection coefficient changed when thesolute species was changed. When reflection coefficient data arecompared to solution density instead of concentration, data re-duced toward a unified linear relationship for all solution speciestested.

8:40 AMApplication of semi-adiabatic calorimetry to characterizehydration of cement pasteC. Chung*, L. J. Struble, University of Illinois, USA

Calorimetry has been used in research laboratories to characterizehydration of cement paste. However, construction of isothermal oradiabatic calorimetry is difficult compared to construction of asemi-adiabatic calorimetry. Semi-adiabatic condition is also closerto the conditions in concrete structures, so this technique is pre-ferred by field engineers. The objective of this research is to developbasis for interpreting results from semi-adiabatic calorimetry. Inone experiment, calorimetry was correlated with hydration reac-tions measured using X-ray diffraction (XRD) and thermal analysis(TA). In another experiment, semi-adiabatic calorimetry andisothermal calorimetry results were compared for the same ce-ments. One must always be careful in comparing semi-adiabatic re-sults obtained using different instruments. There were clear differ-ences between isothermal and semi-adiabatic calorimetry results,but both results may be used to explore the reactions occurring ascement hydrates.

9:00 AMIdentifying Cement-Admixture Incompatibilities through theMeasurement of Cement Paste RheologyA. Mukhopadhyay*, S. Jang, Texas Transportation Institute, USA

Rheological parameters were determined by a modified DynamicShear Rheometer (DSR) using (i) different mixtures (both normaland incompatible) with different type and dosages of admixtures,different types and contents of SCMs (fly ash, slag), (ii) varying in-strumental settings - five different plate gaps, varying initial shearrate (iii) high shear mixture with different speed, (iv) differenttemperatures. The DSR test results were verified by another ad-vanced rheometer (AR 2000, TA) in order to validate the DSR rhe-ological results. The heat of hydration data from isothermalcalorimeter test and setting time results for the studied mixtureshave strongly supported the rheology based observations as sup-porting tools. Cement paste rheology measurement techniqueusing the modified DSR has a great potential to identify cement -admixture incompatibilities.

9:20 AMNew Insights into the Behavior of Air-Entrained ConcreteT. Ley*, Oklahoma State University, USA

The quality control of air-entrained concrete is widely regarded as thebiggest challenge facing the concrete industry. This presentation givesan overview of the fundamentals of air-entrained concrete, relevantliterature, and provides new insights obtained from recent research. Anovel experimental technique will be presented using optical mi-croscopy that provides new insights into the physical properties ofair-entrained bubbles in cement paste. These techniques allow the be-havior of the material to be captured in digital images. Movies show-ing some fundamental behavior of the air-voids in reaction to outsideinfluences will be presented. Finally, chemical analysis of the air void

shell is presented using quantitative x-ray diffraction (QXRD) as wellas some limited investigations using scanning electron microscopy.

Modified Fresh or Hardened Properties andNontraditional Applications of Cement-basedMaterials IRoom: 331Session Chair: Florence Sanchez, Vanderbilt University

10:00 AMNew Developments in Cement Nanoscience (Invited)L. Raki*, J. Beaudoin, R. Alizadeh, National Research Council Canada,Canada

The application of nanoscience principles and tools plays a centralrole in producing innovative cement-based materials for the 21stcentury. The engineering properties of concrete materials are closelyrelated to the behaviour and response to phenomena of their com-ponents at the micro and nano levels. Nanostructural alterations tothe main binding phase in Portland cement concrete, C-S-H, couldhave a major effect on concrete properties. The use of admixtures inmodern concretes, dictated by the production of special concretesfor particular applications, is a common practice. A better under-standing of the type of interactions between these admixtures andcement phases at the nano level could give new insights to concretematerials performance at the micro and macro levels. The presenta-tion will focus on recent research work in the field of cement-basednanohybrids and nanoparticles with an emphasis on their synthesisand characterisation.

10:20 AMEffects of Liquid Nitrogen Cooling on Fresh Properties of Cement-Based MaterialsM. Juenger*, The University of Texas at Austin, USA; J. Hema, HaagEngineering Co., USA

Liquid nitrogen (LN) is quite possibly the most effective method ofcooling fresh concrete, but it does not have a long or widespread his-tory of use. Accordingly, there are very few records of its effects onshort and long-term concrete properties. In this study, the effects ofLN-cooling on a variety of cement paste, mortar, and concrete prop-erties were investigated. This presentation reports on some of themost surprising and significant results. These include the effects onconcrete slump and setting time and cement paste hydration as meas-ured by isothermal calorimetry. Surprisingly, LN-cooled concrete be-haves similarly to hot concrete mixtures with respect to slump andheat development, but much more like cool mixtures with respect tosetting time. These results have implications on the use of LN-coolingin the field for standard cooling practices as well as for potential newpractices such as intentionally delayed cooling to extend setting time.

10:40 AMThe Effect of Heat Treatment on the Tensile Creep of Ultra-HighPerformance ConcreteV. Y. Garas*, K. E. Kurtis, L. F. Kahn, Georgia Institute of Technology, USA

The tensile creep behavior of ultra-high performance concrete(UHPC) (reactive powder concrete) is investigated through short andlong-term creep studies, as well as in situ characterization by x-raymicrotomography in order to assess the underlying mechanisms fortensile creep in UHPC. UHPC is a very high strength, very low per-meability cement-based material reinforced with short, randomly-dispersed steel fibers, and it has been suggested that prestressed con-crete bridge girders may be produced from this material without anytransverse, shear reinforcement. Before specifying this material forgirder construction, the tensile creep performance has to be charac-terized to ensure adequate performance. In this study, the effect ofheat treatment on the tensile creep of UHPC is investigated. Resultshave shown significant reductions in the tensile creep parameters

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 122

Tues

day

AM

www.matscitech.org 123

(creep coefficient and specific creep) upon an early heat treatmentregime prior to loading.

11:00 AMEffects of Calcium Sulfoaluminate-Belite Cement Composition onHydration and PropertiesI. A. Chen*, M. Juenger, University of Texas at Austin, USA

Calcium sulfoaluminate-belite (SAB) cement has been manufacturedin China for 30 years, and has shown excellent properties in com-pressive strength, dimensional stability, and durability. Because of thedifferent phase assemblage compared to portland cement, SAB ce-ment requires less lime and energy for its formation, which leads toreduction in carbon dioxide emissions. In this study, 7 SAB cementclinkers with different phase proportions were synthesized. Therange of phase compositions was chosen because it allows full evalu-ation of the phase compatibility of the SAB cement system and theinter-relationship between phase compositions and performance.The synthetic clinkers and the hydration products that develop overtime were analyzed using x-ray diffraction, scanning electron mi-croscopy, and differential scanning calorimetry with simultaneousthermogravimetric analysis. Performance of the synthetic cementswas characterized through isothermal calorimetry and compressivestrength.

11:20 AMHow and why do geopolymers form?J. L. Provis*, P. Duxson, J. van Deventer, University of Melbourne, Australia

Geopolymers are gaining increasing attention worldwide as amore sustainable alternative to Portland cement in the productionof concrete, with commercial production of geopolymer concretescommencing in 2008. Geopolymers are generally synthesized byreaction of an alkaline solution with a waste-derived aluminosili-cate solid to form a hardened gel binder, and there is a need to un-derstand this process to enable control of setting rates and thefinal geopolymer structure. Here, we will show the importance ofthe physicochemical nature of the solid precursor in controllingthe progress and products of geopolymerization. We will alsopresent new insight into reaction mechanisms and geopolymernano- to microstructure, gained by coupling computational andexperimental techniques. The relationship between precursorproperties, geopolymer structure and geopolymer performance(mechanical, thermal and chemical durability) will be elucidatedin detail, and areas requiring further attention by the researchcommunity highlighted.

11:40 AMEffect of binder proportion on compressive strength ofgeopolymer mortarG. Babu*, M. Santhanam, S. Munish, IIT Madras, India

Geopolymer is a new technology in the field of construction in-dustry. Materials rich in silicates and aluminates are activated bymeans of alkali activators. This paper reports the results of thecompressive strength of the Fly ash (Class F) based geopolymermortar prepared with different binder proportions and chemicalratios. The compressive strength obtained was in the range of 10 to60 MPa. It was inferred from the results, that the increase in the ac-tivator solution showed increase in compressive strength, this ismainly due to the increase in Na2O content in the mixture whichis mainly required for the polymerization reaction. From thisstudy it was also inferred that the H2O to Na2O ratio of the mix isan important factor that decides the strength, with an increase inthe ratio resulting in a decrease of strength. The Micro structuralcharacterization of the selected mortars was also looked intothrough scanning electron microscopy (SEM), and X – ray diffrac-tion techniques.

Materials & Systems: Amorphous Materials:Common Issues within Science andTechnology

Polymers and Related MaterialsRoom: 334Session Chair: Mario Affatigato, Coe College

8:00 AMMD Simulation of Highly Crosslinked DCPD Polymers: HeuristicCreation Paradigms and Mechanical PropertiesC. Shankar*, J. Kieffer, University of Michigan, USA

Poly dicyclopentadiene (pDCPD) is created by ring opening metathesispolymerization (ROMP) mediated by Ruthenium based Grubb’s cata-lysts, resulting in a wide variety of polymer architectures and ensuingmechanical properties. We generated pDCPD networks using a combi-nation of molecular dynamics (MD) and a heuristic bond exchangeprotocol, recreating the ROMP pathway. Mechanical properties of thenetworks were evaluated by subjecting them to uniaxial tension tests atvarious degrees of reaction. We show that rubber elasticity theories areinapplicable here because deformation of these highly crosslinked net-work polymers is no longer isenthalpic. We observe mechanical perco-lation at nc~1.4 in contrast to conventional rigidity percolation theo-ries of glasses where nc~2.4 and provide possible explanations for thisbehavior based on detailed characterization of the network topology.

8:20 AMPhysical Aging in Polymer Films subjected to Nonlinear Stress LevelsY. Guo*, R. Bradshaw, University of Louisville, USA

This paper focuses on physical aging of glassy polymers in their non-linear range. The nonlinearly tensile creep responses of PEEK and PPSfilms were investigated by a dynamic mechanical analyzer (DMA), attemperatures 15-35°C below the glass transition temperatures (Tg).To characterize the material behavior, several stress levels beyond thelinear region were applied at each aging temperature during creeptests. The sequenced creep tests were performed after quenching froma temperature 5°C above Tg to desired temperatures, the results wereanalyzed by MATHCAD and PHYAGE program. On the other hand,this article presents an approach to describe the experimental data ofnonlinear physical aging. This method is based on Schapery model, itincorporates aging shift factor into Prony series, in order to representthe creep compliance at various aging times and stresses. Predictionsof compliance using this approach are compared with the experimen-tal results. Good agreement shows the validation for this method.

8:40 AMLamination of Differentially Densified Glass-CeramicsJ. Dorsey*, I. E. Reimanis, Colorado School of Mines, USA; L. R. Pinckney,Corning Inc, USA

Glass ceramics with different thermally crystallizable core and skinlayers are laminated together to form a trilayer specimen with the ob-jective of understanding and controlling strengthening mechanismsin glass. By adjusting the glass composition and the total volumechange during crystallization in each layer, differential densificationbetween layers can lead to a variety of residual stress distributions.Two differential densification mechanisms are possible: 1) the skindensifies less than the core, OR 2) the skin expands greater than thecore. In the first case, the formation of high density crystals that oc-curs in the skin during crystallization is less than that which occurs inthe core. In the second case, the skin material is selected so that it ex-pands due to the formation of low density crystal phases during heattreatment. The core would comprise a material that has negligiblevolume or density change during the crystallization process. In bothcases, a compressive layer forms on the surface of the article.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 123

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania124

9:00 AMEffects of Changes in Viscosity on Fracture Surface AppearanceL. Deibler*, J. Lewandowski, Case Western Reserve University, USA

The purpose of this study is to examine how changes in viscosity af-fect the fracture surface observations on a model test system, and toapply the knowledge gained to the tensile properties of amorphousMg85Cu5Ca10 ribbons. Experiments were first conducted on tensilesamples constructed to contain liquids of different viscosity that weretested at different temperatures. Metallic glass ribbons were subse-quently tested in tension at various temperatures up to and beyondthe glass transition temperature and examined via SEM. The differentviscosities produced via changes in test temperature and or initial liq-uid viscosity affected both flow behavior and fracture appearance.The results will be discussed in the light of the various models forflow and fracture in such systems.

Materials & Systems: Enabling SurfaceCoating Systems: Science and Technology

Thermal Barrier Coatings IRoom: 335Session Chairs: Dongming Zhu, NASA-Glenn Research Center;Rodney Trice, Purdue University

8:00 AMFactors Affecting Thermal Barrier Coating Failure Across MultipleBond Coating/Superalloy Systems (Invited)E. Jordan*, M. Gell, University of Connecticut, USA; F. Wu, SichuanUniversity, China

The failure behavior of thermal barrier coatings (TBCs) is most typi-cally investigated using a single top coat/ bond coat/ base alloy sys-tem. In this study, multiple TBC systems were subjected to cyclic fur-nace tests and examined and two questions are considered (1) Whatbond coat factors correlate with cycles to failure? and (2) Which fail-ure mode is the most common across all TBC systems? From this re-search, the growth rate of the thermally grown oxide layer on thebond coat is shown to be most predictive of failure life. The failuremode involving bond coat asperities is found to be the most com-mon. Surprisingly, samples with air plasma sprayed bond coats, thatexperience extensive internal oxidation were among the most durable

8:40 AMBehavior of Thermal Barrier Coatings in Thermal GradientConditionsJ. C. Day*, D. R. Clarke, University of California, Santa Barbara, USA

Under engine use conditions, thermal barrier coatings (TBCs) are sub-ject to high thermal gradients (TG). Understanding of behavior andfailure mechanisms due to TG exposure is essential to predict TBC life-times. We exposed EB-PVD TBC coated buttons to high TG created byCO2 laser heating of the top coat and passive water cooling of the su-peralloy. A number of phenomena have been observed. Sintering ofthe top coat occurs toward the TBC surface due to higher temperaturesand lower constraint. Additionally, we observed the unexpected for-mation of voids in the bond coat. The formation of voids suggests thatsignificant stresses form within the bond coat. During TG loading, sur-face temperature of the TBC was monitored using infrared thermom-etry. Sudden spikes in temperature, after extended TG exposure, sug-gest that voids form at high temperature and contribute to failure ofthe TBC. These observations, together with microstructural analysis,will be placed into context of the behavior of TBCs under severe TG.

9:00 AMModulated TBCs for FOD resistanceM. W. Crowell*, R. M. McMeeking, A. G. Evans, UCSB, USA

Thermal barrier coatings (TBCs) for high pressure turbine (HPT)blades in aeroengines are typically applied by electron-beam physi-

cal vapor deposition (EB-PVD) resulting in a columnar microstruc-ture. Process modifications can impart modulations or “waviness” tothe usually straight columns, and engine experience has suggestedthese modulations give greater resistance to foreign object damage(FOD). But because manufacture and engine testing of a wide vari-ety of modulated TBCs is infeasible, and current laboratory testingmethods do not replicate engine FOD conditions, modulation is avirtually untapped design space. We have used a microstructure-based dynamic finite element model with associated spallation met-ric to simulate a variety of TBC geometries and engine FOD scenar-ios, including a systematic treatment of parameters such astemperature gradient and particle size, speed, and impact angle.Modulated TBCs are found to have potential performance advan-tages under significant temperature gradients and oblique impactangles.

9:20 AMComputational, Experimental and Data Mining Approach forLifetime Assessment of Thermal Barrier CoatingsA. Luz*, D. Balint, K. Nikbin, Imperial College London, United Kingdom

Thermal barrier coatings are widely employed in various gas tur-bine engines for aircraft propulsion and power generation. A thinceramic coating is applied on critical components to improve theirhigh temperature, corrosion and oxidation resistance, in order toobtain higher efficiency. However TBCs have a limited life due tocrack nucleation and propagation, which leads to coating delami-nation and loss of thermal protection. The goal of this study was todevelop a new finite element model in order to understand themost critical parameters that affect the durability of TBCs, to allowthe development of materials that can prolong component life. Thethermo-mechanical properties used in the computational modelwere determined through a series of experiments carried out inseveral laboratories. Moreover, a handful of optical non-destruc-tive techniques were applied and a neural network was built tocombine their information and predict the lifetime of TBCs inservice.

10:00 AMSmall Angle X-ray Scattering Characterization of SuspensionPlasma Sprayed Yttria-stabilized Zirconia Coatings (Invited)K. Van Every, M. Krane, R. Trice*, Purdue University, USA

With the suspension plasma spray (SPS) process, DC plasma sprayingcan be used to produce coatings from nano-scale diameter ceramicparticles. The decrease in the microstructural feature sizes resultingfrom the nano-powder has implications for lowering the coatingthermal conductivity. Consequently, yttria stabilized zirconia coat-ings produced via SPS have been evaluated as thermal barriers. Thisstudy will present results on the amount and type of porosity in theas-sprayed and 1200°C heat-treated conditions of these coatings de-termined by the absorption and small angle scattering of synchrotronX-ray radiation. Additionally, the porosity findings will be correlatedto the results from laser flash thermal conductivity testing conductedon the same samples.

10:40 AMDevelopment of Hafnia and Zirconia double-layered TBCsproduced by EB-PVDK. Wada*, T. Fuse, Y. Ishiwata, Toshiba Corporation, Japan

Hafnia-based thermal barier coatings (TBCs) deposited by electronbeam physical vapor deposition (EB-PVD) have been developed forthe hot components in advanced gas turbines for power genera-tion. Although yttria-stabilized hafnia (YSH) has a high meltingpoint and a low thermal conductivity compared with a conven-tional yttria-stabilized zirconia (YSZ), the coefficient of thermalexpansion of the YSH is lower than that of the YSZ. In order to im-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 124

Tues

day

AM

www.matscitech.org 125

prove the thermal cycling resistance of this coating, we have carriedout the following improvements; (1) YSH/YSZ multi-layering, (2)compositionally-graded interface and (3) optimizing the mi-crostructure. Consequently, the developed YSH/YSZ double-lay-ered TBCs showed a sufficient low thermal conductivity at hightemperature (1.2 W/mK) and its thermal cycling resistance wasthree times as high as that of the plasma sprayed YSZ TBCs. Wehave successfully finished the fundamental studies of the hafnia-based TBCs.

11:00 AMDefining Optimal Roughness of the Bond Coat – Top CoatInterface in Air-Plasma Sprayed Thermal Barrier Coating SystemsM. D. Weeks*, D. R. Mumm, University of California, USA

Interfacial roughness plays a key role in the generation of compressiveand tensile stresses through oxide growth processes and microstruc-tural changes in thermal barrier coating (TBC) systems, but the cor-relations between bond coat (BC) roughness and coating lifetime forair-plasma sprayed TBCs have not been fully developed. This researchis aimed at developing an improved mechanistic understanding ofthe effect of BC – TBC interfacial roughness on the performance anddurability of these systems through three-dimensonal analysis ofbond interface morphology and linkages with local damage evolu-tion. A compilation of descriptive surface morphology parametershas been assembled to provide a more relevant description of inter-face morphology, relative to observed coating failure mechanisms.These parameters have been linked to experimental observations tofully characterize the damage evolution and failure of APS systems.

11:20 AMThe Effect of Solid Calcium Oxide Deposits on Degradation of AirPlasma Sprayed Thermal Barrier CoatingsK. Jung*, G. H. Meier, F. S. Pettit, University of Pittsburgh, USA

When gas turbines use alternate fuels, such as syngas derived fromcoal, CaO may deposit on turbine hardware. To study the CaO in-duced degradation of the thermal barrier coating (TBC) systems, aTBC system with and without solid CaO deposits was isothermallyexposed at 950oC in dry air. The TBC system consisted of a René N5substrate, a NiCoCrAlY bond coat and an air plasma sprayed (APS)yttria-stabilized zirconia (YSZ) topcoat. Surface morphologies andmicrostructures of cross-sections of exposed specimens were charac-terized with the optical and scanning electron microscopes alongwith EDX element mapping analyses. Specimens coated with CaOdeposits formed calcium zirconates on topcoat due to the reactionbetween the oxide deposit and the YSZ. It is proposed that CaO de-posits will have adverse effects on TBCs due to spalling of the reactionproducts during thermal cycling.

11:40 AMA Numerical Study of Microstructural Development in PlasmaSprayed CoatingsJ. M. Yanke*, R. Trice, M. Krane, Purdue University, USA

The development of the microstructure of plasma sprayed ceramiccoatings is simulated with a numerical model of droplet impact andsolidification. The model uses a volume of fluid (VOF) trackingmethod coupled with a 2D fluid dynamics code based on the SIM-PLER algorithm and a non-equilibrium solidification model. The ef-fects of the droplet temperature, substrate temperature, and impactspeed on the splat morphology and solidification rate are investi-gated and compared to experimental data. Also, a range of initialdroplet diameters (0.5 to 50 μm) is used to simulate different spray-ing conditions. A method of tracking multiple droplet impacts isused to simulate the deposition of a coating, allowing a study of thechanges in splat morphology and solidification rate with thickness ofthe coating.

Materials & Systems: Glass and OpticalMaterials

Glass and Optical Materials IIRoom: 334Session Chair: Mario Affatigato, Coe College

10:00 AMGlasses with Fictive Temperature Independent Properties:Minimum of Indentation Size Effect and Maximum in IndentationCrack ResistanceT. M. Gross*, M. Tomozawa, A. Koike, Rensselaer Polytechnic Institute, USA

Glasses can be characterized as normal or anomalous depending ontheir fictive temperature-property relationships. Intermediate be-tween normal and anomalous glasses are glasses which exhibit fictivetemperature independent properties. It was determined that glasseswhich exhibit fictive temperature-independent density and hardnesswill give a minimum in the indentation size effect, i.e. the load de-pendence of hardness. Glasses that exhibit a minimum in fictive tem-perature dependence of Young’s modulus were found to exhibit amaximum in indentation crack resistance, although the high mois-ture sensitivity of high silica glasses was found to limit the crack re-sistance for these glasses. The fictive temperature dependence of theseproperties is related to these indentation phenomena through an in-dentation induced fictive temperature increase.

10:20 AMRelationship between dissolution amounts of B2O3 and R2O (R =Na, K) and phase separated compositions of SiO2-rich borosilicateglass (SiO2-B2O3-R2O)M. Okamoto*, Hitachi Ltd., Japan; H. Tanei, Industrial PropertyCooperation Center, Japan; M. Nakamura, S. Iwanaga, E. Takane, S. Ishihara,Hitachi Ltd., Japan

The relationship between the amounts of B2O3 and R2O (R = Na, K)dissolved in water from the surface area of borosilicate glass powderand borosilicate glass (SiO2-B2O3-R2O) compositions in the rangeof SiO2:75-90 mol%, B2O3:5-20 mol%, and R2O:0-15 mol% wereinvestigated. For the SiO2-B2O3-K2O type glass, the amount ofB2O3 dissolution increased monotonously with the increase in theB2O3 content, and the amount of K2O dissolution also increasedmonotonously with the decrease in SiO2 content. On the other hand,for the SiO2-B2O3-Na2O type glass, although a similar tendency tothe K2O type glass was observed, a glass composition area was found,in which the amount of B2O3 and Na2O dissolution was very large,and was located in a B2O3 rich area of the investigated compositions.These areas correspond to phase separated compositional areas of theSiO2-B2O3-Na2O type glass.

10:40 AMHazardous Sulfate Ion Removal from a Solution by BorosilicateGlassesJ. Nam*, C. Kim, Inha university, South Korea

In this study, the sulfate ions in a solution have been removed byusing borosilicate glass. Glasses with various compositions in the sys-tem of SiO2-Na2O-B2O3-RO (R=Mg, Ca, Sr, Ba) were prepared. Theglasses were reacted in a solution containing sulfate ions with differ-ent concentration for various times. The sulfate ion concentration inthe reacted solution was measured and the glass surface after reactionwas analyzed by XRD and SEM. Sulfate ions in the solution werecombined with divalent ions leached out of glass to precipitate on theglass surface as sulfate crystals. The sulfate ion can be removed fromthe wastewater in this manner. The sulfate ion removal capacity isclosely related to the solubility product constants of the newly formedsulfate crystals. The sulfate crystals were easily formed on the glasscontaining either SrO or BaO. Generally, sulfate ion removal capacitywas quite high by using borosilicate glasses.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 125

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania126

11:00 AMA Comparison of Atomic Packing in Alkali and Alkaline-EarthGlass SystemsS. Feller*, M. Burgess, D. McClarnon, M. Affatigato, Coe College, USA

Packing is an intrinsic property of glass, defined as the ratio of ionicvolume to molar volume, and is a useful parameter for analyzingstructural changes with composition. Alkali based glasses show twotrends in packing, one dominated by the oxygen covalent network forthe small ions, Li and Na, and one ionically dominated by the metalcations for the large, K, Rb and Cs cases. We have found that alkaline-earth glasses do not display these behaviors, and in this presentationwe determine the packing fractions of these glasses and comparethem with the alkali case. Further, we consider the structural implica-tions of the packing trends

11:20 AMQuaternary NLO MaterialsN. B. Singh*, D. Knuteson, K. Green, G. Kanner, S. Kelley, A. Berghmans, D.Kahler, B. Wagner, S. McLaughlin, Northrop Grumman Corporation, ES, USA

The ideal requirements for NLO materials are very difficult to meet ina single material. Optical homogeneity, laser damage threshold, sta-bility of the compound upon exposure to laser beam, and ease of fab-rication are main concerns. Another requirement is to scale up thecrystal size to achieve high efficiency and high power output withoutsacrificing the optical quality. All of the nonlinear materials that canbe considered for applications have problems that severely limit theperformance and efficiency of the systems. Some of the problemsmay be reduced by advances in crystal growth and fabrication tech-nology; other problems are intrinsic to the materials. We report anovel class of nonlinear optical crystal, synthesis, crystal growth andsome of the relevant properties for its applications into visible to far-infrared wavelength region. These are quaternary materials with alarge flexibility to design transparency, damage threshold and effec-tive performance coefficient “d2/n3” for frequency conversion havebeen developed.

Materials & Systems: InternationalSymposium on Innovative Processing andSynthesis of Ceramics, Glasses andComposites

Microwave and Plasma ProcessingRoom: 336Session Chair: Dinesh Agrawal, Pennsylvania State University

8:00 AMApplication of Microwave Energy for High-Temperature MaterialsProcessing (Invited)D. Agrawal*, Pennsylvania State University, USA

Application of microwave energy is emerging as an innovative tech-nology for the processing of variety of materials at faster rates,cheaper processing cost, and in most cases with better properties.Since the first application of microwave during World War II forradar, it has found its utility in numerous diverse fields making itthe most versatile form of the energy for materials processing. Ini-tially microwave energy has been successfully applied in many lowtemperature (<500°C) applications such as rubber vulcanization,food processing, wood curing, textiles, polymers, biochemistry etc.In the last two decades many new developments have occurredworldwide in the microwave research area that has made the mi-crowave heating very attractive for high temperature applications(>500°C) involving ceramics, composites, semiconductors and met-als. This presentation will provide an overview of high temperature

microwave applications including its commercialization effortsworldwide.

8:40 AMScience Behind Novel Energy Saving Ceramic Microwave Ware(Invited)S. Komarneni*, The Pennsylvania State University, USA; H. Katsuki, SagaCeramic Research Laboratory, Japan

Ceramics of novel Fe2O3 – Li2O – SiO2 – Al2O3 composition madefrom a mixture of Fe3O4 and petalite mineral have been discoveredto get rapidly heated under microwave irradiation and have relativelyhigh heat energy holding ability compared to the presently used com-mercial ceramics. The Fe3O4 component transformed to Fe2O3 is re-sponsible for microwave-assisted rapid self-heating of the compositesand the relatively low thermal conductivity of these composites leadsto their high heat holding ability. These novel ceramics are beingcommercialized as microwave ware. They also have potential applica-tions in remediation of organic contaminants by facilitating ultrafastdecomposition upon microwave irradiation as demonstrated withcooking oil as an example.

9:20 AMMicrowave Technology for Enhanced Binder RemovalM. L. Fall*, H. S. Shulman, S. M. Allan, Ceralink Inc, USA

Microwave heating technology is useful to accelerate binder re-moval for ceramics, powder metal parts and composites. Organicbinders generally couple well with microwave energy, allowing uni-form heating. Microwave heating is not dependent on thermalconduction from the surface of the part inward, resulting in fasterheating. This helps to prevent defects caused by conventional heat-ing, in which binder may be trapped within the part as surfacepores close. Instead, the binder is heated within the part and mi-grates out from the center to the surface. The absorption of mi-crowave energy is affected by the dielectric properties of the mate-rial and the binder. The dielectric properties of several materialswith and without binder have been measured, and provide under-standing as to how the microwave energy interacts with the mate-rials. The dielectric properties were useful in developing mi-crowave binder-removal processes for lab and production scaleprocessing.

10:00 AMMicrowave Assist Technology for Ceramic ProductionM. L. Fall, S. M. Allan, H. S. Shulman*, Ceralink Inc, USA

Microwave Assist Technology (MAT) combines radiant energy withmicrowave heating to achieve energy and time savings, as well asproperty improvements. MAT was used to fire ceramic compositesused as sleeves in the power generation industry. Feasibility was con-ducted in a lab-scale MAT kiln, where process parameters were ex-plored in designed experiments. The process was scaled up into a 30cubic foot, atmosphere controlled MAT kiln, built by Harrop. Theproduct was found to fire successfully at least 5 times faster in theMAT kiln. The results from these tests will be discussed, including theenergy, properties, and scale up considerations.

10:20 AMContinuous microwave-driven polyol process for synthesizingytterbium-doped yttria powderM. Imam*, A. W. Fliflet, K. L. Siebach, A. David, R. W. Bruce, S. B. Qadri, C.R. Feng, S. H. Gold, Naval Research Laboratory, USA

The continuous microwave polyol process is a promising novel ap-proach to the synthesis of metallic and ceramic nanopowders. Cur-rent efforts are directed toward synthesizing ytterbium-doped yttria(Yb:Y2O3) for use as a polycrystalline laser host material. The

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 126

Tues

day

AM

www.matscitech.org 127

process involves pumping a mixture of yttrium nitrate and ytter-bium nitrate dissolved in hydrated diethylene glycol through a pres-surized quartz tube contained in an S-Band waveguide driven by a2.45GHz microwave source at powers up to 6 kW. As the solutionmoves along the waveguide, it absorbs the co-propagating mi-crowave energy and is heated rapidly to a temperature above 200Ccausing a reaction to occur. Condensation reactions then form parti-cles with ytterbium-doped yttria crystal structure. The rapid heatingand cooling serve to limit the growth of the crystals so that they areon submicron. The production of doped yttria was confirmed by x-ray diffraction.

10:40 AMMicrowave Irradiation-assisted Method for the Rapid Synthesis ofFine Particles of αα-Al2O3 and αα-(Cr1-xAlx)2O3 and theirCoatings on SiA. Gairola*, A. M. Umarji, S. A. Shivashankar, Indian Institute of Science, India

Pure and Cr-substituted Al-acetylacetonate have been synthesizedand employed as precursors for a novel soft chemistry process,where microwave irradiation of a solution of the complex yieldswell-crystallised needles of α-Al2O3 and α-(Cr1-xAlx)2O3,(0<x<1)measuring ~0.02μm dia and 0.1μm long, withinminutes. By varying the microwave radiation parameters and using asurfactant such as PVP, the crystallite size and shape can be con-trolled and their agglomeration prevented. These microstructuralparameters, and the polymorph of Al2O3 formed, may also be con-trolled by employing a different complex, e.g., Al-dipivaloyl-methanate. Samples of α-Al2O3 and α-(Cr1-xAlx)2O3 have beencharacterized by XRD, FTIR and TEM. The technique results in ma-terial of homogeneous metal composition, which can be adjusted asdesired, as shown by EDAX. The technique has been extended to ob-tain large area, adherent coatings of Al2O3 and Cr-Al2O3 on Si at~0.1μm/min.

11:00 AMMechanical Properties and Corrosion Behavior of Microwave -Vacuum Sintered Aluminum AlloysP. Chandran*, D. Agrawal, A. Upadhyaya, Indian Institute of Technology,Kanpur, India

This study deals with role of vacuum atmosphere in microwave andconventional sintering of 2712 and 6711 aluminum alloys leading tohigher densification rates. The Al alloy compacts were sintered at var-ious temperatures ranging from 570 to 630°C for 1hr in vacuum at-mosphere (1 x10-5 to 1x10-6 Torr) in both heating modes. The den-sification behavior was well investigated through dimensionalchanges and dilatometric curves. The microstructural and phaseanalysis were done in order to understand the sintering mechanisminvolved during vacuum sintering. It was found that ultimate tensilestrength, elongation, transverse rupture strength and corrosion be-havior were improved due to finer grain size in case of microwave sin-tering as compared to conventional counterparts. The vacuum sin-tered samples were investigated in comparison with nitrogen sinteredin case of both heating modes for better understanding of properties.

11:20 AMLarge scale synthesis of nanoscale hydroxyapatite powders usinginduction plasma sprayM. Roy*, A. Bandyopadhyay, S. Bose, Washington State University, USA

Calcium phosphate (CaP) materials, especially hydroxyapatite(HAp) and tricalcium phosphate (TCP), gained significant impor-tance as bone substitutes, fillers and coating materials. It has been re-ported that nanoscale features of CaP materials improve both bio-logical and mechanical properties. HAp nanopowder wassynthesized using induction suspension plasma spray system withHAp sol as precursor. The sol was axially fed into the RF plasma jet at

different plasma powers. Based on the particle size, as synthesizedpowders were collected at different chambers. The particle size, sur-face area, morphology and phase composition of the synthesizedpowders were characterized using TEM, XRD, FTIR, particle size an-alyzer and BET surface area. The finer particles synthesized in thesize range of 40-80 nm were spherical in nature. The presentationwill focus on influence of different induction plasma spray parame-ters on synthesized HAp nanopowder particle size, phase composi-tion and process yield.

Nanotechnology: Controlled Processing ofNanoparticle Structures and Composites

Nanoparticle Sintering IIRoom: 408Session Chair: Nikhilesh Chawla, Arizona State University

8:00 AMLiquid-Feed Flame Spray Pyrolysis (LF-FSP): Production andProcessing of Novel Nano-oxide Materials (Invited)R. M. Laine*, J. C. Marchal, J. Azurdia, M. Kim, University of Michigan, USA

LF-FSP of metal alkoxide and carboxylate complexes dissolved inethanol generates a wide variety of phase pure single and mixed-metal oxide nanopowders. Recent advances in experimental pa-rameters and system variables allow exploration and control thephases, morphology and size distributions of LF-FSP derived par-ticles. The evolution of the synthesis process provides access tovery novel materials with standard phase compositions giving un-expected phases as well as difficult or otherwise impossible toachieve stoichiometries within known phase fields. An under-standing of the mechanisms of formation of these unexpectedproducts provides a better understanding of nano-particle forma-tion, evolution and processing behavior. This talk will focus on thegeneration of core-shell systems and their sintering and catalyticproperties.

8:40 AMDesign of the Electroceramics for Solid Oxide Fuel CellApplications: Playing with Ceria (Invited)V. Esposito*, E. Traversa, Università di Roma “Tor Vergata”, Italy

Ceria and acceptor-doped ceria compounds are currently in use inseveral technological applications. Nanostructured ceria-based mate-rials present peculiar properties and have been considered to enhancethe electrochemical performance of fuel cells. Acceptor-doped ceriashowed in some cases anomalous grain growth and grain size may af-fect the the electrical conductivity inducing the formation of anom-alous dopant nano-domains. Although those nano-sized ceramics ex-hibit rapid sintering at lower temperatures, it is difficult to control thegrain growth during the sintering process. The combined effect ofgrain size and doping content on the electrical properties of denselayers was evaluated. Tunable microstructures, from the startingnano-powders, were developed for the fabrication of IT-SOFC elec-trolytes. The influence of grain size and microstructure on the electri-cal and mechanical properties of dense bodies was investigated.

9:20 AMNi-B Nanolayer Evolution on Boron Carbide Particle Surfaces atHigh TemperaturesK. Lu*, X. Zhu, Virginia Polytechnic Institute and State University, USA

This study is focused on reduction of Ni2O3 and B2O3 in the Ni-Bnanolayer on B4C particle surfaces and understanding of thenanolayer composition and morphology changes. Scanning electronmicroscopy is used to examine the Ni-B nanolayer morphology evo-lution. X-ray photoelectron spectroscopy is used to study the Ni-Bnanolayer composition change. X-ray diffraction is used to analyze

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 127

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania128

the Ni-B nanolayer phases at different temperatures. For the as-coated B4C particles, the nanolayer contains Ni2O3, B2O3, andamorphous boron. After 400°C thermal treatment in a H2-Ar atmos-phere, Ni2O3 is reduced to nickel; the nanolayer morphology ismaintained and the coated particles demonstrate magnetism. As thetemperature is increased to 550°C, B2O3 is reduced to boron, whichreacts with nickel and forms Ni2B. Simultaneously, the nanolayerevolves into nanoparticles. Thermal treatment temperature increaseto 700-900°C only causes Ni2B particle growth but does not funda-mentally change the composition or phase.

10:00 AMDense Nanocrystalline Hydroxyapatite Fabricated viaMorphology-Enhanced Low Temperature Sintering (Invited)J. Wang, L. Shaw*, University of Connecticut, USA

Dense hydroxyapatite (HA) bodies (> 99% of the theoretical) are at-tained via pressureless sintering at 850 and 900 C. These are the low-est sintering temperatures for dense HA bodies ever reported in theliterature. The starting HA nano-rods with high aspect ratios are es-sential for attainment of dense HA bodies at sintering temperaturesbelow 900 C. The high surface energy stored in nano-rods with highaspect ratios induces the morphology change and provides increaseddriving force for densification. The side surfaces of nano-rods offerfast diffusion paths with a low activation energy (89 kJ/mol). Thisnew mechanism for enhancing diffusion and driving force for densi-fication opens up possibilities to obtain advanced ceramics and com-posites with improved properties or new functionalities via low tem-perature sintering.

10:40 AMLink between Microstructure Evolution and Sintering Kinetics forAggregated Nanocrystalline Powders (Invited)I. Nettleship*, University of Pittsburgh, USA

The commonly used approach for explaining the effect of particle ag-gregation on microstructure evolution and the consequences for sin-tering kinetics will be reviewed. The implicit assumptions in this ap-proach result in grain size being the only microstructural length scalerepresented in the kinetic equations of sintering. It is therefore notsurprising that the effects of aggregation and particle packing on thedensification of nanocrystalline powders continues to be interpretedlargely in terms of their effects on grain growth. This reliance ongrain size will be criticized and relative merits and weaknesses of al-ternative modeling and experimental methods will be discussed interms of their ability to accommodate the effects of particle aggrega-tion and packing.

11:20 AMThe Relationship between Microstructure and Sintering Kineticsfor Aggregated Nanocrystalline PowdersT. Chen*, I. Nettleship, University of Pittsburgh, USA; T. R. Hinklin, K. G.Ewsuk, Sandia National Laboratory, USA

In traditional models of sintering where grain size is assumed to beproportional to diffusion distance, average grain size is used as ameasure of microstructural scale to predict densification kinetics.Unfortunately, this assumption may not be valid for the heteroge-neous microstructure of an aggregated nanocrystalline powder. Anew effective diffusion length that is sensitive to the local arrange-ment of pores has been defined based on pore boundary tessellation.This presentation will show that this new effective diffusion lengthlinks microstructure and sintering kinetics for denification controlledby volume diffusion. Implications for densification controlled bygrain boundary diffusion will also be discussed. Sandia is a multipro-gram laboratory operated by Sandia Corporation, a Lockheed Martincompany, for the United States Department of Energy’s National Nu-clear Security Administration under contract DE-AC04-94AL85000

Nanotechnology: Nanotube-Reinforced MetalMatrix Composites

Properties of Nanotube MMCsRoom: 409Session Chair: Sudipta Seal, University of Central Florida

8:00 AMUsing Carbon Nanotubes to Enhance the Thermal and MechanicalProperties of Metallic Materials (Invited)M. Gupta, M. Nai*, C. Goh, J. Wei, National University of Singapore,Singapore

Different weight percentages of carbon nanotubes (CNTs) were in-corporated into lead-free (SnAgCu) solder and magnesium (Mg), re-spectively, to synthesize two new sets of nanocomposites. The com-posites were fabricated using powder metallurgy technique followedby extrusion. The effects of CNTs on the physical, thermal and me-chanical properties of composites were investigated. Thermo-me-chanical property results revealed an increase in thermal stabilitywith increasing amount of CNTs in both SnAgCu and Mg compos-ites. Mechanical property characterizations revealed enhanced overallstrength for both systems. For Mg-CNT composites, ductility andwork of fracture were also observed to improve with increasing addi-tion of CNTs. For SnAgCu-CNT composites, creep tests performedon solder joint samples showed better creep resistance with increas-ing addition of CNTs. An attempt is made in this study to correlateproperties of the resultant nanocomposites with increasing amountof CNTs.

8:40 AMStrengthening behaviors in aluminum based nanocompositescontaining homogeneously aligned carbon nanotubes (Invited)D. Bae*, H. Choi, Yonsei University , South Korea

Aluminum based nanocomposites exhibiting high specific strengthare fabricated by hot rolling of the ball-milled mixture of aluminumpowders and MWNTs (Multi-walled carbon nanotubes). Each ofMWNTs is well dispersed during the milling and uniaxially alignedalong the rolling direction. Especially, the tubes are found to be grad-ually filled with aluminum atoms as the milling time increases, pro-viding the perfectly sticking interface between the MWNTs and thematrix. For the composites, boundary strengthening (refining grainsize) is also employed together with composite strengthening. . Thereinforcing efficiency of MWNTs in the composites under tensiletests follows the volume fraction rule of discontinuous fibers in thegrain size range down to 70 nm, but the MWNTs in the compositeswith grain size below 70 nm cannot transfer load effectively due tothe dynamic recovery processes of aluminum.

9:20 AMCarbon Nanotube Reinforced Nickel Matrix CompositesJ. Hwang*, A. Singh, T. W. Scharf, University of North Texas, USA; J. Tiley, AirForce Research Laboratory, USA; R. Banerjee, University of North Texas, USA

Composites based on multi-walled carbon nanotubes (MWCNT)dispersed in a nickel matrix have been processed using the laser-engineered net shape (LENS) processing technique. The advantageof using LENS is that that while using a powder feedstock, thecomposites are processed via a liquid metal route involving rapidsolidification. The present study focuses on two aspects, the sur-vivability of nanotubes during melt processing using LENS in aliquid nickel matrix, and the structure and chemistry of the inter-face between the nanotubes and metal matrix. Furthermore, thestability of MWCNT versus graphite powders in liquid nickel havebeen compared by processing both types of composites underidentical conditions. These composites have been characterized indetail using scanning electron microscopy (SEM), transmissionelectron microscopy (TEM), and, micro-Raman spectroscopy. The

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 128

Tues

day

AM

www.matscitech.org 129

microhardness and the wear resistance of the MWCNT reinforcedcomposites have also been studied and these results will also bepresented.

10:00 AMEffect of addition of Ni and Ag on Cu-CNT composite’s electricalconductivity (Invited)N. Munroe, S. Amruthaluri*, P. K. Gill, W. Haider, Florida InternationalUniversity, USA

Copper-Carbon nanotube (Cu-CNT) composites are of great interestdue to their wide range of applications in electrical appliances. In re-cent years the researchers have shown lot of interest in this composite.Powder metallurgy technique was used to prepare Cu-CNT compos-ite with addition of Silver (Ag) and Nickel (Ni). Different composi-tions were prepared for comparative analysis. Enhancement in elec-trical conductivity of this composite was observed by using fourprobe method. Scanning Electron Microscopy (SEM) and X-raymapping showed homogenous mixing of CNTs in the composite.This composite overcomes the limitations of interfacial bonding inCu-CNT matrix and homogenous distribution of CNTs. Our investi-gation demonstrated that addition of Ag and Ni resinates changes themorphology of the composite by increasing the interfacial bondingbetween Cu and CNT.

10:40 AMHighly Conductive Nanostructure Cu-Cr-MWCNT CompositeN. D. Munroe, P. S. Gill*, S. Amruthaluri, W. Haider, Florida InternationalUniversity, USA

Contact materials for medium voltage and high current Vacuum Cir-cuit Breakers are required to possess excellent electrical and thermalconductivity, as well as superior mechanical strength. Cu-Cr alloysreinforced with Multiwalled Carbon Nanotubes (MWCNT) appearto be an excellent candidate for this application. A powder metallur-gical technique was used to prepare high density compacts of Cu-Cralloy with varying percentages of MWCNT. The morphology of thecomposites was studied by employing SEM/EDS, XRD, TEM andRaman Spectroscopy. The electrical conductivity and Vickers hard-ness of the compacts were also determined. A substantial increase inthe electrical conductivity and strength of the composite was at-tained upon the addition of 5-10 % of volume fraction MWCNT.

11:00 AMSynthesis and characterization of plasma spray formed carbonnanotube reinforced aluminum compositeE. p. Yedidi*, osmania university college of technology, India

A trend has been perceived in the field of composite materials to em-ploy carbon nanotubes as reinforcement in synthesizing composites ofunique properties. In this endeavor, free standing structures of Al-basednanostructured composite with carbon nanotubes as second phase par-ticles has been synthesized by plasma spray forming technique. Opticalmicroscopy, scanning electron microscopy, X-ray diffraction, transmis-sion electron microscopy has been carried out to analyze the compositestructure and to verify the retention of carbon nanotubes. Besides, den-sity and microhardness measurements have been performed to under-stand the effect of carbon nanotube reinforcement on the mechanicalproperties of the composite. The characterization affirms the presenceof unmelted and chemically unreacted carbon nanotubes in the com-posite. Moreover, the composite experienced an increase in relative mi-crohardness due to the presence of carbon nanotube.

11:20 AMFunctionalization of Single Walled Carbon Nanotubes with 2-methyl Aziridine CompoundA. Hussain, K. Nawaz*, T. Noor, National University of Science andTechnology, Pakistan; S. Niazi, I. Akhtar, Qaid-e-Azam University, Pakistan

The functionalization of SWCNT’s was carried out in three stepsstarting with oxidization of CNT’s by acid treatment of as received

material with four molar nitric acid as an oxidizing agent for 24 hoursat 105C. This treatment attaches –COO- group to the CNT’s surfacefollowed by the protonation of sample by sonication in presence of1M HCl for 2 hours. These nanotubes were washed with de-ionizedwater. The attachment of –COOH group was confirmed by its FTIRanalysis. Later on oxidized CNT’s were chlorinated with thionyl chlo-ride in the presence of dimethyl formamide as a catalyst. Then thenanotubes were washed with anhyderous tetrahydrofuran. Thesechlorinated tubes were reacted with 2-methylaziridine. The aziridinefunctionalized nanotubes were thoroughly washed with anhydrousbenzene till neutralization of CNT’s. The attachment of aziridinewith CNT’s was confirmed by FTIR and elemental analysis, alongwithAFM images.

Processing & Product Manufacturing:International Symposium on Ceramic MatrixComposites

Ultra High Temperature Ceramics and CompositesRoom: 413Session Chairs: Sylvia Johnson, NASA Ames Research Center;Gregory Hilmas, Missouri University of Science & Technology

8:00 AMAdvances in Processing of Ultra High Temperature Ceramics atNASA ARC (Invited)S. M. Johnson*, NASA Ames Research Center, USA; M. Stackpoole, ELORETCorp. / NASA Ames Research Center, USA; M. Gasch, NASA Ames ResearchCenter, USA; M. Gusman, J. Thornton, ELORET Corp. / NASA AmesResearch Center, USA; E. Irby, NASA Ames Research Center, USA

NASA ARC has completed extensive work in the development of re-fractory, oxidation-resistant diboride UHTC composites. The high-temperature properties of these composites make them good candi-dates for leading edge applications for reusable reentry vehicles.Mechanical and thermal performance of baseline UHTC materials islower than desired (re fracture toughness, oxidation resistance, andthermal shock) because of the microstructural architecture compris-ing SiC particulates in a metal boride/carbide matrix. Current re-search focuses on processing unique microstructures using (1) a pre-ceramic polymer route to produce high-aspect ratio reinforcementsin situ, (2) addition of third phases to promote microstructural re-finement, and (3) a novel fluidized-bed reactor CVD approach tocoat diborides and control grain boundary composition. All ap-proaches yield unique microstructures with potentially enhancedthermal and mechanical properties, which will be discussed in thispresentation.

8:40 AMEffect of Oxygen Impurity Content on the Microstructure andProperties of Zirconium DiborideM. J. Thompson*, B. Fahrenholtz, G. Hilmas, Missouri University of Scienceand Technology, USA

Zirconium diboride ceramics with a range of oxygen contents weredensified by hot pressing, pressureless sintering, or spark plasma sin-tering. Oxygen impurities present in boride ceramics cause coarsen-ing, which inhibit densification. All of the zirconium diboride ceram-ics, regardless of oxygen content, could be processed to nearlytheoretical density by hot pressing or spark plasma sintering. How-ever, the addition of a sintering aid, carbon in this study, was re-quired to allow for densification by pressureless sintering. Carbon re-acted with and removed the oxide impurities that inhibiteddensification, which enabled zirconium diboride to reach at least95% relative density by pressureless sintering at temperatures as lowas 1800°C. The zirconium diboride ceramics were characterized tounderstand the effect of oxide impurity content, densification

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 129

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania130

method, and sintering temperature on relative density, hardness,grain size, and grain aspect ratio.

9:00 AMMechanical properties of zirconium diboride ceramics at elevatedtemperaturesS. Zhu*, W. G. Fahrenholtz, G. E. Hilmas, Missouri University of Science andTechnology, USA

Despite the proposed applications at high temperatures, few studieshave reported the mechanical properties of zirconium diboride(ZrB2) ceramics at elevated temperatures. In the present work, thefracture strength of ZrB2 ceramics was studied from room tempera-ture to 1500°C in air using four-point bending. At temperaturesabove 1200°C, significant loss of strength and Young’s modulus, aswell as creep, was observed. Further, the effect of surface oxidation onthe high temperature mechanical properties was examined. A combi-nation of SEM and TEM characterization was used to identify the mi-crostructural features which dictated the high temperature mechani-cal behavior. Softening of grain boundary glassy phases may accountfor strength and Young’s modulus decreases above 1200°C. Efforts toengineer the grain boundary phases could be promising for improv-ing the high temperature stability of ZrB2 ceramics.

9:20 AMEffect of SiC Particle Size on Mechanical Properties of PressurelessSintered ZrB2-SiC CeramicsS. Zhang*, G. Hilmas, W. Fahrenholtz, Missouri University of Science andTechnology, USA

The effects of the starting SiC particle size and the amount of carbonadditive on the densification and mechanical properties of ZrB2-SiCceramics were investigated. ZiB2 ceramics containing from 10 to 30vol.% SiC particles were densified (relative density >98%) by pres-sureless sintering using C and B4C as sintering aids. The pressurelesssintered ZrB2-SiC ceramics had a Vickers’ hardness of 22 GPa, elasticmodulus of ~ 500 GPa, and a fracture toughness of 3.5- 4 MPam1/2,regardless of the SiC and C contents. The highest flexure strength was~600 MPa. Microstructure analysis indicated that excess carbon re-mained at the grain boundaries for carbon contents > 5wt.% andlowered the flexure strength. Varying the size of the starting SiC par-ticles affected both the ZrB2 grain size and the final SiC grain size andmorphology. The SiC grain morphology could be varied fromequiaxed to whisker-like, which affected the resulting properties.

10:00 AMMicrostructure, phase development, and mechanical behavior ofreaction sintered and reaction hot pressed ZrB2-SiC particlecompositesH. J. Brown-Shaklee*, W. G. Fahrenholtz, G. E. Hilmas, Missouri Universityof Science and Technology, USA

Dense ZrB2-SiC composites were reaction processed from ZrH2,ZrC, SiB6, and ZrSi2 precursors. XRD indicated that gradual for-mation of ZrB2 occurred at the expense of ZrC between 1000°Cand 1450°C which suggests that self-propagating high-tempera-ture synthesis was suppressed despite the strong exothermic natureof the reactions (ΔHRXN ≈-400 kJ/mol). Reaction hot pressed(RHP) ZrB2-SiC exhibited room temperature flexural strength of800 MPa which decreased to 600 MPa at 1200°C in air. RHP com-posites contained submicron ZrB2 crystallites as well as grains inthe range of 1 to 3 μm. Rounded ZrB2 grains were found in RHPsamples near regimes of SiB6 suggesting that liquid phase forma-tion occurred at high temperature. Reaction sintered ZrB2-SiCachieved >95% density and contained a small amount of residualSiB6. Polished cross sections revealed elongated whisker- orplatelet-like α-SiC grains that exhibited aspect ratios approachingto 10:1.

10:20 AMMicro Raman stress measurements in ZrB2/SiC composites havingparticulate and engineered SiC additionsJ. Watts*, M. Teague, G. Hilmas, B. Fahrenholtz, Missouri University ofScience and Technology, USA

Previous research at Missouri S&T has demonstrated that the SiCparticulate size controls the strength of ZrB2-SiC ultrahigh tempera-ture ceramics (UHTCs). The current study has focused on the pro-duction of ZrB2 composites with varying sizes of SiC particulate, aswell as composites containing engineered SiC architectures. Finite el-ement modeling (FEM) was used to predict the areas of highest stressin ZrB2-SiC composites, and was used to design engineered SiC sec-ond phase shapes that would be expected to provide reduced internalstresses. Test specimens of each engineered architecture were pre-pared by hot pressing and machining into bars for 4-point flexuretesting. Micro Raman spectroscopy has also been employed in orderto measure the stress generated in the SiC additions during process-ing. Based on the measured compressive stress in the SiC, the maxi-mum tensile stress was calculated in the ZrB2 matrix.

10:40 AMMechanical Properties of TaC Based CeramicsX. Zhang*, G. Hilmas, B. Fahrenholtz, Missouri University of Science andTechnology, USA

Tantalum carbide (TaC) is one of several ultra-high temperature ce-ramics (UHTCs) being considered as a candidate material for propul-sion system components due to its ultrahigh melting temperature.Unfortunately, its mechanical properties have not been systematicallycharacterized due to the difficulty to fabricate dense parts. In thepresent study, tantalum diboride (TaB2) additions to TaC were foundto be effective in enhancing the densification of TaC. A relative den-sity of 98% was obtained by hot pressing at 2100C with 10 wt% TaB2additions. The densification behavior, microstructure, and mechani-cal properties, including flexure strength, modulus, fracture tough-ness, and Vickers hardness, were measured. The strength of TaC at el-evated temperature was also measured. The results of the study willbe presented and compared to the processing and properties of otherTaC ceramics in the technical literature.

11:00 AMReaction Processing of W-Ta2C CompositesM. Teague, G. E. Hilmas*, W. G. Fahrenholtz, Missouri University of Scienceand Technology, USA

Ditantalum carbide (Ta2C) is one of several ultra high temperatureceramics (UHTCs) regarded as a potential structural material for ex-tremely high temperature applications such as rocket nozzles and jetengine components due to its high melting point (3330�C), highhardness, and resistance to chemical attack and oxidation. Tungsten,due to its superior strength, high thermal conductivity, and highmelting point (3442�C), has been widely utilized in the latter appli-cations. W-Ta2C composites would be attractive due to their poten-tial for higher temperature use while maintaining a higher resistanceto thermal shock than Ta2C alone. Dense ceramic-metal compositeswere produced by reacting WC, Ta2O5, TaC, and C under vacuum at1450°C for 4 hours and then sintering at 1850°C for 1 hour. Phasecompositions were analyzed using x-ray diffraction and parallel elec-tron energy loss spectroscopy (PEELS). The flexure strength, fracturetoughness, and hardness of the composites will also be presented.

11:20 AMIn Situ Optical Microscopy of the Formation of Oxide Scales onZrB2-SiC during High Temperature OxidationS. Gangireddy*, S. Karlsdottir, J. W. Halloran, University of Michigan, USA

In situ optical microscopy is used to investigate the developmentof the oxide scale on ZrB2-15%SiC-2%MoSi2 ultra-high tempera-ture ceramic (UHTC) composites. Using a novel method of resis-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 130

Tues

day

AM

www.matscitech.org 131

tively heating a miniature, self-supported ribbon specimen, hightemperatures can be achieved at low power. This enables direct ob-servations of samples during oxidation in air at 1550°C. I will dis-cuss this experimental set up through which for the first time insitu optical microscopy of the specimen is made possible, yieldingvaluable information on the oxidation phenomena of UHTC. Di-rect observation confirms the hypothesis of formation and flow ofliquid oxides at high temperatures. Analysis of the R-G-B data inpixels of the digital in situ images enables the interpretation ofcontrast of the incandescent samples. Incandescent light contrastwas found to originate from emmissivity differences of surfacefeatures.

11:40 AMNovel optical microscopy for imaging beneath the surface of oxidescales on ZrB2-SiCS. Gangireddy, J. Tucker*, J. W. Halloran, University of Michigan, USA

Oxidation of ZrB2-SiC materials produces complex oxide scalewith opaque crystalline zirconium dioxide, transparent silica glass,and turbid borosilicate glasses. Metallographic microscopy of theoxidized ZrB2-15%SiC-2%MoSi2 composites under different imag-ing modes, Bright Field (BF), Dark Field (DF) and Indirect LightBright Field (ILBF), will be discussed. ILBF is a novel arrangementfor effecting dark field conditions using external light source. Ap-pearance of features in different illuminations, electron, BF andILBF is compared. DF and ILBF allow imaging of subsurface fea-tures under the transparent oxide layer and provide evidence offlow-patterns and liquid convection features, earlier found to beboron rich regions. Optical images will be compared with imagesfrom backscattered electron microscopy and cathodolumines-cence. Microstructural features are interpreted in terms ofprocesses involving the formation and transport of liquid oxidesolutions.

Processing & Product Manufacturing: Joiningof Advanced and Specialty Materials X

Friction Stir and Solid-State JoiningRoom: 410Session Chair: Leijun Li, Utah State University

8:00 AMFriction Stir Spot Welding of Advanced High Strength SteelsY. Hovanski*, G. J. Grant, Pacific Northwest National Laboratory, USA; M. L.Santella, Oak Ridge National Laboratory, USA

Friction stir spot welds were made in two advanced high-strengthsteels: DP780, and a hot-stamp boron steel. Numerous welds weremade with various plunge schemes that maintained weld times at orbelow 4 seconds. Rotational velocities and plunge rates were varied inorder to evaluate both single and multi-step plunge techniques. Anevaluation of the thermal and mechanical feedback characteristicsduring the friction stir spot welding process was made as it relates tovariation in machine parameters and tool materials. Welds were madeusing several tool materials, including polycrystalline cubic boron ni-tride and silicon nitride, and were evaluated by lap shear tension test-ing, micro-hardness and metallography. A significant difference inweld performance was documented based on variations in plungetechniques.

8:20 AMPrediction of Tool Temperature in Friction Stir Welding of 6061AluminumM. Miles*, T. Nelson, Brigham Young University, USA; L. Fourment, Ecole desMines de Paris - CEMEF, France

A finite element model of friction stir welding was developed in orderto predict tool temperatures during steady state welding conditions.

A series of experiments were also carried out in order to validate themodel. Thermocouple measurements were taken during welding ex-periments near the tip of the pin, near the base of the pin, and nearthe edge of the shoulder. For a feedrate of 3.4 mm/sec and a toolspeed of 650 rpm, tool temperatures reached approximately 485C atthe edge of the shoulder and 540C near the tip of the pin. However,the model predicted that the greatest temperatures occurred near theedge of the shoulder, with lower temperatures at the pin. Using aTresca friction law, and a friction factor of 0.4, the model predicted apin temperature of 500C and a shoulder temperature of 530C. Rea-sons for the discrepancy may be related to the amount of heat calcu-lated by the model based on plastic deformation versus friction.

8:40 AMMicrostructural Evolution in Friction Stir Welding of Titanium 6/4H. Rubisoff*, J. Querin, J. Schneider, Mississippi State University, USA

Flat panels of Ti-6Al-4V were friction stir welded (FSW) using varyingweld process parameters and pin tool geometries. The resulting weldswere characterized to determine the effect of the parameters on the qual-ity of the welds.Transverse cross sections of the welds were uniaxially ten-sile tested, then representative samples were metallographically mountedfor microstructural characterization. All tensile specimens failed withinthe weld nugget with an average ultimate strength of 104 ± 9 ksi or 70 ±2% of the parent material properties. The microstructure was character-ized using optical microscopy (OM), transmission electron microscopy(TEM) and x-ray diffraction (XRD). Effects of the varying conditions onthe resulting microstructure will be discussed in this manuscript.

9:00 AMFriction Stir Processing of Ti-5111M. J. Rubal*, J. C. Lippold, M. C. Juhas, The Ohio State University, USA

Microstructure evolution during friction stir processing (FSP) of Ti-5111 performed both above and below the β-transus temperature wasinvestigated. Each processed panel was instrumented with thermocou-ples to record the thermal histories experienced in the stir zone and ad-jacent heat-affected zone. The temperature profiles were analyzed usingsingle sensor differential thermal analysis (SS-DTA) which allowed de-termination of the β-transus. The FSP microstructures were character-ized using light and scanning electron microscopy. Based on these trials,hot torsion experiments were conducted using a Gleeble 3800 in orderto simulate the FSP microstructures. FSP above the β-transus resultedin extreme grain refinement – over a 200X reduction relative to the basemetal. The simulations were able to replicate the FSP microstructuresunder specific combinations of strain, strain rate and temperature. Mi-crostructure evolution during FSP of Ti-5111 was simulated using hottorsion experiments by controlling temperature, strain, and strain rate.

9:20 AMPin Tool Geometry Effects in Friction Stir Welding Ti 6-4J. Querin*, H. Rubisoff, J. Schneider, Mississippi State University, USA

Friction stir welding is a thermo-mechanical process that utilizes anon-consumable rotating pin tool to stir the edges of a weld seam to-gether. The pin tool is responsible for generating both the heat re-quired to soften the material and the forces necessary to stir and con-solidate the weld seam. As such, the geometry of the pin tool isimportant to the quality of the weld and the process parameters re-quired to produce the weld. Because the geometry of the pin tool islimitless, a reduced set of pin tools was formed to systematically studytheir effect on the weldment with respect to mechanical propertiesand material flow. In this study, 0°, 15°, 30°, 45°, and 60° tapered mi-crowave sintered tungsten carbide pin tools were used to weld Ti 6-4.Transverse sections of the weld were mounted, polished, and etchedfor optical microscopy (OM) analysis, while polished sections werealso analyzed using orientation image mapping (OIM) in the scan-ning electron microscope (SEM).

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 131

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania132

10:00 AMSucking-Extruding Theory for the Material Flowing along theThickness of the Plate during Friction Stir WeldingL. Xing*, L. Ke, S. Wang, F. Wang, Nanchang Hongkong Unversity, China

The influence of pin features on the material flow behavior in Fric-tion stir welds was investigated by using welding tools with screwedand smooth pin. It is shown that, the flow behavior of the weld mate-rial is influenced, obviously, by the surface features of the pin. If thereare threads on the pin surface, the material adjacent the pin will movedownwards or upwards and the material a little far from the pin willmove adversely. The primary driving force for the material flow is thepressure that the thread on the pin acts on its adjacent material whenthe pin is rotating, which makes the pin to function as a pump todraw the material flowing along the edge of the pin, and then to drivethe material move in circulation spatially. Based on these phenome-non’s, a new flow model, called sucking-extruding theory, is sug-gested, which can describe the flow phenomenon of the weld materi-als along the thick direction of the plate.

10:20 AMDiffusion Bonding of 316L Stainless Steel for ITER ApplicationsJ. Puskar*, S. H. Goods, Sandia National Laboratories, USA

The ITER experimental fusion reactor first wall structure designs cur-rently necessitate joining by diffusion bonding between beryllium, acopper alloy, and 316L stainless steel structures and tubing. The 316Ltube to base joints are particularly important given the pressure vesselcodes to which the structures must be manufactured. Samples, eachconsisting of two 316L cylinders were fabricated via direct Hot Isosta-tic Pressing (HIP). Additional samples employed metallic interlayersto promote bonding. Overall, HIP bonding temperatures ranged be-tween 940C to 1120C. In every instance, the processing time andpressure were held constant at 2 hours and 100 MPa. Bond strengthand ductility were measured using tensile specimens cut from thesamples while metallographic sections were used to evaluate the bondline microstructural changes. While ultimate strength of the bondedspecimens was similar to control specimens of the parent metal, largedifferences in the ductility were observed and will be discussed.

10:40 AMA New Method for Bond Strength Evaluation for LaminatedStructures Made by Ultrasonic BondingC. Zhang, A. Deceuster, L. Li*, Utah State University, USA

A push-pin test method for bond strength evaluation in the thicknessdirection for laminated structures has been developed. The methodhas been validated and successfully applied to ultrasonic consolida-tion (UC). Bond strength varying with UC process parameters hasbeen studied. Based on the results of simulation and experiment, ithas been proved that a strong quantitative correlation exists amongprocess parameter, plastic deformation, bonded area-ratio, and bondstrength. Plastic deformation is the major fundamental phenomenonon the ultrasonic bonding interface. Higher plastic deformation cor-responds to greater bond strength.

11:00 AMDiffusion Bonding of Steel and Magnesium Alloy Using Zinc InsertT. Tachibana*, S. Hojo, S. Iwatani, Graduate school of Engineering OsakaUniversity, Japan; S. Nakagawa, K. Miyamoto, NISSAN MOTOR CO.,LTD.,Japan; A. Hirose, Graduate school of Engineering Osaka University, Japan

The purpose of our study was to achieve highly reliable dissimilarbondings of steel/Mg alloy using zinc insert. We analyzed the inter-faces of joints using BSE, EDX and X-ray diffraction and performedtensile tests. To investigate the effect of Zn insert, we performed twokinds of dissimilar joinings of a Mg-3mass%Al alloy to Zn-coated(GI) and Zn-uncoated(SPCC) steels. In addition, to clarify theeffect of Al content in Mg alloy on the bondability, we also made Mg-6mass%Al/GI bondings. The Zn coating significantly improved the

bondability, which resulted from a Zn-Mg eutectic reaction effectivityremoving the oxide film on the Mg alloy at a low temperature. Thebonding in Mg-3mass%Al/GI joints achieved via a discontinuousand thin Fe-Al interfacial reaction layer. In Mg-6mass%Al/GI joints,the reaction layer formed continuously and composed of FeAl3 andAl3Mg2. The tensile strength of Mg-6mass%Al/GI joint was im-proved to be 70MPa from 40MPa in Mg-3mass%Al/GI joint.

11:20 AMFricRiveting: A New Joining Technique for Thermoplastic-Lightweight Alloy StructuresS. Amancio*, J. F. dos Santos, GKSS Research Centre, Germany

Polymer-metal structures frequently present joints due to problems asso-ciated with component size, fabrication capabilities and physical-chemi-cal material incompatibilities. Available joining methods for these struc-tures are usually application-specific, presenting disadvantages such ashigh operational costs, limited performance or are not environmentalfriendly. The FricRiveting technique is a new spot joining process devel-oped for thermoplastic-lightweight alloys joints, based on friction weld-ing and mechanical fastening. In the process, a cylindrical metallic rivet isused to join thermoplastic components by means of plasticizing and de-forming the tip of the rotating rivet through frictional heating in the jointarea. In this study, joints on polyetherimide and AA2024 aluminum alloywere evaluated. Sound joints with elevated tensile and shear strengths(60%-97% of base materials) were successfully produced within shortjoining cycles and with minimal preparation of joining partners.

11:40 AMElectromagnetic Pulse Bonding of Al/Cu JointsH. Bahmanpour*, Wayne State University, USA; J. Shang, Hirotec America,USA; X. Wu, Wayne State University, USA

In recent years electromagnetic pulse bonding has received an increasedinterest in material processing and manufacturing, due to its capabilityto join dissimilar materials. In this paper, electromagnetic pulse bond-ing of aluminum-copper tubes is studied, and the effect of applied pulseenergy and workpiece surface condition and geometry on the bondingstrength are reported. The produced wavy bi-material interfaces undervarious processing conditions were characterized by mechanical test-ing, and by microstructural and chemical analyses with optical mi-croscopy, SEM and TEM. It has been found that the mechanical mixingof two materials under high-energy pulse collision plays an importantrole in joint formation. Other bonding mechanisms involved in thebonding of Al/Cu, including the possibility of stress-assisted chemicalreaction in the formation of an intermetallic phase are also discussed.

Processing & Product Manufacturing:Paradigm Shift in the Metals Industry

Paradigm Shift in the Metals Industry IIIRoom: 411Session Chair: John Grubb, ATI Allegheny Ludlum

8:00 AMNew High Temperature and Corrosion Resisting Wrought Alloysfor Advanced Technologies of the 21st Century (Invited)D. Klarstrom, L. Flower*, Haynes International, Inc., USA

Since 1912, the Haynes organization has developed, manufactured,and distributed high temperature and corrosion resisting wroughtnickel and cobalt based alloys for high performance applications inaerospace, chemical, power, and other industries. As industrial tech-nology goes forward in the 21st century, advanced processes demandnew alloy solutions. In the current decade, Haynes International hasintroduced to the engineering community six new alloys invented inthe Haynes laboratories: HAYNES® 282®, NS-163®, and HR-224™ al-loys and HASTELLOY® G-35, C-22HS®, and HYBRID-BC1® alloys.Haynes research is ongoing to develop future new alloys that will keep

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 132

Tues

day

AM

www.matscitech.org 133

pace with technical progress in high performance industries andemerging technologies.

8:40 AMRecent Changes in the Titanium Industry (Invited)C. Moulton*, Uniti Titanium LLP, USA

Changes in the global titanium over the last 20 years will be describedand trends highlighted.

9:20 AMReactive Metals React to Global Changes (Invited)R. D. Goin*, ATI Wah Chang, USA

The past several years have seen significant changes in the metals in-dustry. In particular the growth of manufacturing in China and theshifting energy sector have driven many metals to all time high prices.This has been happening at the same time that China has also beenincreasing their internal production capabilities of raw metals andequipment fabrication. Reactive metals have not been immune fromthis trend. Traditional major applications of reactive metals such asthe chemical process industry (CPI) and nuclear power generationhave seen robust growth for the past few years after many years of de-cline. Furthermore, as the metals industry was reacting to this chang-ing environment, new applications for reactive metals developed,such as the use of hafnium in electronics.

10:00 AMRecent Advances in Refractory Metals (Invited)P. Kumar*, H.C. Starck Inc., USA

Conventional uses of refractory metals are based on their chemical,physical and electrical properties. These include, but not limited to, ca-pacitors, ballistics, furnace parts and chemical processing industries,super alloys, glass processing, super conducting applications, and thethermal management. Recently, a new application for refractory met-als has emerged. It is based on the inter-diffusion properties of copperand refractory metals. The application is diffusion barrier between sil-icon (and glass) and copper. Specific examples include integrated cir-cuits, flat panel displays and photovoltaic. This presentation will dis-cuss details of these applications, critical properties of refractorymetals to meet stringent technical requirements and further advance-ments in refractory metals research pertaining to these applications.

10:40 AMUtilizing Glass Forming Iron Based Overlays For Replacement ofHardmetals In High Wear ApplicationsD. J. Branagan*, A. R. Patete, B. E. Meacham, B. D. Merkle, W. D. Kiilunen,The Nanosteel Company, USA

In recent years, there has been an unprecedented rise in raw materialcosts. For high wear applications, hardmetals, generally based ontungsten carbide, have been the materials of choice but have becomeincreasingly expensive. While much lower cost, steel usage has beenlimited for these applications due to a big gap in wear performancebetween hardmetals and steels. A new approach to bridging this gapwill be presented utilizing glass forming steels. Refined microstruc-tures of the welded deposits leads to high hardness (Rc ≥70), wear re-sistance (≤ 0.10 g ASTM G-65) and significant toughness (Charpy ≥60 ft-lbs). The structure and properties of these deposits using arange of wire diameters and welding processes will be discussed. Theresulting wear resistance surfaces applied as overlay or wear plateoffer competitive advantages to existing high wear solutions in termsof attractive property combinations such as hardness, wear resistance,and toughness.

11:00 AMBlow forming characteristics of AZ31 alloy sheetsY. Kwon*, Y. Lee, J. Lee, Korea Institute of Materials Science, South Korea

In the present study, blow forming characteristics of AZ31 alloywere investigated in terms of grain size, temperature and forming

speed. A series of tensile tests were carried out to take the flow be-havior response in terms of grain size, temperature and strain rate.For all grain sizes, elongation increased with temperature incre-ment as well expected. However, the differences in grain size didnot give a larger elongation differences even at the temperaturerange where a large elongation would be expected with such as finegrains. Blow forming experiments gave similar results. However, ainteresting feature was that formability of AZ31 alloy showed dif-ferent trend with stress condition, which meant that biaxial stresscondition might result in lower temperature and strain rate de-pendencies compared to uniaxial tension results. Microstructurealong with texture observation has shown that grain boundarysliding seemed to be accommodated with slip as well as twinningactivity.

11:20 AMMicrowave and Conventional Sintering of Premixed andPrealloyed Tungsten Heavy AlloysA. Mondal*, Indian Institute of Technology Kanpur, India; D. Agrawal, ThePennsylvania State University, USA; A. Upadhyaya, Indian Institute ofTechnology Kanpur, India

Microwave sintering is fundamentally different from conventionalsintering. In the microwave sintering process, heat is generated inter-nally or volumetrically within the material instead of originatingfrom external heating source. Sintering cycle time for microwave sin-tering is exceptionally short of only 5-10 minutes as compared to 15-20 hours for conventional sintering cycles. The rapid heating rate ofmicrowave sintering greatly restricts tungsten grain coarsening,which resulted in fine tungsten grain distributed in Ni-Cu matrix.The aim of the present investigation is to study the sintering behaviorof premixed and prealloyed W-10 Ni-Cu (7:3) powders in both, a mi-crowave furnace as well as a conventional furnace. The comparativeanalysis is based on the sintered density, densification parameter,hardness and microstructures of the samples. The present investiga-tion also includes the variation of matrix composition as a functionof temperature by EPMA analysis.

11:40 AMThermal Transfer Across Steel Copper Interface in RSP BimetallicToolingJ. Knirsch*, RSP Tooling, LLC, USA

The RSP Bimetallic Tool of steel copper is used where the heat transfercapability of copper is required but the process requires steel to main-tain die life. Since the interface between the steel and copper is physicalthere was concern that heat will not transfer across the interface rapidlyenough to benefit the process. Tests were run both in the lab and in pro-duction to prove that the bimetallic tool would indeed decrease cycletime through increased heat transfer. Results indicated that the inter-face did not have a negative effect on heat transfer and cycle times couldbe improved as much as 35% when compared to solid steel tooling.

Processing & Product Manufacturing:Processing, Properties and Performance ofComposite Materials

Aluminum Matrix Composites Room: 412Session Chairs: Benjamin Schultz, University of Wisconsin-Milwaukee; Darrell Herling, Pacific Northwest National Lab

8:00 AMCryomilled Aluminum Alloy and Boron Carbide Composite PlatesR. Vogt*, Z. Zhang, T. D. Topping, E. J. Lavernia, J. M. Schoenung, UCDavis, USA

The addition of ceramic particulate reinforcement during cry-omilling has been shown to significantly increase the strength of Al

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 133

Tuesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania134

alloys. In the present study, boron carbide (B4C) was cryomilled withAl 5083 to form an ultra-fine grained (UFG) metal matrix powder.This powder was blended with un-milled Al 5083 to increase ductilityand consolidated by three different methods to form large, bulk, UFGcomposite plates. The processing effects of hot isostatic pressing(HIP) and forging conditions have been investigated on the basis ofresulting microstructure, mechanical behavior and fracture surfacesof the final consolidated plates.

8:20 AMThermal Stability in Ultrafine-Grained Al 5083 after Cryomillingand ConsolidationT. D. Topping*, Y. Li, R. G. Vogt, Z. Zhang, J. M. Schoenung, E. J. Lavernia,University of California, Davis, USA

Aluminum alloys with nanocrystalline (NC) and ultra-fine grain(UFG) size are of strong interest because of their high strength – typ-ically over 30% stronger than conventionally processed alloys of thesame composition. Because of the high driving force for grain growthin UFG materials, however, thermal stability can be a concern. Forthis study, the microstructure and mechanical behavior of UFG Al5083 plate, produced by quasi-isostatic (QI) forging of cryomilledpowder, has been investigated and compared to conventional, coarse-grained Al 5083 - in particular, the ability to retain strength after hightemperature annealing over a range of times from 10 minutes to 24hours. Mechanical tests reveal the retention of high strength and rea-sonable ductility in the UFG Al 5083 after cryomilling in liquid nitro-gen and subsequent QI consolidation. Microstructural analysis cor-roborates the test data by showing limited grain growth, via Zenerpinning, regardless of annealing time.

8:40 AMDevelopment of an Alternative Aluminum Matrix Composite forBearing ApplicationsR. Carrasquillo*, T. K. Adelakin, O. M. Suárez, University of Puerto Rico, USA

To improve wear resistance, aluminum-boron alloys are reinforcedwith tin, and the mechanical properties of the resulting mix are com-pared to those of existing Al-Si-Sn alloys. The study analyzes: the ef-fect of chemical composition (Sn, and B or Si levels); the effect ofcasting processing (gravity and centrifugal casting) and the interac-tion between B or Si levels with casting parameters. The responsevariables selected are related to the expected final application of theproposed alternative material: hard particle distribution (quantitativemetallography), bulk and micromechanical strength of the materials(differential thermomechanical analysis, microhardness and surfacehardness), wear response such as wear track produced by a pin-on-disk apparatus (optical, electron, and atomic force microscopy), andphases thermal stability (high temperature X-ray diffraction and dif-ferential thermal analysis). Preliminary results indicate greater hard-ness and particle distribution in boron alloys.

9:00 AMMechanical Properties of Hybrid Composite Extrusions of anAluminium-Alumina wire reinforced Aluminium AlloyM. J. Merzkirch*, University Karlsruhe, Germany; D. Pietzka, TechnicalUniversity Dortmund, Germany; K. Weidenmann, E. Kerscher, D. Löhe,University Karlsruhe, Germany

The aim of the present work, considering the main purpose of light-weight structures, is to increase the specific strength and stiffness byusing alumina-aluminium composite wire reinforced aluminiumalloy instead of common bulk metal wire. The compound extrusionprocess allows a direct embedding of the composite wire into an alu-minium alloy to produce continuously reinforced extrusions forstructural applications. In order to characterise the efficiency of thehybrid composite and to compare the properties to spring steel rein-forced aluminium alloy, the debonding shear strength and quasistaticproperties have been investigated. Additionally metallographic analy-ses show that the composite wire is well embedded into the matrix. In

summary, it is shown that hybrid extrusions are promising solutionsfor lightweight profiles but to achieve better mechanical the materialssystem for the composite wire has to be improved.

9:20 AMUltrasonic Consolidation of Pure Al and Composite Al-Ni PowderCompactsD. Colanto*, D. Erdeniz, G. Gulsoy, Northeastern University, USA; I. E.Gunduz, University of Cyprus, Cyprus; T. Ando, Northeastern University,USA; P. Y. Wong, Tufts University, USA; H. Doumanidis, University ofCyprus, Cyprus

A novel ultrasonic powder consolidation technique was employed toproduce monolithic Al and composite Al/Ni compacts (0.5 mm thick,3.5 mm in diameter) from elemental powders. Al specimens wereprepared systematically at temperatures up to 573K and pressures upto 200 MPa, while keeping the vibration frequency, duration, and am-plitude fixed at 20 kHz, 1 s, and 14 μm, respectively. Examination byscanning electron microscopy showed that full-density, oxide-freeconsolidation in air is possible. Full density-consolidated Al speci-mens withstood 180° bending at room temperature. Al-Ni speci-mens, fabricated under similar conditions, were also fully dense ex-hibiting a composite microstructure of Ni particles uniformlydistributed in an Al matrix. Differences in microstructure and ductil-ity are discussed with respect to processing conditions.

10:00 AMChemical composition effects on the microstructure offunctionally-graded aluminum matrix compositesL. Olaya-Luengas*, O. Suárez, University of Puerto Rico, USA

Aluminum matrix composites reinforced with diborides can be trans-formed in functionally graded materials via centrifugal casting. The re-distribution of the denser dispersoids in the aluminum matrix is furtheraffected by changes by the levels of boron, magnesium, copper, zirco-nium and vanadium. The present research focused on the functionalizedcomposite microstructure and the resulting graded mechanical proper-ties. The final goal has been to determine the optimal reinforcement dis-tribution as a function of the chemical composition of the material.

10:20 AMDevelopment of Particulate Reinforced Aluminium Metal MatrixCompositeD. E. Esezobor, S. A. Balogun, S. O. Adeosun*, A. M. Oladoye, L. O. Osoba, C.U. Kuforiji, University of Lagos, Nigeria

The mechanism controlling the strength of Al-SiC particulate com-posite produced by liquid metallurgy route is being investigated. Theeffect of particle size, volume fraction and other processing parame-ters is studied alongside with the development of microstructuressuitable for super plasticity in aluminium alloy based MMC. Alu-minum silicon composite were produced in 95%Al-5%SiC, 90%Al-10%SiC,80%Al-20%SiC, and 70%Al-30%SiC ratios with an averagegrain size of 240μm, 480μm, 840μm,and 4200μm respectively via liq-uid metallurgy route. The result revealed that increasing volume frac-tion and decreasing particle size of the particulate had significant ef-fect on the mechanical properties this is explained via the evolvingmicrostructure.

10:40 AMCarbon Fibre Reinforced Aluminum Matrix Composite:Development & Evaluation of Mechanical BehaviorsA. Edacherian, J. M. Antony*, National Institute of Technology Calicut, India

Lightweight materials have gained major importance in most manu-facturing sectors such as aviation industry. Extensive research in aug-menting strength vis – a - vis mechanical properties of these materialshave resulted in the development of fibre reinforced metal matrixcomposites. This paper presents a systematic design and synthesisprocedure for development of composite using aluminium alloy andcarbon preforms through Squeeze infiltration process. Optical mi-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 134

Tues

day

PM

www.matscitech.org 135

croscopy on the specimens prepared from the cast composite andSEM fractography studies reveals proper infiltration, better distribu-tion of fibers in matrix and an increased diffusion bonding betweenfibre and matrix under optimal operating conditions. Brinell Hard-ness of the composite was compared with that of aluminium alloyprocessed through squeeze casting and gravity die casting. Thetoughness of the composite measured using Charpy Test and com-pared with squeeze cast specimens indicates four fold improvement.

11:00 AMCompression Tests on Powder Sintering Fabricated Al MatrixSyntactic FoamsX. Tao*, Y. Zhao, L. Zhang, University of Liverpool, United Kingdom

Metallic syntactic foam consists of hollow spheres embedded in a con-tinuous metal matrix have good energy absorption. The existing fabri-cation of infiltration techniques have limitation of immovable volumefraction of metal matrix. Therefore powder sintering technique is used.Al matrix syntactic foam samples were made by powder sintering usingAl alloy 6063, with avarege size of 53μm and three size ranges of prousceramic micro spheres(CMS),75-125 μm,125-250μm and 250-500μm,respectively. The volume fraction of the matrix varying from 40%to 70%. Static compression tests were carried out on fabricated sam-ples. The 250-500μm CMS type samples displayed relative high com-pressive strength than that of the other two types foams. This indicatesin the fabrication of metallic syntactic foams using powdering sinter-ing method, size ratios between the metal powder and the embeddedspheres can affect the mechanial property of the fabriabed foams.

11:20 AMMechanical properties of Al/Al-Cu-Fe compositesS. Dubois*, G. Laplanche, T. El-Kabir, V. Gauthier-Brunet, A. Joulain, J.Bonneville, Laboratoire PHYMAT, France

In this study, Al/Al-Cu-Fe composite materials are produced usinghot isostatic pressing technique. Depending on the processing tem-perature (Tp), the reinforcement particles were of the i-phase (Tp =673K) or of the omega-phase (Tp = 823K). Compression tests wereperformed at constant strain-rate in the temperature range 293K-773K. These tests were supplemented by stress relaxation experi-ments to evaluate the strain rate sensitivity of the stress. For bothcomposites, the flow stress is strongly temperature dependent and ex-hibits two temperature regimes, suggesting that thermally activatedprocesses control plastic flow. The temperature regimes are con-firmed by the strain-rate sensitivity of the stress. In the low tempera-ture regime, the yield stress values of Al/omega-Al-Cu-Fe compositeare about 50% higher than the one of the Al/i-Al-Cu-Fe composite. Adetailed comparison of the mechanical properties of both compos-ites will be presented and discussed in terms of possible operatingmechanisms.

Special Topics: Industry Track 2008

Industry Track 2008, Tuesday PMRoom: Hall A

2:00 PMManufacturing at the Right Size for the Emerging SOFC Market(Invited)J. Foreman*, Fuelcellmaterials, USA

Stack developers are taking multiple paths to improve performanceand longevity, each with different materials sets, fabrication condi-tions and intended operating conditions. Many developers seek“standard” or “commodity” products under the premise that theymight better meet future needs even though large scale productionisn’t flexible to meet the requirements that are changing during SOFCdevelopment. Furthermore, in this phase only small quantities areneeded – 30-100 kg per megawatt for each non-support material. Thekey to both these issues is to have fabrications methods scaled to meet

the request with both cost-effectiveness and products representativeof future orders. Exacting control of standard and scalable equipmentmeans that processes developed in the lab are immediately transfer-able to multi-MW-sized equipment. This approach enables tailoringof products to meet the required processing and performance behav-iors when “standard” products cannot. We will demonstrate severalexamples of custom product development efforts to underscore theimportance of this methodology.

2:30 PMIndustry Track talk 2 (Invited)J. Dorr*, Nanocomp Technologies, Inc., USA

Abstract Not Available

3:00 PMCorning Incorporated - DuraTrap® AT Diesel Particulate Filter(Invited)D. Tennent*, Corning Incorporated, USA

Corning leveraged 50 years of ceramics research to create the CorningDuraTrap® AT particulate filter for diesel applications. We appliedour materials and manufacturing expertise to develop the AT filterusing a unique aluminum titanate composition that offers durabilityand excellent performance. The AT filter meets light-duty and heavy-duty life of vehicle regulations requirements. Corning’s presentationwill focus on how we met the final product and performance require-ments and how pore structure impacts functionality.

3:30 PMSubmicron Grinding with a Vertical Bead Mill (Invited)H. Way*, NETZSCH Fine Particle Technology, USA

Horizontal bead mills have been used for a number of years in appli-cations ranging from deagglomerating and dispersing tableware andsanitaryware glazes to grinding silicon carbide and other technical ce-ramics. However, some demanding processes exist where the abrasiveand corrosive natures of the slurry are not ideally suited for a horizon-tal mill. NETZSCH engineers designed a new mill to address the prob-lems of wear of the mechanical seal, simplification of the addition ofgrinding media (SiC grains) and inclusion of wear-resistant mill con-struction materials. Harry Way, technical director, NETZSCH FineParticle Technology, will address the issues of grinding with horizontalbead mills, and the advantages of working with a Vertical Mill System.

Special Topics: SBIR Program; Developmentof Innovative Materials Technologies forMilitary Systems

Development of Innovative Materials Technologiesfor Military SystemsRoom: 402Session Chair: Barry Cole, Barry Cole Training and Technologies, LLC

2:00 PMDefense Logistics Agency (DLA) Small Business InnovationResearch Program (SBIR)D. Gearing*, Defense Logistics Agency, USA

This presentation, by DLA’s SBIR Program Manager, will describehow DLA started its SBIR program in 2007 with an annual budget of$2.5M, focused on a single topic, “Advanced Technologies for Dis-crete-Parts Manufacturing” which will continue in 2008 and 2009.Several materials-related Phase I projects were awarded in 2007. Thepresentation will provide background information on DLA and alsodescribe why DLA prefers market – driven companies which canmove technology into the commercial high-volume market. Finally,the presentation will tell where DLA proposal evaluators are comingfrom, when they apply selection criteria to a particular proposal.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 135

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania136

2:20 PMGraphite Composite Tooling made from INVAR Using the RSPTechnologyJ. Knirsch*, RSP Tooling, LLC, USA

The Coefficient of Thermal Expansion(CTE) of the tool material is criti-cal to the production of graphite composite tooling. The RSP Toolingprocess can make tools significantly faster and for less money than stan-dard practices but the effect the rapid solidification process would haveon the CTE of INVAR was unknown. The RSP process has always im-proved the significant properties of the metals sprayed but these proper-ties are usually hardness,Yield strength,and Ultimate strength. No meas-urements of CTE had been recorded. Scrap INVAr was melted andsprayed in a test mold. Measurements were taken to determine CTE, den-sity, and other significant properties. The results as anticipated showedthat in all tests the material was equal or better than standard INVAR.

2:40 PMDevelopment of IR Transparent Polycrystalline Ceramics for DoDApplicationsM. R. Pascucci*, CeraNova Corporation, USA

CeraNova Corporation has been developing IR transparent polycrys-talline ceramics with funding from various DoD agencies through theSBIR program. In addition to several Phase I and Phase II programs,CeraNova has recently received enhancement and continued devel-opment funding to focus efforts towards transitioning the technologyto meet specific system requirements. CeraNova is also participatingin a DARPA funded consortium program as a subcontractor to a largegovernment contractor. A brief review of CeraNova’s technology willbe presented along with an overview of the company’s successful par-ticipation in the SBIR program.

3:00 PMDeveloping a Multi-Use Manufacturing Manipulator System(MUMMS) under NAVSEA SBIR Phase I and Phase IIJ. D. Wentz*, Temple Allen Industries, USA

This presentation, by GreyPilgrim’s Founder and CEO, will describehow GreyPilgrim participated in the NAVSEA SBIR Phase I andPhase II programs in 2000-2002 focused on developing a “A Multi-Use Manufacturing Manipulator System (MUMMS)” based on ourexisting EMMA manipulator system, which had been demonstratedand developed for use in nuclear remediation operations with sup-port from Lockheed Martin Hanford, Westinghouse Hanford, andNIST. The presentation will provide background information onGreyPilgrim and its successor company Temple Allen Industries anddiscuss how SBIR funding helped the technology progress to thepoint where it is established in the commercial market.

Electronic & Magnetic Materials:Electroceramics Technologies: The Past andFuture - A Celebration of the 50thAnniversary of the ACerS ElectronicsDivision

Electroceramic Technologies: Advances in Dielectricand Magnetoelectric MaterialsRoom: 315Session Chair: Paul Clem, Sandia National Laboratories

2:00 PMAn overview of ME laminates and devices (Invited)J. Zhai*, Z. Xing, Virginia Tech, USA; S. Dong, Peking University, China; J. Li,D. Viehland, Virginia Tech, USA

Since the turn of the millennium, giant magnetoelectric (ME) effectshave been found in laminated composites of piezoelectric and mag-

netostrictive layers. Compared to ME single phase and two phase par-ticulate composites, laminated composites have much higher ME co-efficients and are also readily fabricated. Here, we will first discusssome of the important advancements that have allowed for dramaticenhancements in the ME voltage and charge coefficients that includ-ing: (i) material couples, how the materials properties affect the lami-nate composites properties. (ii) laminate configurations and opera-tional modes, how the structure enhance the ME effect. Then we willshow new devices such as magnetic sensor, gyrator, transformer thatare based on ME effect.

2:40 PMA Review of the Multilayer Ceramic Capacitor: Past, Present, andFuture (Invited)C. Randall*, The Pennsylvania State University, USA

This presentation reflects the journey of the multilayer ceramic tech-nology that has been applied to multilayer capacitors. We will reviewthe early days of capacitors, consider the technology trends inregardto capacitance volumetric efficiency, and the different types ofprocesses that have been applied to developments in the field. We willdiscuss air-fired vs. base metal fired systems. We will review technicalchallenges with both of these types of technology and assess the ad-vantages and disadvantages of each type of technology. Finally, wewill review the immediate future trends and speculate on more futur-istic capacitor needs.

3:20 PMDielctric Properties of BaTiO3 Doped with Er2O3, Yb2O3 Basedon Intergranular Contacts ModelV. V. Mitic*, Faculty of Electronic Engineering, University of Nis, Serbia; V. B.Pavlovic, Faculty of Agriculture, University of Belgrade, Serbia; V. Paunovic,M. Dragan, P. Petkovic, Z. Ljiljana, Faculty of Electronic Engineering,University of Nis, Serbia

In this study, the model of intergranular impedance is establishedusing the equivalent electrical scheme characterized by correspon-ding frequency characteristic. Globally, BaTiO3 sample is consisted ofa huge number of mutually contacted grains which form clusters. Foreach of them, it is possible to establish the equivalent electrical modeland, for defined set of input parameters, using symbolic analysis, ob-tain the frequency diagram. Realizing the totality of relations be-tween clusters grains groups, their microelectrical schemes and cor-responding frequency characteristics, and equivalent electricalscheme and corresponding acquired frequency characteristics ofBaTiO3-ceramics samples, we set a goal of coinciding experimentalresults with the summing effect of microelectric equivalent schemes.The model is successfully tested on barium titanate ceramics dopedwith Er2O3, Yb2O3.

Electroceramic Technologies: Microwave Dielectricsand Sensor MaterialsRoom: 315Session Chair: Robert Schwartz, Missouri University of Science andTechnology

3:40 PMPreparation of low-loss titanium dioxide for microwaveapplicationsL. Zhang*, K. Shqau, G. Mumcu, K. Sertel, J. L. Volakis, H. Verweij, The OhioState University, USA

Dense titanium dioxide (TiO2) ceramics with unprecedented low mi-crowave losses were prepared, starting from commercially availablehigh-purity powders. The powders were deagglomerated and col-loidally stabilized in aqueous NH3 solution to form a stable suspen-sion. The suspension was screened, followed by colloidal-filtration,drying and sintering. A >99.5% density and ~2μm grain size wereobtained after sintering at 1000°C for 10 hours. The dielectric loss of

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 136

Tues

day

PM

www.matscitech.org 137

the dense-sintered TiO2 was tan(δ) = 1.4×10-4 at 6.4GHz at roomtemperature. These favorable results are attributed to a homogeneousmicrostructure. The process as described will enable new miniatureantenna concepts that rely on the availability of materials with a highdielectric constant and extremely low dielectric loss.

4:00 PMNanoparticle and Nanostructured Metal Oxide Arrays for GasSensor ApplicationsP. A. Morris*, E. Beach, A. Mark, Ohio State University, USA

The objective of this work is to develop a sensor array platform usingnanoparticle and nanostructured metal oxides for detecting the gasesof interest for environmental, defense and homeland security appli-cations. We are producing single crystal nanoparticles in the sizerange of 10 – 40 nm diameter of a variety of metal oxides using asolvo-thermal technique. Based on this success, we are now workingto deposit the metal oxides onto Si micro-hotplates so that the elec-tronics can be integrated into the sensor. The size and power require-ments of the sensors would allow them to be used as personal devicesor distributed geographically and probed remotely either individuallyor in a network. In this presentation, the results of nanoparticle andnanostructured sensor arrays will be shown in comparison to thosemade using micron-sized particles. Results indicate that significantimprovements can be made using the nanostructured materials inthe array.

Electronic & Magnetic Materials:Ferroelectrics and Multiferroics

Multiferroics and Magnetoelectric CompositesRoom: 318Session Chairs: Shashank Priya, Virginia Tech; Chong-Lin Chen,University of Texas, Austin

2:00 PMMultiferroic Behavior of Bi0.9-xLa0.1ErxFeO3 CeramicsP. Pandit*, S. Satpathy, P. K. Gupta, RRCAT, India

The objective of the current work was to prepare a simultaneouslyferroelectric and ferromagnetic compound at room temperature ex-hibiting magnetoelectric coupling. For this purpose, Er substitutedBiFeO3 particles Bi0.9-xLa0.1ErxFeO3(x=0.05, 0.07, 0.1) were pre-pared by conventional solid solution route. Backscattered SEM,X- raydiffraction,DTA studies and typical absorption peaks in the IR spec-trum confirmed the predominantly single phase characteristics ofBi0.9-xLa0.1ErxFeO3 ceramics. A structural phase transition fromrhombohedral phase to orthorhombic phase is indicated forBi0.8La0.1Er0.1FeO3. Significant change in both Curie and Neel’stemperature is observed on Er doping.The spin lattice coupling hasbeen manifested through dielectric anomaly at magnetic transitiontemperature.Multiferroic measurements showed field induced ferro-magnetism (remanent magnetization 0.1178 emu /gm forBi0.83La0.1Er0.07FeO3) and ferroelectricity (Pr = 1.4 -0.5 μC/cm2μC/cm2) at room temperature.

2:20 PMPhase field modeling of multiferroic compositesY. Ni*, A. Khachaturyan, Rutgers University, USA

A general 3-dimensional phase field theory is proposed to investigatethe strain-induced magnetoelectric effect in magnetoelectric com-posites. Based on the variation principle, we proved that the physicalfields of the heterogeneous magnetoelectric composites consisting ofthe coupling magneto-electric-mechanical response can be evaluatedby establishing an equivalent homogeneous system with the propereffective eigenstrain, polarization and magnetization, which are ob-tained by solving the time-dependent Ginzburg-Landau equations.

Some numerical examples demonstrated the advantage of this theoryto predicting the local and overall response of the magnetoelectriccomposites with arbitrary configuration under applied fields, and tooptimizing the composite architecture to pursue the strongest mag-netoelectric effect.

2:40 PMThe Effect of Particle Size on Magnetic Properties in MultiferroicYMn2O5 PowdersC. Ma*, J. Yan, R. McCallum, X. Tan, Ames Laboratory, U.S. DOE, USA

We have investigated the effect of particle size on the magneticproperties of YMn2O5 nanoparticles. Single phase YMn2O5nanoparticles were prepared by calcining the precursor powdersmade by a modified Pechini’s method under 10 bar O2. Powderswith different particle sizes were achieved by varying the calcina-tion temperature from 800°C to 1000°C. The particle size was de-termined by x-ray diffraction and transmission electron mi-croscopy. The magnetization studies revealed that the YMn2O5powders began to display particle-size-dependent properties whenthe particles were smaller than 160nm. With the decrease of theparticle size, a magnetic phase with a broad transition emerged at~40K and the transition became increasingly broadened. The hys-teresis loops of all the samples saturated at ~2000 Oe at 5K. Themagnetization at each field increased with decreasing the particlesize. The mechanism for this particle-size-dependent effect wasdiscussed.

3:00 PMNew Aspects of Magnetic and Dielectric Behavior of MultiferroicRMn2O5 (Invited)Y. Noda*, Tohoku University, Japan

Recent discoveries of the colossal magnetoelectric effect (CME) inTbMnO3 by Kimura and DyMn2O5 by Hur gave new stage on thestudy of multiferroics. They discovered that electrical polarization isflopped or flipped by magnetic field. Thus, we may control the fer-roelectric state not only by electric field but also by magnetic field.Polarization flop by magnetic field and polarization flip by electricalfield give four-state of the system, which can be used as memory de-vice, and this situation will presumably open new era for applica-tion. In my talk, I will show recent progress on the studies of mag-netic and ferroelectric properties of RMn2O5. When we measure thedielectric and magnetic structure in the H-T phase diagram, we caneasily say that the origin of the CME is the phase transition phe-nomena induced by magnetic field. The same phenomenon was alsoobserved against hydrostatic pressure. I will show new results inwhich ferrielectric character and polarization flop were found in thissystem.

3:40 PMMultilayer Magnetoelectric Nanostructures of CoFe2O4 – BaTiO3C. Park*, Virginia Tech, USA; H. Kim, University of Texas at Arlington, USA;R. Mahajan, S. Priya, Virginia Tech, USA

This paper reports the synthesis of multilayer magnetoelectric (ME)nanostructures in CoFe2O4 –BaTiO3 system. In past, bulk sinteredlaminates structures have been shown to exhibit higher ME responseas compared to other 3-dimensional composite geometries. The re-sponse depends on mainly two parameters (i) elastic strain fields,and (ii) interdiffusion of ions. Both these parameters can be maxi-mized by synthesizing a suitable interface structure in multilayergeometry. The composite thin films were synthesized by sol-gelprocess and spin coating techniques on silicon and SrTiO3 substrate.Various tools were used to characterize the structure of the films in-cluding XRD, HRSEM, TEM, and PFM. Electrical and magneticproperties of the samples was characterized to correlate with thestructure.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 137

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania138

4:00 PMSynthesis of Layered Magnetoelectric Composites through“Bottom-Up” ApproachR. Islam*, N. Podual, J. P. Liu, C. Kim, University of Texas at Arlington, USA;S. Priya, Virginia Tech, USA

In this study, we first investigated the synthesis and characterizationof a core-shell pattern of Pb(Zr0.52,Ti0.48)O3 (PZT) and NiFe2O4(NFO), where PZT is core and nanosize NF is shell. PZT was synthe-sized using conventional ceramic processing route while nanosize (~20 – 30 nm) NFO particles were synthesized using standard airlesschemical synthesis technique in a nitrogen atmosphere. Ni(acac)2and Fe(CO)5 precursors solutions were used for the chemical synthe-sis. Characterization of PZT (structural) and NFO particles (struc-tural and magnetic) was done using x-ray diffractometer and alter-nating gradient magnetometer. TEM investigations showed that theNFO nano particles coating on top of PZT particles was about 2-3layers. Secondly, using this core – shell particles, a bulk laminatedcomposite was synthesized in an epoxy matrix by spin coating. Mag-netic and magnetoelectric characterization of these composites isunder progress and will be reported at the meeting.

Electronic & Magnetic Materials: Interfacesand Defects in Functional Oxides

Characterization of Functional OxidesRoom: 319Session Chairs: Judith Yang, University of Pittsburgh; GuangwenZhou, State University of New York, Binghamton

2:00 PMNanometer-Scale Structural Order in Amorphous OxidesMeasured with Fluctuation Electron Microscopy (Invited)P. Voyles*, W. Stratton, University of Wisconsin, Madison, USA; M. Kisa, J.Yang, University of Pittsburgh, USA

Structural order in amorphous materials at the nanometer scale canbe difficult to measure with conventional structural probes like x-rayor neutron diffraction. Fluctuation electron microscopy (FEM), atechnique which uses electron nanodiffraction to measure spatialfluctuations in the diffracted intensity, is sensitive to order at thislength scale: large fluctuations in intensity mean a heterogeneousstructure with some order, while small fluctuations mean a homoge-neous, disordered structure. We have used FEM to show that aggres-sive oxidation with hyperthermal atomic oxygen creates amorphousSiO2 and Al2O3 with strong signatures of crystal-like order not foundafter oxidation with molecular oxygen, and that HfO2 deposited byatomic layer deposition which appears amorphous to x-ray diffrac-tion is very strongly ordered at the nanoscale. In both cases, the struc-tural order of the amorphous materials can influence their propertiesand crystallization behavior.

2:40 PMStructural Characterization of Functional Oxides (Invited)Y. Zhu*, BNL, USA

Electron microscopy is playing an increasingly important role instructural characterization due to the strong interaction of electronswith matter and the high spatial resolution of an electron probe pro-vides to reveal local structural inhomogeneity and defects that con-trol the properties of functional materials. In this talk, we will presentour recent work on various functional oxides including high-temper-ature superconductors, dielectric and thermoelectric compounds,and materials that exhibit colossal magneto-resistance effects. Variouselectron microscopy based techniques such as high resolution imag-ing (TEM/STEM), electron diffraction, electron energy-loss spec-troscopy and electron holography are employed to understand theexotic physical behavior of the oxides. Experiment observations are

compared with theoretical calculations. Supported by U.S. DOEunder contract No. DE-AC02-98CH10886. Collaborations with L.Wu, J. He, P. Oleynikov, and V.Volkov, M. Schofield, C. Johnson andJ.C. Zheng are acknowledged.

3:20 PMHRTEM and Diffraction Analysis of Surface Phases inNanostructured LiMn1.5Ni0.5O4 SpinelF. Cosandey*, N. Marandian-Hagh, G. G. Amatucci, Rutgers University, USA

The Ni doped transition metal spinel LiMn1.5Ni0.5O4 (Spacegroup Fd-3m) is an excellent candidate as Li-ion cathode materialfor high voltage applications due to its high capacity (> 130 mAh/g).In order to improve its performance at high temperatures (60 oC),we have introduced a surface modification process involving treat-ments in hydrofluoric (H-treated) or phosphoric (P-treated) acidsfollowed by high temperature annealing.. In this paper, we presentHRTEM, nano-probe diffraction and image simulation results onthe formation of a surface phase induced by these surface acidic andannealing treatments. The surface modified LiMn1.5Ni0.5O4 spinelshows extra superlattice reflections with (110), (210), (310) type re-flections which have been attributed to the ordered P4332 spinel.HRTEM images and dynamical image simulations are consistentwith diffraction results and confirm the formation of distinct sur-face phase.

3:40 PMStrain Relaxation Mechanisms of (Ba,Sr)TiO3 Films Grown on[001]- and [111]-Oriented Perovskite SubstratesH. Du*, S. Wang, T. N. Nuhfer, P. A. Salvador, M. Skowronski, CarnegieMellon University, USA

Strain strongly affects the properties of (Ba,Sr)TiO3 films as thefunctional material in microwave communication or data storagedevices. While previous work has focused on determining themechanisms of strain relaxation for (100)-oriented films on per-ovskite substrates, conflicting mechanisms exist. We focused onstudying the epitaxial strain relaxation of Ba0.6Sr0.4TiO3 filmsgrown with pulsed laser deposition on both SrTiO3(111) and (100)substrates. Using plan-view and cross-sectional transmission elec-tron microscopy, misfit dislocations in the (111) films were ob-served to form a triangular network with dislocation lines in <11-2> directions and Burgers vectors of a<1-10> type. Ourobservations were consistent with relaxation occurring via disloca-tion climb described by the slip system <110>{1-10}. Revisiting therelaxation mechanism of (100) films, our microscopy observationswere consistent with relaxation via dislocation glide on the<110>{1-10} slip system.

4:00 PMEnhancing Insulation for BaTiO3-Based Sub-micron CapacitorLayersR. D. Levi*, S. Trolier-McKinstry, C. A. Randall, Penn State, USA

The temperature dependence of the electrical leakage current den-sity of chemical solution deposited BaTiO3 films on Ni foils was in-vestigated as function of the underlying Ni microstructure. Theelectrical properties were characterized on capacitors with andwithout the presence of Ni grain boundaries. When a Ni grainboundary from the substrate is present in the capacitor ,it is foundthat the loss tangent of the capacitor rises rapidly at low fields. Thecritical bias substantially increases when no substrate grain bound-aries are present. This disparity in the electrical behavior was ana-lyzed in terms of the mechanisms of charge conduction across theNi-dielectric interface. While a reverse biased Schottky emissionmechanism dominates the current in areas free of Ni grain bound-aries, the barrier at the cathode is ineffective when Ni grain bound-aries are present in the substrate. This, in turn, leads to a larger

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 138

Tues

day

PM

www.matscitech.org 139

leakage current dominated by the forward biased Schottky barrierat the anode.

Electronic & Magnetic Materials:International Symposium on AdvancedDielectric Materials & Electronic Devices

Synthesis and Properties IRoom: 317Session Chair: Ruyan Guo, University of Texas at San Antonio

2:00 PMMicrowave Processing of Dielectrics for High Power MicrowaveApplications (Invited)I. K. Lloyd*, Y. Carmel, University of Maryland, USA; O. C. Wilson, CatholicUniversity of American, USA

While most electronic applications are moving rapidly towards solid-state devices, high power microwave communication devices still uti-lize vacuum tube technology to achieve the required power density.Traditionally BeO and BeO composites were used as support and tun-ing dielectrics. However, AlN based materials are now desirable dueto the health effects of BeO. Dielectric constant and thermal conduc-tivity are the key properties for high power communications. Evenwith liquid phase sintering it is not easy to achieve high thermal con-ductivity in AlN materials using conventional firing. Microwave fir-ing promotes rapid development of thermal conductivity. With mi-crowave firing, thermal conductivities above 200 W/mK in pure AlNcan be achieved in four hours. In addition, thermal conductivities of100-150 W/mK can be achieved in tailored dielectric constant AlN-TiB2 and AlN-SiC tuning dielectric composites in 1-2 hours. Our ap-proach is applicable to other applications for AlN and its composites.

2:20 PMCombined Dilatometry and Mass Spectrometry in the Sintering ofPerovskite Ceramic MaterialsS. J. Lombardo, M. Schurwanz*, University of Missouri, USA

A combined dilatometer-mass spectrometer system (CDMS) hasbeen developed to examine the high temperature chemistry thataccompanies the sintering process. In the sintering of perovskitematerials such as strontium titanate, the evolution of species in thegas-phase may influence sintering kinetics, defect equilibria, elec-trical properties, and sample homogeneity. In this paper, we de-scribe the development of a combined dilatometer-mass spec-trometer system (CDMS) to examine the high temperaturechemistry that accompanies sintering. We specifically examinesome different designs pertaining to the gas coupling unit betweenthe two devices. We also present some preliminary data relating theevolution of species in the gas phase and the redox chemistry ofstrontium titanate.

2:40 PMComplex impedance analysis of fine grain and coarse grain TiO2ceramicsS. Chao*, V. Petrovsky, F. Dogan, Missouri University of Science andTechnology, USA

TiO2 ceramics with a grain size ranging from 100nm to 1000nm wassynthesized and studied by complex impedance technique fromroom temperature to 550oC in the frequency range 1 to 1MHz. Elec-tric modulus representation clearly shows that there is only one re-laxation process in fine grain (<300nm) TiO2 while two relaxationprocesses were found in coarse grain TiO2. Activation energy of bothof these two relaxation processes was determined and their possibleorigins were discussed. In addition, D.C. conductivity and its activa-tion energy was also measured and compared to A.C. response. It wasfound that TiO2 ceramics with grain size less 300nm possess supe-

rior dielectric properties in terms of low conductivity (<10-14 s/cm),low dielectric loss (<1%) and high dielectric breakdown strength(>1.5 MV/cm)

3:00 PMGrowth of Ferroelectric Fluoride Single Crystals and UV QPM-SHG Emission (Invited)K. Shimamura*, E. Víllora, National Institute for Materials Science, Japan; N.Senguttuvan, M. Aoshima, K. Sumiya, Hitachi Chemical Co., Ltd., Japan; N.Ichinose, Waseda University, Japan

All solid-state lasers emitting in the UV/VUV wavelength region arestrongly requested in order to substitute currently used excimerlasers. Second harmonic generation (SHG) is achieved by non-linearoxide crystals; however, these show solarization problems and a lim-ited SHG wavelength. Instead of these, we propose the use of fluorideferroelectric crystals for SHG by the quasi phase-matching (QPM)technique, which is non-critical at any wavelength. BaMgF4 (BMF) isa potential candidate currently under investigation. It exhibits a widetransparency from VUV to IR wavelength region. The first 2 inch sin-gle crystal of BMF has been grown. The ferroelectric character of thiswas evidenced by the measurement of the polarization hysteresis.Single crystal c-cut plates were periodically poled (PP) with differentperiods for the fabrication of QPM devices. We have recently suc-ceeded to demonstrate SHG emission from PP-BMF crystals using1064 nm Nd:YAG and Ti:sapphire lasers as fundamental lightsources.

3:20 PMCeramic-Polymer Dielectric Composites Produced via DirectionalFreezingE. P. Gorzkowski*, M. Pan, Naval Research Laboratory, USA

Freeze casting was used to construct ceramic-polymer compositesin which the two phases are arranged in an electrically parallel con-figuration. By doing so, the composites exhibit dielectric constant(K) up to two orders of magnitude higher than that of compositeswith ceramic particles randomly dispersed in a polymer matrix. Inthis technique, an aqueous ceramic slurry was frozen uni-direc-tionally to form ice platelets and ceramic aggregates that werealigned in the temperature gradient direction. The compositescould be made of a variety of ceramics (Barium Titanate, PMN-PT,and PZT) and infiltrated with low viscosity polymers such asepoxy, polyurethane, and silicone. One additional benefit to thisprocessing technique is the observation of graceful failure behaviorduring dielectric breakdown testing. This study observed the corre-lation between tailored microstructure and composite propertiessuch as dielectric constant, loss, hysteresis, breakdown and piezo-electric coefficient.

3:40 PMCeramic-polymer composite with equal permittivity-permeabilityfor antennaT. B. Do*, J. W. Halloran, University of Michigan, USA; J. L. Volakis, OhioState University, USA

Materials with equal dielectric permittivity and magnetic permeabil-ity are designed for antenna substrates. In this research, we report onpolymer matrix composites with Co2Z hexagonal ferrite, spinelMgFe2O4 and magnesium calcium titanate dielectrics in polyethyl-ene (PE) and silicone elastomers. At 300 MHz, equal permittivity andpermeability could not be achieved either with isotropic oranisotropic textures. The contribution of permeability (μ’ = 8) ofCo2Z was not comparable to that of permittivity (ε’ = 12)for pro-duced materials to obtain the equality of these two properties. At 6MHz, the combination of spinel MgFe2O4 and magnesium calciumtitanate can produce isotropic two phase composites with equal per-mittivity and permeability.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 139

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania140

4:00 PMPolarization Measurements of Molded Liquid CrystalPolymer/Titania CompositesB. R. Dantal*, A. Saigal, M. Zimmerman, M. Afsar, K. Korolev, U. Khan, TuftsUniversity, USA

Polarization of injection molded liquid crystal polymer/Titania com-posite parts have been investigated in broad band millimeter wavefrequency range. The measurements have been performed by usingtwo different spectroscopy techniques. Dielectric properties of liquidcrystal polymer/Titania composites have been determined in broadband millimeter wave frequency range. A correlation between dielec-tric properties and dispersed Titania volume percent has been ob-served using the two spectroscopy techniques. It is found that the ab-sorption coefficient and loss tangent is a strong function of theoutput power of the sources of the incident radiation. On the otherhand, refractive index and real permittivity values measured fromboth spectroscopy techniques are similar. In addition, it has beenfound that transmittance level and absorption losses depend on theorientation of the samples with respect to the orientation of electricand magnetic fields in the incident electro-magnetic wave.

Electronic & Magnetic Materials: PerovskiteOxides: Films, Nanostructures, Properties,and Applications

Physical Properties of Perovskite Oxides IRoom: 316Session Chairs: Qi Li, Pennsylvania State University; Hans Christen,Oak Ridge National Laboratory

2:00 PMMixed Ionic-electronic Conducting Perovskite-based Oxides(Invited)A. Manthiram*, University of Texas at Austin, USA

Perovskite and perovskite-related intergrowth oxides exhibitingmixed oxide ion and electronic conduction find applications as elec-trocatalysts in solid oxide fuels cells (SOFC). The major challenges insuccessfully employing such oxides in SOFC are in realizing adequatecatalytic activity, high electronic and oxide ion conductivities, lowthermal expansion mismatch between the electrocatalyst and theelectrolyte, and long-term chemical stability. This presentation willfocus on the mixed conducting properties of (i) orderedLnBaCo2O6-δ (Ln = lanthanide) perovskites consisting of BaO andoxygen deficient LnO1-δ rock salt layers alternating along the c axisand (ii) perovskite-related Sr3-xLaxFe2-yCoyO7-δ and La4-xSrxFe3-yCoyO10-δ intergrowth oxides consisting of double or triple per-ovskite layers alternating with double rock salt layers along the c axis.The chemical, structural, electronic, ionic, and thermal expansionproperties as well as electrochemical performances in SOFC of theseoxides will be presented.

2:40 PMThe study of Morphotropic Phase Boundary in PZT-PZN systemsG. Srivastava*, A. M. Umarji, Indian Institute of Science, India

Lead based ferroelectrics have been exploited for their potential ap-plications in high piezoelectric devices. Among these, ABO3 typePbZr1-xTixO3 solid solution has been of great interest due to thepresence of morphotropic phase boundary (MPB). Thus, it is impor-tant to quantitively determine the phases as it affects the materialproperties. A systematic structural investigation was carried out onPZT1-y-PZNy systems. The compositions were prepared by the two-step solid-state method. The samples sintered at 12800C show aver-age particle size of 1-2μm. The increase in concentration of PZN, re-sulted in shifting of MPB towards PbZrO3 composition. An effort hasbeen made to determine quantitatively the MPB phase contents with

variation in Zr/Ti ratio using Rietveld Refinement program FULL-PROF 2006 on High resolution XRD data.The width of MPB getsconsiderably larger for 20 mol% of PZN addition from Δx =0.01 to0.06. This can be attributed to lower particle size of samples resultingfrom the preparation method adopted.

3:00 PMComplex Perovskites: Chemical order, crystallographic distortionsand physical properties (Invited)P. M. Woodward*, Ohio State University, USA

In this talk I will discuss our studies of complex perovskites with aparticular emphasis on atomic ordering over various length scalesand its impact on the structure and properties of these materials. Iwill show some examples of perovskites where cation ordering is crit-ical for properties and applications. In the A2MnMO6 (M = Ru, Nb,Sb) systems the coupling between orbital ordering and octahedraltilting is demonstrated and exploited to control the magnetic proper-ties. Next I will discuss examples of perovskites which undergo si-multaneous ordering of the larger A-site cations and the smaller B-site cations. These materials show a remarkable nanoscale periodicphase separation. They also have characteristics that indicate possiblemultiferroic behavior. Finally if time permits I will discuss our stud-ies of oxynitride perovskites, AMO2N (A = Ba, Sr, Ca; M = Ta, Nb),where novel dielectric behavior is closely linked to the details of theanion order.

3:40 PMPhase Transitions and Dielectric Properties in Bi(Zn1/2Ti1/2)O3-ABO3 Perovskite Solid Solutions (Invited)D. Cann*, C. Huang, Oregon State University, USA; N. Vittayakorn, KingMongkut Institute of Technology Ladkrabang, Thailand; A. Prasatkhetragarn,P. Ketsuwan, Chiang Mai University, Thailand

Perovskite solid solutions based on the system Bi(Zn1/2Ti1/2)O3-ABO3 were obtained via solid-state processing techniques. The crys-tal structure and ferroelectric phase transitions were studied bymeans of x-ray diffraction and dielectric measurements. A stable per-ovskite phase was obtained for Bi(Zn1/2Ti1/2)O3 solutions contain-ing up to 50 mole% of a high tolerance factor end member. The per-ovskite phase generally transitioned to lower symmetryorthorhombic or rhombohedral phases with increasedBi(Zn1/2Ti1/2)O3 content for all compositions. Interestingly, in solidsolutions with BaTiO3, NaNbO3, and KNbO3, the Curie temperatureexhibits a minimum at approximately 10-20 % Bi(Zn1/2Ti1/2)O3 in-dicating a destabilization of the ferroelectric phase. However, withoff-center ion doping via substitution of Li on the A-site, the Curietemperature increased and the phase transition shifted from second-order to approaching a first order phase transition.

Environmental & Energy Issues: Ceramicsand Glass for Waste Minimization,Stabilization, and Disposition

Vitrification Technology Development and TestingRoom: 326Session Chairs: Josef Matyas, Pacific Northwest National Lab;Amanda Youchak, Savannah River National Lab

2:00 PMFull-Scale Cold Crucible Test on Vitrification of Savannah RiverSite SB4 HLW SurrogateS. Stefanovsky*, A. Kobelev, V. Lebedev, M. Polkanov, V. Gorbunov, A.Ptashkin, O. Knyazev, SIA Radon, Russian Federation; J. C. Marra, SRNL,USA; K. D. Gerdes, US DOE, USA

A full-scale cold crucible test was conducted for 66 hrs on SavannahRiver Site SB4 HLW surrogate using a 418 mm diameter crucible. Frit

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 140

Tues

day

PM

www.matscitech.org 141

503-R4 (8 wt.% Li2O, 16 wt.% B2O3, 76 wt.% SiO2) was added to thewaste at a ratio 50 wt.% waste calcine:50 wt.% frit. Slurry was pre-pared in two portions: 1) frit and mixture of chemicals simulatingwaste (~750 kg) and; 2) frit and chemically prepared waste surrogate(~1,300 kg) with water content of ~27 and ~50 wt.%. Approximately875 kg of vitrified product was obtained from the testing. Average op-erating parameters were: vibration power - 121.6 to 134.1 kW; feedrate (capacity) - 25.1 to 39.8 kg/hr; glass pour rate (productivity) -14.0 kg/hr; specific energy expenses for feed processing – 3.4 to 4.8kW×hr/kg; specific energy expenses for glass production (meltingratio) - 8.7 to 9.6 kW×hr/kg; and specific glass productivity - 2453kg/(m2xd).

2:20 PMNETEC Cold Crucible Induction Melter Demonstration for SRNLwith Simulated Sludge Batch 4 DWPF WasteM. E. Smith*, A. B. Barnes, A. S. Choi, J. C. Marra, WSRC-SRNL, USA; T.Hwang, C. Kim, NETEC/KHNP, USA

Cold Crucible Induction Melter (CCIM) technology is being consid-ered as a possible next generation melter for the Defense Waste Pro-cessing Facility (DWPF). Initial and baseline CCIM demonstrationsthat vitrified a Sludge Batch 4 (SB4) simulant at a waste loading of50% (versus about 38% in the current DWPF Melter) were per-formed by NETEC in South Korea via a subcontract from the Savan-nah River National Laboratory. This higher waste loading wasachieved by using a CCIM which can run at higher glass temperatures(1250 C and higher) than the current DWPF Melter (1150 C). Higherwaste loadings would result in less canisters being filled and fasterwaste throughput at the DWPF. The main demonstration objectiveswere to determine the maximum melt rate/waste throughput for theNETEC CCIM with a Sludge Batch 4 simulant as well as determinethe viability of this technology for use in the DWPF.

2:40 PMMicrowave and radiofrequency ultra fast melting of hazardousand radioactive wastesC. Leonelli*, I. Lancellotti, L. Barbieri, P. Veronesi, University of Modena andReggio Emilia, Italy; M. La Robina, ANSTO, Australia

Ultra fast melting techniques are proposed for immobilising haz-ardous, toxic and / or radioactive wastes with the aim to reduce cru-cible contamination or batch components volatilizations. The wastemay be either a conductive or an insulating dielectric material; there-fore the proposed processing technologies operate at microwave andradio frequencies. Using this very fast melting technique, we proposeto develop a waste form based on SYNROC technology to design a ce-ramic or a glass-ceramic material capable of hosting hazardous or ra-diotoxic ions and immobilising them. The process is rapid and energyefficient with no crucible contamination and minimal loss of volatilesby using a pressurised reaction chamber.

3:00 PMInternational Studies of Enhanced Waste Loading and ImprovedMelt Rate for High Al2O3 Concentration Nuclear Waste GlassesK. M. Fox*, D. K. Peeler, J. C. Marra, Savannah River National Lab, USA; A.Aloy, A. V. Trofimenko, R. Soshnikov, V. G. Khlopin Radium Institute, RussianFederation

High level radioactive wastes, a legacy of Cold War plutonium pro-duction, are being vitrified at the Savannah River Site for final dispo-sition in a geologic repository. Some of these wastes contain highconcentrations of aluminum and sodium, which can make it diffi-cult to produce durable waste glasses at high waste loadings. SRNLand the V. G. Khlopin Radium Institute are collaborating to developfrit compositions that, when mixed with high aluminum concentra-tion wastes, produce glasses with acceptable durabilities at reason-able waste loadings. Rate of melting is also important for theseglasses as it impacts the amount of time necessary for vitrificationand site cleanup. Frit compositions are tailored to help improve melt

rate, and their effects are evaluated using smaller scale, liquid-fedmelters. A summary of these studies will be provided. This work issponsored by the Department of Energy Office of EnvironmentalManagement.

3:20 PMLong-Term Molten Glass/Vapor Space Corrosion Testing for theSavannah River Site Defense Waste Processing FacilityK. Imrich*, Savannah River National Lab, USA

Long-term molten glass corrosion tests using non-radioactive simu-lants were performed to evaluate the corrosion resistance of Inconel690 exposed to several feed chemistries that were to be processedthrough the Defense Waste Processing Facility (DWPF) vitrificationmelter. The batches, SB2-3 and SB3, are blends from tanks 51, 19, 18,7, and precipitates (metal oxide and radionuclides) from F and HCanyons. The SB2-3 feed was characteristic of the actual feed chem-istry while the SB3 glass contained significantly higher sulfate andchloride concentrations. Coupons were exposed to the 1150 °Cmolten glass for six weeks. Results of the SB2-3 test indicated thatmaterial loss due to molten glass corrosion was extremely low, 0.007in/yr. Material loss for coupons exposed to the SB3 feed was more se-vere, 0.15 in/yr, which demonstrates the synergistic effect that sulfurand chloride containing salts can have on the performance of In-conel 690.

3:40 PMU.S. DOE Initiated Performance Enhancements to the HanfordWTP LAW Vitrification SystemI. M. Muller, K. S. Matlack, I. L. Pegg, Catholic University of America, USA; I.Joseph*, B. W. Bowan, EnergySolutions, Inc., USA; A. A. Kruger, United StatesDepartment of Energy, USA; L. Holton, Pacific Northwest NationalLaboratory, USA; K. Gerdes, United States Department of Energy, USA

At the Hanford Site, the U.S DOE is constructing the Tank WasteTreatment and Immobilization Plant (WTP) to vitrify radioactivewaste stored in underground tanks. A key part of DOE’s strategy tooptimize the performance of this plant is to maximize waste loadingin the glass product, which for Hanford Low Activity Waste (LAW)involves increasing sodium and sulfur loadings. This paper presentsthe results of glass formulation development and melter testingwith simulants that cover the range of sodium and sulfur concen-trations projected for the LAW. The glass formulations were charac-terized with respect to relevant product quality and processing re-quirements. Melter runs were performed to collect processing data,including glass production rates, off-gas emissions, and sulfatephase formation. The data obtained are reviewed to assess theachievable waste loadings and the properties that constrain wasteloading. The implications for significant cost and schedule reduc-tions are discussed.

4:00 PMU.S. DOE Initiated Performance Enhancements to the HanfordWTP HLW Vitrification SystemH. Gan, W. K. Kot, K. S. Matlack, I. L. Pegg, Catholic University of America,USA; I. Joseph, B. W. Bowan*, EnergySolutions, Inc., USA; A. A. Kruger, UnitedStates Department of Energy, USA; L. Holton, Pacific Northwest NationalLaboratory, USA; K. Gerdes, United States Department of Energy, USA

At the Hanford Site, the U.S DOE is constructing the Tank WasteTreatment and Immobilization Plant (WTP) to vitrify radioactivewaste that is stored in underground tanks. A key part of DOE’s strat-egy to optimize the performance of this plant is to maximize wasteloading in the glass product. This paper presents the results of glassformulation development and melter testing with simulated HanfordHigh Level Waste (HLW) with high concentrations of troublesomecomponents such as bismuth, chromium, and aluminum. The testglass formulations and the products from the melter runs were char-acterized with respect to all of the relevant product quality and pro-cessing requirements. Processing data including glass production

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 141

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania142

rates, and off-gas emissions were also collected. The data are reviewedto assess the achievable waste loadings, the properties that constrainwaste loadings, and the effect of composition on melt rate. The impli-cations for significant cost and schedule reductions are discussed.

Environmental & Energy Issues: EnergyMaterials

Other Energy Materials IIRoom: 327Session Chairs: Kevin Howard, The Dow Chemical Company;Dileep Singh, Argonne National Laboratory

2:00 PMCorrosion of Superalloys in Gaseous Atmospheres with HighContents of H2O and CO2E. J. Magee*, F. S. Pettit, G. H. Meier, University of Pittsburgh, USA

The resistance to oxidation of turbine blade materials in high temper-ature environments with high concentrations of water vapor and car-bon dioxide is being studied to facilitate evaluation of these materialsfor use in future power plants. Water vapor is known to accelerate ox-idation related degradation mechanisms in many turbine blade mate-rials systems. Here three nickel-based superalloys, IN 738, GTD 111,and René N5 are being exposed in cyclic oxidation. SEM imaging andweight change versus time data are being used to compare the highwater vapor environment to a baseline of exposure to high tempera-ture in dry air.

2:20 PMVolume of Activation for the Corrosion of Type 304 SS in Highsubcritical and Supercritical Aqueous SystemsD. D. Macdonald*, Penn State University, USA; X. Guan, Shell InternationalExploration & Production, USA

In this study electrochemical noise analysis (ENA) is used to analyzethe effect of pressure on corrosion reactions in high subcritical andsupercritical aqueous systems (SCAS). A model is applied to studythe effect of pressure on corrosion rates of metals in SCAS, with em-phasis on contributions from activation, the degree of dissociationsof aggressive species, and the system isothermal compressibility. Ex-periments were carried out to estimate the pressure dependence ofelectrochemical corrosion rates of Type 304 SS in HCl at subcriticaland supercritical temperatures. The study shows that the volume ofactivation of electrochemical corrosion of metals is pressure de-pendent in SCAS. The contribution from the volume of activationplays a dominant role on the relative corrosion rate at high subcriti-cal temperatures.

2:40 PMPreparation of electrocatalytically active RuO2/Ti electrodes byPechini methodO. Kahvecioglu*, S. Timur, Institute of Science and Technology, Turkey

In this study, DSA® type porous ruthenium oxide coated titaniumelectrodes with different coating masses were prepared by Pechinimethod from a polymeric precursor at different decomposition tem-peratures. The influences of temperature on the morphology and themicrostructure of RuO2 formed on titanium were investigated bySEM and thin film-XRD. This work aimed to prepare electrocatalyti-cally active electrodes showing high stability during oxygen evolutionreaction. Linear Sweep Voltammetry (LSV) tests were performed in 1M H2SO4 after a 1-hour-constant anodic polarization at 20 mA/cm2.Tafel slopes of 55-60 mV/dec were obtained. The electrodes preparedat lower temperatures show lower anode potentials than that of pre-pared at higher temperatures. Increasing of the coating mass showedan increase in the coating stability of the electrode. Similar electrocat-alytical properties were determined for the electrodes having differ-ent oxide loading obtained at 450 degrees Celcius.

3:00 PMType I Hot Corrosion of MCrAlX-Type Overlay CoatingsM. N. Task*, N. M. Yanar, B. Gleeson, G. H. Meier, F. S. Pettit, University ofPittsburgh, USA

The type I hot corrosion of Ni-35Cr-12Al-0.5Y, Co-18Cr-12Al-0.5Y,and Ni-20Co-18Cr-12.5Al-0.6Y-0.4Si-0.25Hf (wt. %) has been inves-tigated. Specimens included the above-mentioned alloys in bulk formand deposited on a René -N5 substrate via low-pressure plasma spray.Experiments consisted of exposure at 900°C in the presence ofmolten sodium sulfate deposits in laboratory air. The microstructuresof the coatings, substrates, and corrosion products were thoroughlyinvestigated using scanning electron microscopy and X-ray diffrac-tion. The kinetics of the degradation were quantified with weight-change measurements.

Nuclear MaterialsRoom: 327Session Chair: Ronald Ballinger, Massachusetts Institute ofTechnology

3:20 PMEffect of Oxygen Potential on Crack Growth in Alloys forAdvanced Energy SystemsR. G. Ballinger*, J. K. Benz, J. Kim, MIT, USA

The effect of oxygen partial pressure on fatigue and SCC growth ratesin alloys 617, 230 and 908 have been studied using both static and fa-tigue loading over the temperature range of 500-750C (with a focus on650C) and over an oxygen partial pressure range from 0-0.001 atm oxy-gen partial pressure. Tests are being conducted at either constant stressintensity factor, K, or constant K range. Gas chemistry is measured onboth the inlet and outlet as well as in-situ with a probe that directly atthe specimen surface. Results indicate that at low oxygen partial pres-sures all of the crack growth rates in fatigue condense to a value of ap-proximately 10-7 m/cycle in fatigue and ~10-10 m/cycle in static crackgrowth for materials containing > 15 wt% Cr. For low Cr materials(alloy 908) a threshold in oxygen partial pressure of ~ 10-7 atm existsabove which crack growth in fatigue becomes a function of frequencyand hold time. Factors of up to 1000X increases have been observed.

3:40 PMFEM study of delayed hydride cracking in zirconium alloy fuelcladdingM. Uno*, M. Ito, H. Muta, K. Kurosaki, S. Yamanaka, Osaka University, Japan;K. Ogata, Japan Nuclear Energy Safety Organization, Japan

Delayed hydride cracking(DHC) has been observed at ramp test for irra-diated PWR fuel claddings. It is important to analyze the cracking prop-agation behavior for evaluation of the safety improvement of the high-burnup claddings. Hydrogen diffusion behavior plays an important rolein the DHC process. However, the behavior is affected by many factors,such as the defects, orientation, hydrogen concentration gradient, tem-perature gradient, and pressure gradient in the claddings. In this study atfirst the temperature and stress distribution of the cladding was simu-lated and then the hydrogen diffusion behavior near the crack tip was cal-culated by FEM using ABAQUS ver.6.5. The hydrogen quickly redistrib-uted according to the stress distribution. The hydrogen concentration atthe crack tip increased more than 10 % within a few seconds in most con-ditions. The crack growth rate was also discussed from the results.

4:00 PMAb initio Study of the Influence of Pressure on the HydrogenDiffusion Behavior in Zirconium Hydrogen Solid SolutionY. Endo*, M. Ito, H. Muta, K. Kurosaki, M. Uno, S. Yamanaka, OsakaUniversity, Japan

Hydrogen diffusion behavior plays an important role in delayed hy-dride cracking process for irradiated fuel claddings. The hydrogendiffusion is affected by many factors. Therefore, it is difficult to evalu-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 142

Tues

day

PM

www.matscitech.org 143

ate the hydrogen behavior by way of experiment only. In this study,the influence of pressure on the hydrogen behavior in pure zirconiumwas tried to be analyzed by electronic state calculation. The electronicstate was calculated by CASTEP (Cambridge Serial Total EnergyPackage) based on density function theory (DFT). In the calculationof the H2, Dmol3 based on DFT was used. We found that partial molevolume of hydrogen decreased with the pressure. The hydrogen dis-solution enthalpy increased with the pressure. Besides this, it wasclarified that the influence of the stress along c axis was stronger thanthat of the stress along a axis.

Environmental & Energy Issues: Fuel Cells:Materials, Processing, Manufacturing,Balance of Plant and Systems Operation

Cell and Stack Component Materials IRoom: 325Session Chairs: Prashant Kumta, University of Pittsburgh; DonaldCollins, National Energy Technology Lab

2:00 PMCarbonate Fuel Cell Materials and Products (Invited)C. Yuh*, A. Hilmi, G. Xu, J. Colpetzer, J. Nikhil, D. Kelley, M. Farooque,FuelCell Energy, Inc., USA

High temperature carbonate fuel cells are recognized as the cleanest,mostefficient and cost-competitive power generation option for commercialand industrial customers. It operates at a high enough temperature thatthe heat by-product can be used for cogeneration applications. MW andsubmegawatt size units are operating worldwide. The current generationplants have shown an electrical efficiency of between 45 and 47 percentand an overall energy efficiency of between 65 to 80 percent in cogenera-tion and combined cycle applications. Plants with newer BOP and longerlife stack designs have evolved based on initial field experience.Significantprogress has been made in carbonate fuel cell technology development,manufacturing, product engineering, and field operation. A comprehen-sive review of this product and material status is presented in this paper.

2:40 PMSOFC materials evaluation in a standard “stack” test fixtureY. Chou*, J. Stevenson, G. Xia, J. Templeton, G. Maupin, J. Templeton, P.Singh, X. Zhou, Pacific Northwest National Laboratory, USA

Pacific Northwest National Laboratory has been developing variousmaterials including sealant, coating, and electrodes for SOFC applica-tions. In this work we conducted material set evaluation using a stan-dard “stack” test fixtures. The test fixtures consist of two heat ex-changer blocks for air and fuel preheating, one ceramic PEN towindow frame plate, one anode interconnect plate, and one cathodeinterconnect plate. Candidate materials set for evaluation are ceramicPEN to window frame refractory glass seal, a hybrid mica-based com-pressive seal at heat exchangers, a Mn-Co spinel protective coating,and SS441 as metallic interconnect. Steady-state and thermal cyclingwill be conducted of the single cell “stack” testing using 97% H2 andair at 800C. Electrochemical performance and impedance data will becollected. Post-mortem analysis with optical microscopy andSEM/EDS will be conducted to provide insights to interpret the per-formance/degradation of 2”x2” single cell testing with candidate ma-terials set.

3:00 PMFinite element analysis of nonlinear deformations of Ni-YSZ usingstochastic reconstructionsJ. Johnson*, J. Qu, Georgia Institute of Technology, USA

Porous ceramic-metal composites, such as nickel zirconia (Ni-YSZ),are widely used as the anode material in solid oxide fuel cells (SOFCs).For the anode supported planar cells, the thermomechanical behaviorof the porous cermet directly affects the reliability of the cell. In the

cell, residual stresses take place in the material due to the thermal mis-match of nickel and YSZ; viscoplasticity occurs as the fuel cell isheated to operating temperature for long periods of time, and internalstresses can be high from mechanical constraints. This work used astochastic reconstruction procedure to recreate multiple instances ofthe Ni-YSZ microstructure for finite element analysis. The nonlineardeformation due to the viscoplasticity in nickel is studied with respectto temperature, and the statistical variation of the stress strain curvesis investigated. The research illustrates the relationship between non-linear deformations and the microstructural features of the anode.

3:20 PMThe General Principles of the Materials Selection andQualification for the PEM Fuel CellS. Loif*, Ballard Power Systems, Canada

This presentation will be dedicated to the general principles of thePEM materials selection and qualification process, which has beenimplemented at Ballard Power Systems. The new materials developedfor the fuel cell application, and in particular, unit cell materials, un-dergo a selection and qualification process. In the qualificationprocess, extensive testing is done to ensure that the material meets thecomponent design requirements. The major stages of the materialsqualification process will be discussed in the presentation and exam-ples of different materials qualification procedures will be given. Inaddition, some risks of fuel cell contamination related to the materialselection and qualification will be outlined.

3:40 PMOxidation Kinetics of Manganese Cobaltite Spinel ProtectionLayers Performance on Sanergy HT for SOFC InterconnectApplicationsE. Alvarez*, A. M. Meier, Alfred University, USA; K. Weil, Z. Yang, PacificNorthwest National Lab, USA

Chromia forming ferritic stainless steels exhibit many desirable quali-ties for intermediate temperature SOFC interconnect applications.However, the need to prevent chromium poisoning while maintaininga low interfacial electrical resistance, has also led to an interest in thedevelopment of electrically conductive protective coatings. In thisstudy, screen printed (Mn,Co)3O4 coatings were applied to a newly de-veloped ferritic SS alloy, Sanergy HT(Cr-21.9%, Ni-0.5%, Mo-0.88%,Nb-0.60%, Si-0.05%). The oxidation behavior was evaluated for longterm exposures (up to 1500 hours at 800°C) for both bare and coatedalloy samples. The oxidation kinetics was evaluated using weight gainand scale thickness measurements. In addition, the chrome oxide scalemicrostructure was characterized. The effect of the oxide layer on elec-trical performance was studied using ASR measurements. The resultswere compared to previous work done using Crofer22 APU.

Environmental & Energy Issues:Thermoelectric Materials: Science,Technology and Applications

Oxide Thermoelectric MaterialsRoom: 324Session Chairs: Ryoji Funahashi, National Institute of AdvancedIndustrial Science & Technology; Hiromichi Ohta, NagoyaUniversity

2:00 PMMaterials Development for Perovskite-type Thermoelectric OxideModules (Invited)A. Weidenkaff*, R. Robert, L. Bocher, P. Tomes, M. H. Aguirre, Empa,Switzerland

Solar energy on earth would be more than enough to cover today’sworld energy consumption, if the direct thermoelectric energy conver-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 143

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania144

sion, i.e. the transformation concentrated solar heat into electricity be-comes fast and highly efficient. For the realisation of a solar thermo-electric converter stable p- and n- type thermoelectric ceramics are de-veloped to be tested in Thermoelectric Oxide Modules (TOM). A verypromising approach to reduce the thermal conductivity, which is lead-ing to very high theoretical values of ZT, is to increase the amount ofgrain boundaries by producing nanoscaled semiconductor thermo-electric materials. As p-type materials a set of Ni-doped lanthanidecobaltates with various compositions are chosen and synthesised by achimie douce method. Here the power factor is optimised by appropri-ate variations of the crystallographic structure. For the n-type leg tai-lor-made Nb-doped manganates with small crystallite size are studied.

2:30 PMFirst Full Perovskite Type Oxide Thermoelectric ModuleP. Tomes*, M. Trottmann, L. Bocher, R. Robert, E. Hack, S. Toggweiler, Empa- Swiss Federal Laboratories for Materials Testing and Research, Switzerland;A. Bitschi, ETH, Switzerland; J. Hejtmanek, ASCR, v.v.i, Czech Republic; A.Weidenkaff, Empa - Swiss Federal Laboratories for Materials Testing andResearch, Switzerland

Four-legs oxide thermoelectric module (TOM) has been fabricatedby combining p- and n-type oxide thermoelements made ofGdCo0.95Ni0.05O3 and CaMn0.98Nb0.02O3 respectively. In the module p-and n-type thermoelements are connected electrically in series andthermally in parallel. The electrical contacts are made using Ag-CuOmixture and good thermal contacts are ensured by sandwiching thethermoelements between alumina plates. The maximum outputpower, resistance and open circuit voltage of TOM was measured upto the temperature gradient ΔT = 500 K. The evaluated characteristicswere compared with theoretical estimations using micro - IR cameratemperature distribution measurements. TOM was tested in the high- flux solar furnace to simulate the ability of conversion of solar en-ergy in to electrical energy. The conversion efficiency was calculatedfor different ΔT and the maximum output power at ΔT = 500 K was0.04 W leading to power density of ~ 0.125 W/cm3.

2:50 PMStructure and Thermoelectric Properties of Compounds in theCa-Sr-Co-O SystemW. Wong-Ng*, G. Liu, E. Thomas, M. Otani, Q. Huang, N. Lowhorn, NationalInstitute of Standards and Technology, USA; J. A. Kaduk, INEOSTechnologies, USA

In recent years, the discovery of novel thermoelectric oxides has beenof great interest to the thermoelectric community because of the sta-bility of oxides at high temperature. One specific family, the layeredcobaltites that include Ca2Co3O6 and Ca3Co4O9 has attracted consid-erable attention because of the combination of large Seebeck coeffi-cient and low resistivity. These compounds also have high electronicanisotropy. This paper discusses the crystal chemistry, crystallogra-phy, and thermoelectric property measurements of several series ofcompounds in the ternary oxide system, Ca-Sr-Co-O, including(Ca,Sr)2Co3O6, (Ca,Sr)3Co4O9, and other strontium-rich com-pounds. The phase equilibrium diagram of the Ca-Sr-Co-O systemwill also be described.

3:10 PMThe Origin of Thermoelectricity in Ca3Co4O9T. A. Tyson*, Z. Chen, New Jersey Institute of Technology, USA; Q. Jie, Q.Li, Brookhaven National Laboratory, USA; J. Tu, The City College of NewYork, USA

We have combined temperature dependent local structural measure-ments with first principles density functional calculations to developa three dimensional local structure model of the misfit system[Ca2CoO3][CoO2]1.61 (referred to as Ca3Co4O9) which has a rock-salt structure stacked incommensurately on a hexagonal CoO2 lat-tice. The local structural measurements reveal a low coordination ofCo(2) in the rock salt layer. The temperature dependence of the Co(1)

in the CoO2 layer is found to be normal above ~75K. Density func-tional computations show that the reduction of the coordination ofCo(2) is due to the formation of chains of Co(2)Ox in the a-b planelinked to the Ca-O layers by c-axis Co(2)-O bonds. The reduced di-mensionality introduced by the chain-like structure in the rock-saltlayer and high atomic order in the CoO2 layer may be the origin ofthe low thermal conductivity and high electrical conductivity in therespective layers yielding a high thermoelectric figure of merit.

3:30 PMFar-infrared Magneto-Spectroscopic Studies of Ca3Co4O9 ThinFilms and Single CrystalsJ. J. Tu*, D. Dimitrov, The City College of New York, USA; W. Si, Q. Li,Brookhaven National Lab., USA

We have carried out far-infrared magneto-spectroscopic studies ofCa3Co4O9 thin films in Faraday geometry as a function of frequency,magnetic field and temperature with the emphasis on the couplingbetween the lattice, the charge and the spin degrees of freedom. Farinfrared transmission reduces at low frequencies in the presence ofmagnetic field corresponding to negative magneto-resistance. Below20K, hysterisis occurs. However, the spectral responses to magneticfield and temperature are different. This indicates that the negativemagneto-resistance is due to reduced magnetic scattering when Cospins become aligned. Further infrared studies will be performedwith magnetic field parallel to the CoO2 layers. A good understandingof our infrared results should shed light on the origin of highthermo-power in these 2D-layered cobaltates. Supported by CUNY-RF-80209-11-13, DOE-AC02-98CH10886 and NSF-DMR-0451605.

3:50 PMJonker Analysis of Oxides for Thermoelectric ApplicationsD. Proffit*, E. Hopper, K. Muangnapoh, N. Mansourian-Hadavi, T. O. Mason,Northwestern University, USA

Oxide thermoelectrics show promise for high temperature thermo-electric applications. Jonker analysis was applied to a range of oxidethermoelectric materials to determine optimal power factors. Thethermoelectric figure of merit can be maximized by maximizing thepower factor and minimizing thermal conductivity. The present workfocuses on the power factor only. In Jonker analysis, the power factoris determined by the high conductivity x-intercept when plotting See-beck coefficient versus ln of conductivity. This intercept correspondsto the density of states-mobility product, which differs among mate-rials. All extrinsic Jonker slopes must be ±k/e for this analysis to apply,therefore only traditional semiconductors can be analyzed. By com-paring data for various doping levels of a material, the optimizedpower factor and doping level can be identified. The optimal powerfactors for a range of oxide material systems will be presented. Rami-fications for developing improved oxide thermoelectrics will also bediscussed.

Fundamentals & Characterization: Discoveryand Optimization of Materials throughComputational Design

Multiscale Materials Design IRoom: 303Session Chair: Edwin Garcia, Purdue University

2:00 PMSimulation-based Design of Materials Building Blocks for EnergyApplications (Invited)J. Kieffer*, University of Michigan, USA

Materials simulation has become increasingly reliable as a materials de-sign tool. We use a combination of first-principles calculations and reac-tive molecular dynamics (MD) simulations to construct novel materials

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 144

Tues

day

PM

www.matscitech.org 145

building blocks, predict their stability and inherent properties, and simu-late their assembly into continuous structures. We present two examples:novel molecules for organic photovoltaics, such as polyphenylamines andacene-functionalized polyhedral oligomeric silsesquioxanes (POSS), aswell as POSS-based hybrids for battery or fuel-cell electrolytes. In the for-mer, the goal is to develop organic semiconductors with improved exci-ton conductivities. This is achieved by tuning the HOMO-LUMO energygaps through appropriate radical substitutions and by designing hybridbuilding blocks that tend to assembly into structures with long-rangeorder. For the latter we develop building blocks that assemble into porousstructures that offer specific pathways for the charge carrying species.

2:40 PMFrom Schrödinger’s Equation to the Rolling Mill: QuantitativePrediction of Mechanical Properties in Metals (Invited)D. D. Johnson*, J. Liu, H. Sehitolgu, University of Illinois Urbana-Champaign, USA

Deformation twinning is observed in numerous engineering, chemi-cal, and geological materials. Unlike for shear, no fundamental “law”for twinning stress has emerged. By addressing key multiscale phe-nomena like defect nucleation using density-functional theory inte-grated with mesoscale dislocation mechanics, we resolve this long-standing issue by establishing an expression for onset twinning stressbased upon the defect energy landscape and twin nucleation that pro-vides quantitative agreement to experiment. The theory predicts asimple relation between onset twinning stress and unstable twin en-ergies that is borne out with observed data. A similar approach leadsto design maps for prediction of when “anomalous” behavior inyield-strength (L12 alloys) and ductility (B2 alloys) will be observed.*Funding through NSF grants DMR-03-13489 and DMR-03-12448,as well as DOE through DE-FG02-03ER46026, with computingthrough the Materials Computation Center (DMR-03-25939).

3:20 PMCoupling Density Functional Theory with Continuum Mechanicsfor Alloy Design (Invited)D. Ma*, M. Friák, W. Counts, F. Roters, D. Raabe, J. Neugebauer, Max-PlanckInstitute for Iron Research, Germany

State-of-the-art ab initio methods constitute a solid basis of modernmaterials science and materials design. In order to properly addresscomplex multi-scale phenomena, the theoretical research at atomisticlevel is increasingly combined with higher scale approaches as well asadvanced experimental techniques. The starting point of our ap-proach is parameter-free density functional theory (DFT) calcula-tions which are used to provide theoretical guidance in selecting opti-mum chemical composition of novel alloys with application-tailoredproperties. The DFT data can be then transferred up-scale whencombined with the continuum-based homogenization models. Ourmulti-disciplinary strategy thus allows to predict macro-scale elasticproperties and its performance will be illustrated on two examples,(i) design of novel β-Ti alloys for biomedical applications (implantmaterials), and (ii) development of new ultra light-weight Mg-Li al-loys with optimized engineering properties.

4:00 PMShape memory in nanoscale metallic alloys (Invited)A. Strachan*, A. Thompson, K. Guda Vishnu, Purdue University, USA

Active nanoscale materials are highly desirable in a variety of emerg-ing technologies including nanofluidics and nano electro-mechanicalsystems. Shape memory alloys would be ideal candidates for a largenumber of these applications; however it is not yet known how sizeand dimensionality affect the martensitic phase transition responsi-ble for their unique behavior. I will present recent work on moleculardynamics characterization of the martensitic microstructure of Zrnanowires when the austenite phase (bcc) transforms into martensite(hcp) upon cooling. We find a variety of nanostructures ranging fromsingle domain wires to ones that exhibit the coexistence of the six

possible ones. Furthermore, our simulations reveal that the resultingdomain structure, and consequently thermomechanical properties, isstrongly dependent on the size (radius and length) of the wires. Ourresults indicate that size and dimensionality can be used to tune theresponse of nanoscale shape memory alloys for specific applications.

Fundamentals & Characterization: FailureAnalysis for Problem Solving

Fatigue and Fracture IIRoom: 304Session Chairs: Mike Stevenson, Engineering Systems Inc.; MichaelBurns, Stork Metallurgical Consultants, Inc.; Aaron Tanzer, LehighTesting Laboratories, Inc.; Dustin Turnquist, Engineering Systems Inc.

2:00 PMClassical Fatigue Design Techniques as a Fracture Analytical ToolR. D. Harris*, T. A. Jur, Engineering Design & Testing Corp., USA

The classical method for designing against high-cycle fatigue fractureas based primarily on statistical models derived from laboratory ex-perimental data. This paper considers a number of actual fatiguefractures where the analysis of the fractures, in part, made use of clas-sical high-cycle fatigue resistance design methodology as an analyticaltool. By way of these fracture analyses, the paper demonstrates thatthe long-taught classical methodology is useful and accurate as both adesign and an analysis tool. The usefulness and accuracy of themethod is verified in that it is shown to have predicted actual frac-tures, given known materials, manufacturing histories and serviceoperating conditions. Example analyses include: a fatigue-crackedroll from a paper making machine, a fractured anvil on a steam pow-ered forge and a fractured shaft on a helical ribbon dryer.

2:20 PMReview of Typical Corrosion Related Pipeline FailuresB. C. Rollins*, G. T. Quickel, J. A. Beavers, CC Technologies, Inc. (a DNVcompany), USA

There are more than 2.5 million miles of oil and gas pipelines in theUnited States. This pipeline network is expected to operate safely in adiverse range of internal and external environments. Corrosion re-lated damage is a serious threat to the continued safe operation of thisaging pipeline infrastructure. Corrosion related damage takes manyforms including, but not limited to: localized corrosion, weld-relatedcorrosion, stress corrosion cracking (SCC), and microbiologically in-fluenced corrosion (MIC). This paper attempts to review the mostcommon corrosion related failures experienced on pipelines in the oiland gas industry.

2:40 PMFailure analysis of HP-40 (mod Nb) furnace radiant tubeV. Palaniyandi*, R. B. Allsup, D. Mosher, Aptech Engineering Services, USA

Cast resistant materials like (HP, HK alloys) have been extensivelyused at high temperatures by several industries. The performance ofthese materials largely depends on the stability of the microstructureat service temperatures. This paper discusses the circumferentialcracking failure of a HP-40 (modified Nb) furnace radiant tube after6000 hours of operation. Metallurgical analysis of the failure revealedthe aged microstructure near the rupture has coarse primary carbidesand fine secondary carbides. The ruptured tube revealed subsurfacedecarburization and microvoids. EDX analysis was done to determinethe carbide phase .Bend testing was done to verify the ductility of thetube. SEM analysis of the fracture surface indicated the tube failed bybrittle fracture. The distribution of voids in the tube suggested thetube has undergone creep but has not contributed to the failure.Based on our analysis and operational information, it was concludedthat the tube failed due to brittle failure caused by thermal shock.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 145

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania146

3:00 PMHydrogen Stress Cracking Failures in Subsea Equipment (Invited)M. G. Burns*, Stork Metallurgical Consultants, Inc., USA

Hydrogen stress cracking has caused tens of millions of dollars inlosses in subsea and offshore equipment. As mechanical requirementspush designers to utilize higher and higher strength materials, envi-ronmentally assisted cracking susceptibility becomes a greater andgreater concern. Selected case studies are presented to illustrate thelimitations of several commonly used alloy systems.

3:40 PMFailure Investigation of a Pin Carrier Plate of an Anti-RotationDevice in a MotorS. Nasrazadani*, University of North Texas, USA; D. Hopkins, SouthwestResearch Institute, USA

Parts of the anti-rotation device expelled from a power plant motor wereanalyzed. The “anti-rotation” device prevents the pump from rotatingbackwards when there is pressure in the discharge line and the motor isoff. Parts that were recovered include about 2/3 of the spring compres-sion ring and an“ear”that apparently came from the missing segment ofthe spring compression ring. Results of this investigation revealed that anearly simultaneous overloading occurred on both sides of the pin car-rier plate as indicated by almost equal size fracture.At least two crack ini-tiation sites were identified on both sides of the pin carrier plate. Undertensile loads these surface irregularities can lead to surface cracks result-ing in the fracture of the plate. Areas rich in Aluminum were identified(using Energy Dispersive spectroscopy) in the vicinity of surface irregu-larities. A number of suggestions on avoiding such failure are proposed.

Fundamentals & Characterization: Fatigue ofMaterials: Competing Failure Modes andVariability in Fatigue Life

Fatigue Variability/Statistical AspectsRoom: 305Session Chairs: M. Caton, Air Force Research Lab; Y. Ochi,University of Electro-Communications,Tokyo

2:00 PMMicrostructural Origins of Variability in the Fatigue Properties ofCast Light Alloys (Invited)A. M. Gokhale*, G. R. Patel, Georgia Institute of Technology, USA

During the recent years, there has been increasing thrust towards useof Al- and Mg-alloy castings for structural automotive applications.Increase in the use of such light alloy castings will lead to lower vehi-cle weight, higher fuel efficiency, and lower CO2 emissions. However,successful applications of cast light alloys for structural applicationsrequire production of castings that exhibit reproducible mechanicalresponse (low variability), and have lower cost and reduced productdevelopment cycle time. This contribution concerns analysis of theobserved variability in the fracture sensitive mechanical propertieswith emphasis on fatigue life of cast Al- and Mg-alloy components,and its relationships with microstructural attributes and process con-ditions. The analysis leads to recommendations for minimizing thevariability in the properties of interest.

2:40 PMThe Effect of Constituent Particles in Aluminum Alloys on FatigueDamage Evolution: Statistical Observations (Invited)G. Harlow*, Lehigh University, USA

Constituent particles in aluminum alloys subjected to fatigue con-tribute substantially to damage evolution. The amount of particlesper mm^2 in highly stressed regions is orders of magnitude largerthan the number that actually contribute significantly to damagegrowth. To accurately model the impact of fatigue on the progression

of damage, an appreciation for the role of key particles in aluminumalloys is warranted. The purpose of this paper is to statistically char-acterize particles that directly contribute to damage growth due to fa-tigue. Observations are taken from fatigue experiments subjected to ageneric flight spectrum and conducted on 7075-T6 aluminum alloy,both of which are representative of the wing skin of military aircraft.Particles that are associated with damage evolution are statisticallycharacterized, including their geometrical properties and location.Also, the effect of critical particles on crack nucleation is statisticallycharacterized.

3:20 PMUsing Digital Microstructures to Model Micro-Crack Growth andCoalescence in AA7075S. D. Sintay*, Carnegie Mellon University, USA; J. Brockenbrough, J. Fridy,ALCOA Technical Center, USA; A. D. Rollett, Carnegie Mellon University, USA

Aluminum Alloy AA7075 has a high volume fraction of Al-Cu-Feconstituent particles (1.5%-2.5%). Under fatigue loading these parti-cles will crack and nucleate fatigue cracks into the surrounding alu-minum matrix. For a given region of interest many (tens to hun-dreds) of micro-cracks may propagate simultaneously. Thesemicro-cracks will interact through shielding and or coalescencewhich can result in discontinuous growth rates and contribute tovariability in component lifetime predictions. Digital microstructurereconstructions of the alloy are utilized to simulated the process ofmicro-crack growth and coalescence. In the digital microstructure a3D volume of grains (with assigned crystallographic orientations)and constituent particles are generated and then subsequently sliced.The resulting 2D field of particles embedded in a polycrystalline ma-trix are allowed to crack and nucleate fatigue cracks. Linkup eventsand crack size statistics are tracked as a function of cyclic loading.

3:40 PMNew Data Analysis of P-S-N Curve and Its Application forStructural Materials (Invited)S. Shimizu*, K. Tsuchiya, K. Tosha, Meiji University, Japan

In conventional S-N test curve, which is also known as Wöhler curve,the life test data are plotted with several stress levels, and they are ex-pressed as median ranks, and further it is considered that each lifedistribution follows the log-normal distribution. Therefore, it can besaid that not enough theoretical relationship between the life distri-bution and the S-N curve exists yet. In this report, a new data analysismethod is unveiled for a P-S-N (Probabilistic Stress Life) curve modelby using the log-normal and Weibull based distribution functionscomposing the critical physical meanings of the statistical parame-ters, and application details concerning the rotating bending and al-ternating torsion P-S-N test results obtained by the authors’ group areexplained.

4:00 PMExperimental Analysis and Finite Element Modeling of CyclicThermo-Mechanical ShockK. G. Janssens*, M. Niffenegger, K. Reichlin, Paul Scherrer Institute,Switzerland

In a nuclear power plant under normal operating conditions, cyclicthermo-mechanical shock is sometimes observed in stainless steeltubes used for mixing hot and cold water, and there exists substantialinterest in predicting fatigue behavior in these safety-critical compo-nents. We report on experimental analyses of dedicated thermo-shock experiments simulating loading conditions observed in indus-trial components. Calibrated finite element thermal stress analysesusing mixed isotropic-kinematic hardening laws are evaluated as ameans to estimate the number of cycles to fatigue crack initiation andthe crack propagation rate. The influence of different simulation pa-rameters and the level of detail put in the cyclic-plastic materialmodel is investigated. First observations from the analyses and the ex-periments, suggest that compressive ratcheting, introduced by asym-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 146

Tues

day

PM

www.matscitech.org 147

metric thermal loading of a component, potentially causes the num-ber of cycles to crack initiation to shift.

Fundamentals & Characterization:International Symposium on Defects,Transport and Related Phenomena

Defects and Transport in Ceramics IRoom: 307Session Chairs: Juergen Fleig, Vienna University of Technology;Hans Wiemhöfer, University of Münster

2:00 PMDopant-Vacancy Clustering in Zirconia and Ceria (Invited)A. N. Cormack*, B. Wang, Alfred University, USA

As is well known, at moderate or higher dopant concentrations, clus-tering of dopants and vacancies inhibits the ionic conductivity indoped zirconia and doped ceria. Such clustering is often manifestedin the form of nano-domains. However, the detailed nature of suchnano-domains is still not completely understood, and so we haveused atomistic computer modeling to examine the structure and en-ergetics of clusters of increasing numbers of dopants. We have fo-cused on two systems, scandium-doped zirconia and gadoliniumdoped-ceria, which show differing phase equilibrium behavior. Inthis presentation, we will discuss the relationship between the dispo-sition of oxygen vacancies relative to dopant concentration and con-figuration and the underlying phase equilibria.

2:40 PMThermopower Measurements and Defect Chemistry ofBa0.5Sr0.5CoxFe1-xO3-δδ (x=0,0.2,0.4,0.6,0.8 and 1.0)J. Jung*, S. T. Misture, D. D. Edwards, Alfred University, USA

Ba0.5Sr0.5CoxFe1-xO3-δ(BSCF) is a promising candidate for the cathodein intermediate temperature solid oxide fuel cells (SOFCs) because ofits high electronic and oxide ionic conductivities. Ba0.5Sr0.5CoxFe1-

xO3-δ powders were prepared using a polymerized complex methodwith composition x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0. 4-point DC meas-urements of the electrical conductivity of sintered pellets were madeas a function of temperature (25 °C – 1,000 °C) and partial oxygenpressure (10ppm to 100%). Below ~ 300 °C, the electrical conductiv-ity is thermally activated with activation energies ranging from 0.28to 4.0 eV. The electrical behavior at high temperatures dependsstrongly on composition, ranging from activated conductivity for x =1 to metallic-like conductivity for x = 0. In this study, simultaneousthermopower and DC conductivity measurements as a function ofpO2 and temperature are used to further probe the defect chemistryof BSCF.

3:00 PMDefect mobilities, electronic properties and their impact onoxygen permeation in ceria based mixed conductors (Invited)H. D. Wiemhöfer*, L. M. Kogel, V. Rührup, N. Liu, University of Münster,Germany

Mixed conducting ceria-zirconia solid solutions have become thepreferred oxygen storage compounds in redox catalysts. They alsoexhibit pretty good oxygen permeation properties. If one succeeds toimprove oxygen permeation even further without the use of earth al-kaline dopants, they will be promising candidates as oxygen perme-ation membranes for use in exhaust gases. In an attempt to investi-gate this in detail, we focused on the electrochemistry of electronsand holes, the relation to the electronic structure and strategies of in-fluencing electronic properties by dopants and by the use of com-posites with the background of higher oxygen permeation rates. Re-cent experimental results from time dependent electrochemical

relaxation and photoelectron studies show that this might be a real-istic expectation.

3:40 PMSynthesis and Characterization of Nanocrystalline Niobium-Doped Anatase TiO2E. Hopper*, F. Sauvage, K. R. Poeppelmeier, T. O. Mason, NorthwesternUniversity, USA

Niobium (Nb)-doped anatase TiO2 is a material of interest for usein transparent electrodes and photovoltaic devices. Research on thinfilms has shown Nb to be an effective donor in this system, but theavailable data on electrical conductivity and defect structure in bulkmaterial are often contradictory. Anatase powders with Nb concen-trations from 0 to 10% were fabricated by hydrothermal synthesis.Conductivity of the powders was measured by the Powder SolutionComposite method. Grain size and phase-purity were confirmed byX-ray diffraction (XRD). When the grain size is greater than approx-imately 80 nm, anatase undergoes a phase change to the rutilephase, so a hot press was employed to densify the powder at temper-atures low enough to prevent grain growth. Conductivity of thedense samples was measured by a 4-point probe DC technique andby AC impedance spectroscopy. The results will be analyzed in termsof the donor concentration’s effect on defect structure and electricalproperties.

4:00 PMEffect of Acceptor (Mg) Concentration on the DegradationBehavior of the Electrical Resistance in Acceptor (Mg)-DopedBaTiO3 CeramicsS. Yoon*, C. Randall, The Pennsylvania State University, USA; K. Hur,Samsung Electro-Mechanics Co. Ltd., South Korea

The degradation behavior of the electrical resistance in acceptor(Mg)-doped BaTiO3 ceramics with the increase of acceptor concen-tration was investigated. A series of coarse-grained specimens withdifferent acceptor concentrations were prepared. The resistance athigh temperatures (150~200°C) under high electric field showed adegradation behavior with a critical dependence on acceptor concen-tration in the very small concentration range below ~0.1mol%,which occurred easily with the increase of acceptor concentration. Itwas explained that such behavior was caused by the variation of thepotential barrier height of grain boundaries for the migration of oxy-gen vacancies as a function of acceptor concentration. In this studysuch dependence of potential barrier height on the acceptor concen-tration will be experimentally identified by TSDC (Thermally Stimu-lated Depolarization Current), voltage contrast SEM, and impedancespectroscopy analysis.

Fundamentals & Characterization: Micro-and Nano- Mechanical Behavior of Low-Dimensional Structures and Materials

Micro- and Nano- Mechanical Behavior of Materials -SimulationRoom: 308Session Chairs: Ya-Pu Zhao, Chinese Academy of Sciences; SusanSinnott, University of Florida

2:00 PMNano- to Micro-scale Deformation During Selectin-MediatedLeukocyte Rolling (Invited)M. R. King*, University of Rochester, USA

The slow rolling motion of cells along the blood vessel wall, medi-ated by the selectin family of proteins, is important in inflamma-tion, stem cell homing, and cancer metastasis. Several different levels

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 147

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania148

of deformation occur during this dynamic process: from viscousmembrane tether extrusion, to cell flattening and enlargement ofthe contact area between cell and wall, to the sequential failure of cy-toskeletal connections and protein-ligand dissociation. All of thesedistinct physical effects have been incorporated into a multiscalemodel of cell adhesion based on the Adhesive Dynamics algorithm.This model has been validated with both flow chamber experimentsand also with intravital microscopy of cell interactions in live ani-mals, to determine the quantitative relationships between cell be-havior, fluid shear stress, and surface receptor density. The interplaybetween nanoscale and microscale cell surface deformation will bepresented, along with the implications of cell-cell hydrodynamiccollisions.

2:20 PMInfluence of Filling Carbon Nanotubes on their MechanicalProperties (Invited)S. B. Sinnott*, University of Florida, USA

The mechanical responses of carbon nanotubes under bending, tensile,compressive, and torsion forces are examined using a multi-scale ap-proach that includes classical molecular dynamics simulations and con-tinuum mechanics models. Several different types of nanotubes areconsidered, including pristine single-walled tubes that are empty, filledwith fullerenes to form peapods, or filled with other nanotubes to formmulti-walled tubes. The effects of system temperature, wall vacancies,and attached functional groups are also considered. The results indicatethat the forces required to deform filled nanotubes are larger than thoseof empty nanotubes. The magnitude of the increase depends on the typeof filling material. The insights and failure criteria developed from thesesimulations can be used to design carbon nanotube-based devices andmaterials, such as nanoelectromechanical systems and nanocomposites,which undergo loading through the external application of forces.

2:40 PMGrowth mechanism and joint structure of ZnO tetrapods:Experiments and DFT simulation (Invited)Y. Zhao*, B. Wang, J. Xie, Q. Yuan, Institute of Mechanics, Chinese Academyof Sciences, China

Regular zinc oxide (ZnO) tetrapods with flat plane have been synthe-sized on Si(100) substrate via chemical vapor deposition (CVD) ap-proach. The x-ray diffraction (XRD) results suggest that thesetetrapods are all single crystals with a wurtzite structure that growalong the (0001) direction and corresponding electron beam backscattered diffraction (EBSD) analysis reveals the crystal orientation ofgrowth and exposed surface. Furthermore we find some ZnOtetrapods with some legs off and the angles between every two legs aremeasured with the aid of scanning electron microscopy (SEM) andimage analysis, which benefits to reveal the structure of ZnOtetrapods joint. The structure model and growth mechanism of ZnOtetrapods are proposed. Besides, the atomic model of the interface wasobtained though density-functional theory (DFT) calculation and theenergy needed to break the twin plane junction was calculated.

3:00 PMIntrinsic Size-Dependent Properties of Nanowires (Invited)T. Zhang*, M. Luo, W. Chan, Hong Kong University of Science andTechnology, China

A prism crystalline nanowire is theoretically treated to be com-posed of a hypothetical nanowire phase, a true two-dimensionalgeometric surface phase, and a true one-dimensional geometricedge phase. The hypothetical nanowire phase could be elasticallydeformed due to relaxation of a free-standing nanowire, withoutany applied load, with respect to its bulk counterpart. The initiallydeformed nanowire phase is taken as reference in the determina-tion of excess surface and edge energies. The edge phase causes the

nominal specific surface energy, surface stress and surface stiffnessto be size-dependent, and the surface phase and the edge phasemake the nominal Young’s modulus size-dependent. The edge andsurface effects are more significant as the cross-sectional area of ananowire becomes smaller. This work was fully supported by anRGC grant HKUST6185/03E from the Hong Kong Research GrantsCouncil.

3:20 PMIndentation deformation of an elastic half space: Effect of thesubsurface crackS. N. Kurapati*, F. Yang, Y. Lu, University of Kentucky, USA

The effect of a subsurface crack on the indentation deformation of anelastic half space by a flat-ended cylindrical indenter was studied,using the finite element simulation. The load-displacement relationwas evaluated, which is a function of the crack size and the distance tothe free surface. Crack opening was observed for some indentation de-formation. Both model I and model II were present due to the contactbetween the indenter and the half-space. The variation of the stress in-tensity factors with the indentation deformation was discussed.

3:40 PMIdentification of elasto-plastic properties of metals using pluralsharp indentersS. Miyazaki*, IHI Corporation, Japan

Several methods for determining material’s elasto-plastic propertiesusing plural indenters have been developed and proposed. Those inden-tation-testing methods are advantageous to obtain material constantsfrom small area. One of the methods including dimensionless functionsexhibits good agreement with macroscopic material properties. Im-provements in accuracy of the method have investigated by operating fi-nite-element simulations and indentation experiments. Some practicalmaterials with different Young’s modulus, yield strengths and workhardening exponents are selected and examined by the indentationmethod.Accuracy of the calculated materials constants is investigated bycomparing with values obtained by macroscopic uni-axial tension tests.

Fundamentals & Characterization: Modelingof Multi-Scale Phenomena in MaterialsProcessing

Microstructure Evolution IVRoom: 306Session Chair: Adrian Catalina, Caterpillar Inc.

2:00 PMPhase-field Model of Phase Transformations and PrecipitateMicrostructure Evolution in Polycrystals (Invited)T. Heo*, L. Chen, The Pennsylvania State University, USA

Precipitation reactions in a polycrystalline material involve thecomplicated coupling among a number of different processes:solute segregation or depletion near grain boundaries, grainboundary migration, precipitate nucleation, growth and coarsen-ing. Therefore, the presence of grain boundaries often leads to in-homogeneous distribution of precipitates, e.g. formation of precip-itate free zones (PFZs), which has important implications to thematerials’ mechanical properties. In this presentation, we will pres-ent phase-field approach to predicting the kinetics of phase trans-formations and microstructure evolution in polycrystals. In partic-ular, we will discuss solute segregation at grain boundaries,isostructural decomposition through either nucleation/growth orspinodal decomposition, as well as precipitation of low-symmetryphases from a high-symmetry matrix in the presence of grainboundaries.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 148

Tues

day

PM

www.matscitech.org 149

2:20 PMCharacterization of interactions between slip-systems and grainboundaries that lead to heterogeneous deformation in CPTiT. R. Bieler*, M. A. Crimp, Y. Yang, L. Wang, Michigan State University, USA;P. Eisenlohr, F. Roters, D. Raabe, Max-Planck-Institut für Eisenforschung,Germany; W. Liu, Argonne National Laboratory, USA; G. E. Ice, Oak RidgeNational Laboratory, USA; D. E. Mason, Albion College, USA

Prior work in identifying conditions for fracture or cavity nucleationin two limited slip system materials suggest that particular kinds of slipinteractions with a grain boundary can weaken it, or highlyanisotropic plastic strains can cause triaxial stresses that favor cavity orcrack nucleation. Using commercial purity titanium as a model mate-rial we are examining how heterogeneous deformation leads to dam-age nucleation, using digital image correlation to measure local strains,orientation imaging microscopy to track grain orientations, electronchanneling contrast imaging to detect dislocation activity, and 3-D x-ray identification of local orientations and orientation gradients, areused to identify local deformation phenomena in the vicinity of grainboundaries. Computational modeling of highly characterized mi-crostructural regions is used in comparison with experiments to eval-uate the accuracy of crystal plasticity finite element models (CP-FEM).

2:40 PMPhase Separation in Anisotropic SystemsW. Feng*, Z. Liu, L. Chen, Penn State Univ., USA

Crystalline systems are intrinsically anisotropic in theirmicro/macroscopic properties. In this presentation, we will describe aphase-field model that incorporates all the important anisotropies insystems with arbitrary crystalline symmetry. These include elastic in-homogeniety and anisotropy, diffusional mobility anisotropy, andnon-dialational transformation strains and its compositional de-pendence. We studied the effect of various anisotropies on the mor-phological evolution during nucleation/growth and spinodal phaseseparation in systems with various crystalline symmetries.

3:00 PMMultiphase Flow Model of Porosity Formation for Casting Processof Aluminum AlloyG. Wang, Y. Rong*, Worcester Polytechnic Institute, USA; S. Xiong, TsinghuaUniversity, China

An integrated model for the casting process of binary aluminum alloyhas been implemented on CFD prediction in this paper. The model,which uses much of the multicomponent multiphase fluid architec-ture as a comprehensive system, involves solid-liquid change, latentheat term, Darcy-based flow in mushy zone, and entrapped air shift.It can predict the formation derived from air entrapment, and themorphology and distribution of porosity. The model is demonstratedon a representative 2-D aluminum shape casting example, in which itproduces reasonable results and describes generation and distribu-tion of porosities with detailed flow structure.

Fundamentals & Characterization: PhaseStability, Diffusion Kinetics and TheirApplications (PSDK-III)

Diffusion Kinetics IIRoom: 302Session Chair: Graeme Murch, The University of Newcastle

2:00 PMSingle-Phase Layer Formation in Two-Phase Diffusion Couples(Invited)X. Pan, N. Zhou, J. E. Morral, Y. Wang*, The Ohio State University, USA

Brittle intermetallic layers formed in the interdiffusion zones of hightemperature coatings and diffusion bonded alloys are detrimental to

coating adherence and the mechanical properties of diffusion bonds.Therefore it is desirable to link the formation of such single-phaselayers to initial alloy compositions and atomic mobilities of the alloy-ing elements. For this purpose phase field simulations were per-formed on diffusion couples prepared from two phase alloys. Variousinitial alloy compositions within the miscibility gap of a prototypeternary system were chosen to form the couples and different atomicmobilities were assumed for the alloying elements. The simulationsshow that a single-phase layer may form at the interface when there isa common matrix phase, while two single-phase layers may formwhen the matrix phase changes at the initial interface. The thicknessof the single-phase layers depends on the difference in alloy composi-tions between the initial alloys and in the atomic mobilities.

2:40 PMThe Proeutectoid Cementite TransformationG. Spanos*, Naval Research Laboratory, USA; M. V. Kral, University ofCanterbury, New Zealand

A comprehensive, critical, and up-to-date overview is presented forthe proeutectoid cementite transformation in steels. Many of thefindings, features, and concepts presented here for this classic phasetransformation in steels serve as a model which may be more broadlyapplicable to many other phase transformations systems. This talkconsiders classic early investigations of cementite morphology inlight of many more recent studies, particularly by the present authors,that provide critical new insight into preoeutectoid cementite mor-phology, crystallography, and formation mechanism(s) in both twoand three dimensions. A number of different orientation relation-ships (ORs) between proeutectoid cementite and austenite are criti-cally evaluated, as are the habit plane, growth direction, and interfa-cial structure of various morphologies of proeutectoid cementite.This talk considers all of these issues in a critical way in order to pres-ent a unified picture of the formation of proeutectoid cementite fromaustenite.

3:00 PMPhase-Field Simulation of Phase Transformations Under aTemperature GradientR. Mohanty*, Y. Sohn, University of Central Florida, USA

The phenomenon known as thermotransport can be observed inmany applications, e.g., interconnects of electronic circuits, metallicnuclear fuel alloys, internally air-cooled gas turbine components, etc.The constituent redistribution due to temperature gradient can causeunwanted phase transformations, and changes in physical and me-chanical properties. A phase field model was devised and employed tostudy the thermotransport in single- and multi-phase binary alloys.Temporal development of microstructure under an applied tempera-ture gradient is simulated using composition and temperature de-pendent mobility and heat of transport. The concentration gradientsdeveloped in single-phase alloys depend on the initial composition,the atomic mobility and the heat of transport of the respective ele-ments. In multi-phase alloys, a formation of dilute solid solutionphases at the cold and hot ends of the alloy was observed.

3:20 PMDiffusion Mobility Descriptions for the CIGS PhotovoltaicSystems (Invited)C. Campbell*, National Institute of Standards and Technology, USA

To reduce the production costs of CIGS (α-CuInxGa1-xSe2) photovoltaiccells, the processing time must be reduced from approximately 30 min-utes to less than 2 minutes. This goal requires finding new reaction path-ways in the Cu-In-Se-Ga system to increase the synthesis rate of the CIGSabsorber material. Using the thermodynamic descriptions developed byAnderson and co-workers, preliminary diffusion mobility descriptionsfor the Cu-In-Se system will be presented. The descriptions are devel-oped based on measured unary, binary and ternary tracer, intrinsic, and

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 149

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania150

chemical diffusion data and experimental HT-XRD data used to deter-mine activation energies based on parabolic growth law kinetics. The dif-fusion mobility descriptions are then used to simulate the Cu-In sel-enization reaction. The results of these simulations will be discussed.

Fundamentals & Characterization: PhaseTransformations and MicrostructuralChanges during Sustained MechanicalForcing

Deformation-induced Microstructural Changes andPhase Transformations IRoom: 310Session Chair: Rainer Hebert, University of Connecticut

2:00 PMNanocrystalline Microstructures by Severe Plastic Deformation,Dynamic Recrystallization, or Recrystallization (Invited)C. C. Koch*, R. O. Scattergood, K. A. Darling, J. E. Semones, North CarolinaState University, USA

Severe plastic deformation, induced by various methods, has producedrefined microstructures. The methods that produce grain sizes down tothe nanoscale (grain size < 100 nm) will be discussed along with thelikely mechanisms responsible in single or multi-component materials.One example of creation of a nanocrystalline microstructure comesfrom dynamic recrystallization during cryomilling of pure Zn powders.Recently, nanocrystalline microstructures have been observed by the ap-parent crystallization of larger nanocrystalline or ultrafine grains. Theseobservations are dependent upon solute additions and the details of themechanism(s) responsible are not yet well understood. This talk will dis-cuss the mechanisms for creation of nanocrystalline microstructures asabove, from both the literature and research in the authors’ laboratory.

2:40 PMDeformation Processing of Nanocrystalline Materials (Invited)G. Wilde*, University of Muenster, Germany

New opportunities for fabricating nanocrystalline materials are basedon repeated cold-rolling and folding. In contrast to the “conven-tional” severe plastic deformation techniques, the process can be ap-plied continuously and allows obtaining pure metals and alloys withextremely small average grain sizes in the range of 10 – 20 nm. More-over, sequentially combining different processing pathways that arebased on continuous strain energy input present new routes fornanostructure formation. In addition, the deformation mechanismsat decreased grain size and the mechanisms that lead to continuedgrain refinement during deformation processing will be highlightedby experimental results from ex-situ and in-situ investigations.Specifically, the existence and the hypothesized role of so-called“non-equilibrium grain boundaries” is addressed experimentally bymeasurements of the grain boundary diffusion. The support of thiswork by DFG within the Forschergruppe “Nanoplasticity” is grate-fully acknowledged.

3:20 PMDeformation induced dislocation storage and microstructureevolution in nanocrystalline metalsS. X. Mao*, U. Pittsburgh, USA

Nanocrystalline materials with small grains have unique deformationmechanisms compared with traditional polycrystalline materials.More recently, the discovery of mechanical grain growth at liquid ni-trogen temperatures showed unique stress induced microstructureevolution. This study focuses on stress-induced grain boundary (GB)dislocation storage and microstructure evolution of grain agglomera-tion / growth in nc materials through in-situ TEM tensile and in-situsynchrotron with hydrostatic pressure up tp 58 GPa. Peak broadening

increases during loading in nc-Ni, indicates high dislocation densitystorage, and no clear grain growth or texturing occurred. The storeddislocations are reversible after unloading, while in course grainedsample, stored dislocations are not reversible.

Fundamentals & Characterization: RecentAdvances in Structural Characterization ofMaterials

Structural Characterization of Materials: PanelDiscussionRoom: 309Session Chairs: Juan Nino, University of Florida; Jacob Jones,University of Florida; Roumiana Petrova, New Jersey Institute ofTechnology

2:00 PMStructural Characterization of Materials - Panel Discussion PanelModerators: Juan C. Nino, Jacob L. Jones and Roumiana PetrovaJ. C. Nino*, University of Florida, USA

This panel discussion is intended to tackle challenging questionsabout structural characterization techniques including current limi-tations, the complementary nature among them, common interpre-tation/analysis problems and mistakes, fostering academic-nationalfacility collaborations, current in-situ capabilities and future develop-ments. This panel session is expected to be an open discussion aboutthe field with questions and interaction from the audience.

Iron & Steel: International Symposium onMaterials Engineering for StructuralApplications

Thermal TreatmentRoom: 328Session Chair: David Milbourn, Vanitec Ltd.

2:00 PMInfluence of Step Down Austempering on the Microstructureand Mechanical Properties of Austempered Ductile Cast IronS. K. Putatunda*, Wayne State University, USA

Austempered Ductile Cast Iron (ADI) has emerged as a very impor-tant engineering material in recent years because of many attractiveproperties such as high strength and ductility ,good fatigue resistanceand high fracture toughness. In this investigation ductile cast ironwas processed by a novel step down austempering process. The effectof this novel process on the microstructure and mechanical proper-ties of ADI has been investigated.The influence of this process on thefracture toughness of ADI was also examined

2:20 PMInfluence of Carbonitriding and Nitriding AtmosphereCompositions on the Corrosion Resistance of 38HMJ and30HN2MFA Constructional Steel GradesT. Zolciak, A. Ciski*, Institute of Precision Mechanics, Poland

In order to test the influence of carbonitriding and nitriding atmos-phere compositions on the corrosion resistance of 38HMJ (DIN41CrAlMo7-10) and 30HN2MFA (~DIN 30CrNiMo8) steels, speci-mens were carbonitrided or nitrided in fluidized bed for 2 and 4hours at 570°C in the following atmospheres: a) ammonia, nitrogenand carbon dioxide, b) ammonia and propane, c) ammonia and en-dogas, d) ammonia, e) ammonia and hydrogen. Results of thethermo-chemical treatments were checked by hardness measure-ments, optical microscopy, electron scanning microscopy and deter-mination of concentration profiles in the case of specimens. Corro-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 150

Tues

day

PM

www.matscitech.org 151

sion resistance was tested with the aid of neutral salt spray. Specimensafter nitriding in ammonia or carbonitriding in ammonia andpropane for 4 hours didn’t reveal signs of corrosion even after exposi-tion time of 1000 hours, while untreated samples corroded after 24 to48 hours.

2:40 PMLaser Heat Treatment and Properties of Surface Hardened SteelC. F. Jenkins, W. R. Hinz, K. J. Imrich*, Savannah River National Laboratory,USA; J. M. Haake, Titanova Inc, USA

Mechanical properties have been measured for the shallow case re-gion of surface hardened 4140 steel. Heat treatment of steel bar wascarried out using HPDDL laser technology. The diode laser was cho-sen for portability and precisely controllable energy transfer oversmall areas. A multiple pass approach on 2 1⁄ 4 in. bar provided 50 Rcat 0.040 in. case depth in 1⁄ 2-in. wide strips, with a tempered zone atthe overlap between passes. Metallographic study and diamond pyra-mid hardness measurements show structural definition for the caseregion. EDM machining was used to generate mini-tensile specimensfrom within the hard zone. Strengths exceeding 250 ksi were devel-oped, corresponding with averaged hardness values >55 Rc. The lasertreatment was applied in situ to rails in a nuclear production facilityat the D.O.E. Savannah River Site. The track supports leaded 90-Tdoors for radiation shielding, so hardening increased wear and gallingresistances on the rolling surface and strength to resist deformation.

3:00 PMLow Temperature Plasma Nitriding of Steel with AdditionalCarburising Gas: Corgon and Propane - ButaneA. P. Zumbilev, I. Zumbilev*, K. Kostov, Technical University of Sofia, PlovdivBranch, Bulgaria

Nitriding and carbonitriding are the basic methods for surfacestrengthening of iron details and instruments made of carbon-ironalloys, in which only nitrogen or simultaneously carbon and nitrogenare introduced into the surface layer. The aim of the present researchproject is to investigate the influence of nitriding and carbonitridingin two treatment media /ammonia - corgon (82% Ar and 18% CO2)and ammonia – propane-butane/ on the surface hardness and totalthickness of the nitrided and carbonitrided layers of 25CrMnSiNi Mosteel. The results show that the chosen gases, which are introduced asindirect rich-of-carbon (carbon containing), can be used in ion car-bonitriding of details and instruments. We can finally conclude thatafter ion carbonitriding of 25CrMnSiNiMo with the two indirect car-bon-carrying gases (corgon – propane-butane), the new layers arewith lower thickness and hardness than the ones in ion nitriding.

3:20 PMCharacterization of Laser-Consolidated 420 Stainless SteelJ. Chen*, L. Xue, S. Wang, National Research Council Canada, Canada

Laser consolidation (LC) is a novel process that produces a net-shapefunctional part layer by layer directly from a CAD model by using alaser beam to melt the injected powder and re-solidifying it on thesubstrate or previous layer. Due to the rapid solidification associatedwith this process, LC materials always show exceptionally fine den-dritic microstructure, resulting in significantly improved mechanicalproperties as compared to the respective cast materials. In this paper,the microstructure of LC 420 stainless steel was investigated. As-con-solidated 420 material is metallurgically sound, free of cracks andporosity. Various post-heat-treatments were investigated and the mi-crostructure changes of the LC SS420 material were examined in de-tails using optical microscopy, SEM/EDS and XRD. The microhard-ness and retained austenite of the LC 420 material were correlated.The effects of the post-heat-treatment on the microstructure, micro-hardness and mechanical properties of LC 420 were also discussed inthe paper.

Iron & Steel: Steel Product Metallurgy andApplications

Microstructure - Property Correlations IIRoom: 330Session Chair: Robert Glodowski, Stratroc

2:00 PMEffects of Heat treatment on the Mechanical Properties of TwoUltra-high Strength Stainless SteelsP. Komolwit*, W. Garrison, Carnegie Mellon University, USA

The two precipitation strengthened Martensitic stainless steels consid-ered have compositions (in wt.%) of 0.005C/14Cr/21Co/5Mo/1.5Ni and0.025C/14Cr/18Co/5Mo/1.5Ni/0.025Ti. When heat treated by austeni-tizing at 1050°C, oil quenching, refrigerating in LN and tempering at550°C they have yield strengths of 1700 MPa and 1630 MPa, respectively.The effects of austenitizing temperature, refrigeration and cooling rateafter austenitizing on tensile properties and Charpy energies have beenevaluated. In addition, the effects of austenitizing at 1050°C and thenreaustenitizing at lower temperatures on mechanical properties havebeen investigated. The purpose of these double austenitizing treatmentswas to refine grain size without reducing toughness. The results will bediscussed in terms of changes in microstructure, primarily grain size andaustenite content, associated with variations in heat treatment.

2:20 PMEfforts Towards Improving Mechanical Characteristics ofMartensitic Stainless SteelsB. L. Choudki*, S. Nair, K. R. Srinivasan, A. Ganguly, Mukand Ltd., India

Mukand has been producing various popular as well as niché grades ofstainless steels for decades and supplying to overseas market successfullyas one of the major suppliers from this part of the world.While austeniticstainless steels are characterized by higher impact strength, in case ofmartensitic stainless steels multiple parameters come in to play, in achiev-ing the higher toughness values. A comprehensive study was conductedto study the effect of variables such as type of quenchant, tempering tem-perature & time, on hardness and microstructural aspects, in order tostandardize the manufacturing process for high toughness martensiticstainless steels. The grades studied were AISI-410/416/420/431. The re-sults obtained are presented and discussed in this paper. Findings showedthat with a quenching agent type B, the desired levels of hardness and me-chanical properties could be achieved at an optimised tempering timeand temperature. Use of these steels in pump shafts, nuts, bolts, etc.

2:40 PMDevelopment of High Strength Formable Grade Steels at SAILA. Deva*, S. Mukhopadhyay, S. Mallik, B. K. Jha, S. K. Chaudhuri, RDCISSAIL, India

In view of challenges from competing materials like aluminium, plas-tics etc., consortiums viz. ULSAB & ULSAB AVC advocated use ofhigh strength steels to make more fuel efficient and safer vehicles.Inline with this,high strength hot rolled(YS:460 MPa min) & coldrolled(YS: 260&400 MPa min) steels with improved forming capacityhave been developed at Steel Authority of India Ltd.Innovative alloyshave been designed and processed by adhering to optimised parame-ters evolved through thermo mechanical simulation studies usingGleeble 3500 C system.Steels with Nb(0.01-0.02wt%) & Si(0.25-0.30wt%) content showed higher elongation(38%),higher hole ex-pansion (45%) and lower YS/UTS ratio(0.86) whereas steels withNb(0.05-0.06wt%) & Si(<0.05wt%) content manifested lower elon-gation (34%),lower hole expansion (34%) & higher YS/UTS ratio(0.94).Improved formability properties of high Si containing steelsare attributed to scavenging effect leading to formation of cleanerferrite.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 151

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania152

3:00 PMCorrelation between Deformation Behavior and Microstructuresof a Fe-28Mn-9Al-0.8C SteelJ. Yoo, K. Park*, Hanbat National University, South Korea

Austenitic steels with the high Mn content are attractive as automo-tive sheet materials due to their good strain hardenability. The twininduced plasticity (TWIP) steel is one of the representatives. Recently,a new class of steel having high Mn, Al and C is being developed andis reported to exhibit the mechanical properties better than the TWIPsteel. Since the Al addition into high Mn austenite matrix increasesthe austenite stability and stacking fault energy (SFE), the deforma-tion mechanisms of this steel class are expected to differ from those ofthe TWIP steel. In this study, the room temperature deformation be-havior of Fe-28Mn-9Al-0.8C steel, one of the high Mn-Al-C steels,was examined to find the governing deformation mechanisms associ-ated with SFE. The steel showed an excellent combination of strengthand ductility over 80,000 MPa�% and the microband induced plas-ticity was found to dominate the overall plastic deformation.

3:20 PMEdge Fracture of Dual Phase Steel in Hole ExpansionX. Wu*, H. Hamed Bahmanpour, Wayne State University, USA; M. F. Shi,United States Steel, USA

Advanced dual phase (DP) steel is used for autobody structures. Dur-ing sheet stamping the steel is prone to edge cracking, which reducesthe maximum strain, and a reliable prediction methodology isneeded. In this paper, the factors affecting edge cracking are studiedby hole expansion tests and by microstructural and mechanicalanalyses. The mechamically trimmed edge before flanging is charac-terized first, and a comparison with mild steel is made. During flang-ing these edge features and interior dual phase microstructures arefound to have significant impact to crack initiation and propagation.The methodology to predict forming limit of DP steel is discussed.

Materials & Systems: Advances in Biomedicaland Biomimetic Materials

Advanced BiomaterialsRoom: 333Session Chair: Devesh Misra, University of Louisiana

2:00 PMImprovement in Mechanical Functionality of Porous Titanium byBiopolymer Filling (Invited)M. Niinomi*, M. Nakai, T. Akahori, H. Yamanoi, IMR, Tohoku University,Japan; S. Itsuno, N. Haraguchi, Toyohashi University of Technology, Japan; Y.Itoh, Hamamatsu Industrial Research Institute of Shizuoka Prefecture, Japan;T. Ogasawara, T. Onishi, Osaka Titanium Technologies Co., Ltd., Japan; T.Shindoho, ECRI, Tohoku University, Japan

A lot of beta-type titanium alloys with low Young’s modulus havebeen developed from the viewpoint of inhibiting bone absorption.Their Young’s moduli are still higher than that of bone. Porous tita-nium is advantageous for achieving Young’s modulus equal to that ofbone with keeping high biocompatibility. On the other hand, me-chanical strength of porous titanium is poor. It is effective to fillporous titanium with biopolymer to keep its mechanical strengthhigh. Therefore, mechanical properties of porous titanium made oftitanium powder with different diameters filled with PMMA (poly-methylmethacrylate) were investigated in this study. Tensile strengthof porous titanium filled with PMMA exhibits higher tensile strengthcomparing with that of porous titanium while Young’s moduli ofboth specimens are nearly equal each other. Silan coupling treatmentis effective to increase tensile strength further with keeping Young’smodulus equal to that of the case without silan coupling treatment.

2:20 PMPorous NiTi with Superelastic or Shape-Memory PropertiesA. Bansiddhi, D. Dunand*, Northwestern University, USA

NiTi with 50-70% porosity is fabricated by sintering of prealloyedNiTi powders with temporary NaCl space-holders. The pore fraction,size, shape and connectivity are controllable through the initial vol-ume fraction and geometry of the space-holders. The NiTi foams ex-hibit superelasticity or shape-memory properties, depending onexact composition. High compressive yield strength with very lowstiffness (<20 GPa) and large recovery strain are observed.

2:40 PMTunable Nanoparticles: Drug Delivery and Cellular Uptake(Invited)D. K. Misra*, University of Louisiana at Lafayette, USA

The primary challenge in the delivery of a drug to a tumor site is totarget the anticancer drug specifically into and around tumors at con-centrations that will decrease their growth and/or viability. Excellentvehicles for targeted drug delivery are magnetic nanocarriers. Thepresentation describes important aspects concerning the fabricationof a novel temperature and pH-responsive magnetic nanocarrier thatcombines tumor targeting, carrier monitoring, and controlled drugrelease, with particular emphasis on physico-chemical properties ofthe nanocarrier. The magnetite containing nanoparticles offer thepossibility of imaging the delivery process by magnetic resonance im-aging (MRI) and the ability to enhance drug efficacy by heat that re-sults from the application of an external magnetic field. This localizedand targeted heat, in conjunction with localized drug release aids inthe destruction of cancer cells. Thus, the combination of bothchemotherapy and heat can be used for tumor therapy.

3:00 PMSelf-assembled Lipid-nanocrystal Vesicle Hybrids as TheranosticDevices for CancerW. T. Al-Jamal*, K. T. Al-Jamal, K. Kostarelos, School of Pharmacy, UnitedKingdom

Nanocrystals are novel nanomaterials that have been used to labelcells in vitro and tissues in vivo. Seeking novel multimodal therapeu-tics, we have demonstrated that a variety of nanocrystals and lipidcomponents can self-assemble into nanoscale, lipid-nanocrystal hy-brids which were successfully used to label cells in vitro and tumorsvivo. Moreover, we assessed the fate of the lipid-nanocrystal hybridsin animal models after local and systemic administration. Tissuebiodistribution, affinity and blood pharmacokinetic parameters werefound to be dependent on multiple factors, primarily governed by thenanocrystal characteristics and the lipid coat components. By varyingsuch parameters, we could develop and evaluate pharmacologicallyvarious lipid-nanocrystal hybrid systems of versatile features. Thedata obtained indicates that such lipid-nanocrystal hybrids can beconsidered as effective, biocompatible platforms for combinatory di-agnostic and therapeutic biomedical applications.

3:20 PMNanitechnology in Drug DeliveryE. p. Yedidi*, Osmania University College of Technology, India

The application of nanotechnology could impact,diagnosis monitor-ing and treatment of diseases as wellas control and understanding ofbiological systems.naoparticles r prefarable to microparticlesas theycannot be blocked at the microvasculature.thay can be taken up di-rectly by the cells through natural means such as endocytosis.in gen-eral targeted nanoparticles comprise drug,encapsulating material andthe surface coating.top down nano fabrication n microfabrication ap-proaches based on integrated circiut processing may be used to fabri-cate controlled release drug delivery devices.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 152

Tues

day

PM

www.matscitech.org 153

3:40 PMNanotechnology in MedicineC. Uzomah*, Institute of Management and Technology, Nigeria

There is increasing anticipation that nanotechnology, as applied tomedicine, will bring significant advances in the diagnosis and treat-ment of disease. This has prompted many government and fundingagencies to strategically review the field, and the primary objectivehave been to ascertain current status, to establish a common termi-nology, to assess potential benefits and risks to establish priorities forfuture funding initiatives. Although not widely appreciated, progressin the development of nano-sized hybrid therapeutics and nanosizeddrug delivery system over the past decade has been remarked. Rou-tine clinical use and clinical development of nano-sized drug deliveryvectors including liposomes, antibody conjugates, nanoparticles andpolymer therapeutics as anticancer treatment is growing rapidly. In-deed, there is widesparead anticipation that application of suchnanoatechnologies in medcine will bring the paradigm shift neededto improve both cancer diagnosis and therapy.

4:00 PMSuperparamagnetic, Flame Synthesized Iron Oxide Nanoparticlesfor Biomedical ApplicationsK. Buyukhatipoglu*, A. Morss Clyne, T. A. Miller, Drexel University, USA

A heterogenous mixture of hematite and magnetite nanoparticleswith two different size modes, including non-agglomerated particlesof 50-60 nm diameter and smaller agglomerated particles with 10-15nm diameter have been synthesized using a flame synthesis method.Interaction of these nanoparticles with porcine aortic endothelialcells has been investigated and the results have been compared tothose obtained using commercially available iron oxide nanoparti-cles. Nanoparticle biocompatibility was assessed by incubating flamesynthesized and commercially available iron oxide nanoparticles withendothelial cells for 24 hours. Trypan blue, alamar blue andLive/Dead cell assays showed no significant toxicity difference be-tween flame synthesized and commercially available nanoparticles.Endothelial cells imaged by ESEM and confirmed by EDS demon-strated that uncoated flame synthesized nanoparticles are ingestedinto cells in a similar manner to commercially available nanoparticles.

Materials & Systems: Advances inCharacterization and Modeling ofCementitious Materials

Modified Fresh or Hardened Properties andNontraditional Applications of Cement-basedMaterials IIRoom: 331Session Chair: Joe Biernacki, Tennessee Technological University

2:00 PMChanges in the dynamic mechanical response of C-S-H on theremoval of waterR. Alizadeh*, J. J. Beaudoin, L. Raki, National Research Council Canada,Canada

Calcium Silicate Hydrate (C-S-H) was synthesized at various stoi-chiometric ratios of CaO to SiO2. Compacts of the C-S-H powderswere prepared at various porosity levels and conditioned at11%RH. The storage modulus (E’) and the loss modulus (E”) weremeasured for each sample after incremental removal of the waterusing vacuum or a combination of vacuum and heat at tempera-tures ranging from 30 °C to 110 °C. The results were interpreted interms of the corresponding changes in the basal spacing and silicatepolymerization of the C-S-H (determined using X-ray diffractionand NMR techniques) upon the removal of adsorbed and interlayer

water. A mechanistic model was proposed for explaining the de-pendence of E’ and E” on the removal of water. The dynamic me-chanical properties of cement paste (w/c=0.4) and porous glasssamples subjected to a similar drying procedure were investigatedfor comparison.

2:20 PMNovel Chemical-Thermal Treatment of Rice Husk Ash To EnhanceProperties of High Performance ConcreteA. Salas*, S. Delvasto, R. Mejía de Gutierrez, Universidad del Valle, Colombia;D. Lange, University of Illinois, USA

This paper reports on a new chemical-thermal treatment that im-proves the effectiveness of the RHA for use in high performanceconcrete (HPC). The new material is produced using a chemical-thermal attack as a treatment to the rice husk before it is burned.The resulting ash (ChRHA) was compared to ash produced byconventional incineration (TRHA). The fresh and hardened prop-erties of HPC made with different percentages of these RHAs werestudied. The hardened concrete testing included the determinationof the modulus of elasticity and the compressive and flexural prop-erties. It was found that digestive chemical treatment before burn-ing produced an RHA with properties comparable to silica fume.The ChRHA was highly amorphous, white in color, presentedhigher specific surface area and greater pozzolanic activity. It wasshown that ChRHA and TRHA were effective supplementary ce-menting materials, although concrete mixes required higherdosages of superplasticizer.

2:40 PMEffect of Chemical-Thermal Treatment of Rice Husk Ash onhydration Characteristics of ordinary Portland CementA. Salas*, S. Delvasto, R. Mejía de Gutierrez, Universidad del Valle, Colombia;L. J. Struble, University of Illinois, USA

The effect of highly active rice husk ash, produced using a chemical-thermal attack as a treatment to the rice husk before it is burned onthe hydration of ordinary Portland Cement (OPC) has been studied.Ordinary Portland Cement pastes with 0, 5, 10 and 15% wt replace-ment of mineral admixtures were examined separately at 28, 56 and90 days of hydration by X-ray diffraction, Scanning Electron Mi-croscopy and Mercury Intrusion Porosimetry. The hydration prod-ucts in the OPC+Untreated Rice husk ash, OPC+Treated Rice huskash, and OPC+Silica Fume systems were found to be similar to that ofpure OPC, except with the low quantity of Ca(OH)2. Comparison ofthe results also showed that the incorporation of chemically treatedRice Husk Ash has a similar effect than silica fume on the hydratedpastes by refining the pore structure.

3:00 PMThe Effect of Humidity on the Mechanical Properties of GypsumZ. Chen*, K. T. Faber, Northwestern University, USA

Gypsum products are made of interlocking needle-like crystalsbonded at their contact points. The mechanical properties of this cel-lular solid are controlled by the intercrystalline interaction and theinterlocking structure; they are also very sensitive to moisture contentin the environment. In this study, the strength and fracture toughnessof gypsum were investigated in a modified Brazilian test and four-point bend tests, respectively. Samples were exposed to dry (~18%relative humidity) and humid (>90% RH) conditions for varioustimes before they were tested in-situ. It was found the strength re-tained after long exposure at high humidity was related to the relativedensity of the sample. Similar degradation of the fracture toughnesswas observed in humid environments, although the samples exhib-ited a resistance to fast crack propagation when tested at extremelyhigh humidity. The phenomena observed at high relative humidityare attributed to drastic changes in intercrystalline interactions.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 153

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania154

ACerS Cements Division Della Roy LectureRoom: 301Session Chair: Zachary Grasley, Texas A&M University

4:00 PMUnderstanding Frost Damage (Invited)G. W. Scherer*, Princeton University, USA

Frost damage to concrete is a serious problem that has been inten-sively studied for decades, yet the mechanisms are not clearly under-stood. Salt scaling seems to be an example of “glue spalling”, where acrack in the surface layer (ice) penetrates slightly into the substrate(concrete) and removes a chip. The phenomenology of scaling, in-cluding the effect of solute concentration, air entrainment, tempera-ture cycle, and thickness of the ice layer can all be explained using thismodel. Internal frost damage is more complicated, because severalmechanisms may be involved.

Materials & Systems: Amorphous Materials:Common Issues within Science andTechnology

Metallic GlassesRoom: 334Session Chair: Steve Feller, Coe College

2:00 PMEffects of Test Temperature and Composition on MechanicalProperties of Al-Based Amorphous alloysC. Huang*, J. J. Lewandowski, Case Western Reserve University, USA

The deformation behavior of Al-based amorphous alloys was character-ized. A series of Al-based ribbons were produced via the melt spinningtechnique. High temperature microhardness indentation and uniaxialtensile tests were conducted over a range of temperatures to investigatethe effects of changes in test temperature and chemical composition onthe mechanical properties of these ribbons. Furthermore, microstructualevolution and fracture surfaces were analyzed by a variety of analyticaltechniques, including X-ray diffraction, differential scanning calorime-try, laser confocal microscopy, and scanning electron microscopy

2:20 PMEffects of Thermal Exposure & Test Temperature on StructureEvolution & Viscosity of an Fe-Based Metallic GlassA. Shamimi Nouri*, Case Western Reserve University, USA; Y. Liu, Wayne StateUniversity, USA; J. J. Lewandowski, Case Western Reserve University, USA

High temperature microhardness testing on fully amorphousFe48Mo14Cr15Y2C15B6 was performed in order to determine thebehavior and structure evolution of this Fe-BMG under a variety oftest conditions. The effects of changes in test temperature on thehardness/strength were determined over the temperature range from25°C to 620°C. Although high (>12GPa) hardness was exhibited at25°C, significant hardness reductions were exhibited near Tg. In ad-dition, the effect of exposure time(≤5 hrs) at elevated temperature onthe evolution of hardness/strength was evaluated for selected temper-atures. The microhardness results were complemented with XRD,conventional TEM and an in-situ heating TEM study in order to eval-uate any structural evolution that could explain the large differencesin hardness evolution with time at different temperatures. The resultsare analyzed by considering the effects of structure evolution on theviscosity of the glass at temperatures near Tg.

2:40 PMEffects of Superimposed Pressure on Flow of Metallic GlassesJ. Caris*, J. J. Lewandowski, Case Western Reserve University, USA

The processing and mechanical behavior of many important materi-als is affected by imposed stress state. One convenient way to assess

the effects of changes in stress state on flow/fracture is to conduct ex-periments with superimposed hydrostatic pressure. A recent reviewof the literature reveals few studies of this nature on amorphous met-als (i.e. bulk metallic glasses). This presentation will summarize all ofthe experimental data obtained to date at CWRU on a variety of dif-ferent bulk metallic glasses. The effects of superimposed pressure onthe flow will be summarized and compared to the pressure sensitivityof various elastic constants for bulk metallic glasses. In particular, theeffects of superimposed pressure on the bulk modulus and shearmodulus of bulk metallic glasses will be presented and compared tothe experimental observations of superimposed pressure on the flowcharacteristics, in the manner previously conducted by Spitzig andRichmond.

3:00 PMExperiments on High Strain-Rate Loading of a Zr-based BulkMetallic GlassG. Sunny*, V. Prakash, J. Lewandowski, Case Western Reserve University, USA

Liquidmetal-1 (LM-1) is a Zr-based bulk metallic glass with both de-sirable processing (1 K/s critical cooling rate) and mechanical proper-ties (2 GPa quasi-static yield strength, 2% elastic strain). The Split-Hopkinson Pressure Bar (SHPB) was employed to investigate thedynamic compressive behavior of LM-1. Modified maraging steel in-serts were utilized for the SHPB to reduce stress concentration effectson LM-1 behavior, and strain gages were placed directly on specimensduring testing to compensate for the deformation of the modified in-serts. To examine the macroscopic fracture behavior of LM-1, anultra high-speed camera was employed to perform in-situ video ofthe deformation and failure process of LM-1 at 200,000 frames/sec.In addition, scanning electron microscopy was performed to investi-gate effects of L/D ratio and annealing on failure surface features.

3:20 PMObservation of Dislocation-Type Defects in Amorphous AlloysM. Finkel*, DAATH-Scientific Center, USA; L. B. Zuev, V. I. Danilov, Instituteof Strength Physics and Materials Science, Russian Federation

Metallography methods have been used to reveal dislocation-type de-fects in an amorphous structure. Pile-ups of defects with a popula-tion density of up to 1012 m-2 have been found in melt-spun amor-phous alloys of different systems. In as-cast metallic glasses, thepile-ups consist of defect chains having a length of up to several mi-crometers with an estimated defect cross-section diameter of about10-9-10-8m. The reordering of defects due to structural relaxation,plastic deformation and fracture of material has been found. Patternsof etching figures, similar to those observed for dislocations in crys-tals, such as straight chains of etching pits, are obtained. Based on theparticularities of etching patterns, it is suggested that these defectscan be best described in terms of screw dislocations. The initial defectpile-ups formation is partially ascribed to thermal stresses in the so-lidified ribbon. Four stages mechanism of plastic deformation associ-ated with such defects is proposed.

3:40 PMShear Band Evolution under Dynamic Loading in Bulk MetallicGlassesG. Subhash*, University of Florida, USA; H. Zhang, REL Inc., USA; S. Maiti,Michigan Technological University, USA

Shear band spacing and their patterns under dynamic (100 microsec-ond) indentation loads in Zr-based bulk metallic glasses have beenfound to vary with position and local strain rate in the indented re-gion. To investigate the dependence of shear band evolution charac-teristics on local strain rate and normal stress, a thermo-mechanicalmodel based on momentum diffusion is proposed. The model ac-counts for the normal stress dependence of yield stress, the free vol-ume theory and the associated viscosity change within the shear bandregion. It is found that thermal effects play a minor role when thecritical shear displacement is small (e.g., nanoindentation) but be-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 154

Tues

day

PM

www.matscitech.org 155

come significant when the shear displacement accumulated in a shearband is large (as in uniaxial compression and in indentations). Thenormal stress plays a crucial role in the deformation behavior ofBMGs by not only decreasing the time for shear band formation butalso increasing the temperature rise significantly.

4:00 PMCrystallization Kinetics and Thermal Stability of Cu-Zramorphous alloysI. Kalay*, M. J. Kramer, R. E. Napolitano, Ames Laboratory/Iowa StateUniversity, USA

The Cu-Zr binary system is well known for its high glass forming abil-ity, metastable phase formation, and complex devitrification behavior.In the work presented here, the crystallization kinetics and thermalstability of the Cu64.5Zr35.5 and Cu50Zr50 amorphous alloys wereinvestigated using differential scanning calorimeter (DSC) and in situhigh energy synchrotron X-ray diffraction (HEXRD) in isochronaland isothermal annealing conditions. The isochronal devitrificationphase transformation paths were determined using high temperaturein situ experiments. The activation energies of crystallization andglass transition were calculated. Isothermal curves for “crystallizedphase fraction” were determined from DSC and HEXRD experimentsand were found to be in good agreement. The kinetics mechanisms atvarious stages of crystallization was modeled using Johnson-Mehl-Avrami (JMA) analysis and corresponding structural changes weredetermined using high temperature isothermal HEXRD.

4:20 PMStudy on Preparation and Properties of Glass Ceramic on MetallicSupportsW. Han*, X. Niu, J. Wang, G. Liu, Jilin University, China

In order to solve the difficulties of washcoat deposited on metallic sup-ports and the problem of coating adhesion during service, inorganicand nonmetallic coating has become the key of research in recent years.The glass ceramic which is made by sol-gel method after the pre-treatedprocess of metallic supports had solved well the problem of peeling dueto difference in thermal expansion coefficients between the metallicsupports and coating. The microstructure and surface character of themetallic supports and glass ceramic were investigated by XRD, SEM,BET and ultrasonic vibration. It was found that the glass ceramic hasbetter ductility under heating, resisted impact strength, excellent chem-ical stability and thermal stability. The glass ceramic can provide largerspecific surface areas and increase the corrosion resistance of metallicsupports. The glass ceramic with the superior properties will have awide prospect of application for a variety of automotive catalyst.

Materials & Systems: Enabling SurfaceCoating Systems: Science and Technology

Thermal Barrier Coatings IIRoom: 335Session Chairs: Yutaka Kagawa, University of Tokyo; Daniel Mumm,University of California, Irvine

2:00 PMMicrostructural Change of TGO in EB-PVD TBC System: Effect ofThermal and Mechanical Loading History (Invited)M. Hasegawa*, Yokohama National University, Japan

During the service of gas turbine engine, various combinations ofthermal and mechanical loadings are applied in electron beam yttria(8mass%) stabilized zirconia thermal barrier coating systems (EB-PVD TBCs). Change of TGO formation was found in different com-bination of thermal and mechanical loading. Evolution of mi-crostructure on the EB-PVD TBCs under various thermal andmechanical loading conditions is described. Morphology and crystalorientation distribution of TGO changed depending on experimental

conditions. Rumpling behavior of TGO was found to depend on theloading direction under thermo-mechanical loading conditions.Change of orientation distribution of TGO was observed in differentmechanical load conditions applied in TBCs. The relationship be-tween crystal orientation distribution, morphology and microstruc-ture change of TGO will be presented with an emphasis on the role ofthe applied load.

2:40 PMHf Effects on the Oxidation Behavior of Pt-Modified γγ-Ni+γγ′′-Ni3Al-Based Alloys and CoatingsN. Mu*, B. M. Gleeson, University of Pittsburgh, USA

The influence of Hf addition on the high-temperature growth behav-ior of alumina-rich scales formed on Pt-modified γ-Ni+γ′-Ni3Al-based alloys at 1150°C was investigated. It was found that the Al2O3scale grew at a subparabolic growth rate on alloys doped with opti-mum Hf levels; while excess Hf led to more rapid parabolic-likegrowth kinetics of a heterogeneous scale of Al2O3 and HfO2. Mi-crostructural analysis revealed that Hf tends to segregated into theAl2O3 grain boundaries and the resulting grain size was smaller thanwhat was formed on the Hf-free alloys. Further, it was found that Hfadditions tend to delay the θ-to-α-Al2O3 transformation duringearly-stage oxidation. Pt+Hf-modified γ+γ′ coatings were developedon the basis of bulk-alloy study and deposited by a pack cementationprocess. The cyclic oxidation of the Pt+Hf-modified γ+γ′ coatingswill be assessed and compared to current state-of-the-art β-NiAl-based coatings.

3:00 PMOxidation of single phase NiCrAl(Y) bond coat alloys: stress,microstructure and the oxide/alloy interfaceL. Hu*, D. Hovis, CWRU, USA; B. Veal, A. Paulikas, Argonne NationalLaboratory, USA; A. Heuer, CWRU, USA

NiCrAlY alloys are commonly used as bond coats in Thermal BarrierCoating systems. During high temperature service, oxidation of thebond coat alloy leads to formation of the so-called thermally grownoxide (TGO). The stresses induced by such oxidation, the microstruc-ture of the TGO and the structure of the oxide/alloy interface are im-portant factors which can lead to premature failure of the thermalprotection system. Single phase β-NiCrAl(Y) and γ-NiCrAl(Y) bondcoat alloys have been studied in this work. For β-NiCrAl(Y), voids arefound either at the oxide/alloy interface or inside of the TGO; for γ-NiCrAl(Y), a layered TGO scale is formed. Such oxidation behavior isclosely related to the properties of the oxide/alloy interface. The effectof the interface on stress and microstructure of the TGO will also bediscussed.

3:20 PMMicrostructural Evolution and Failure Characteristics of aNiCoCrAlY Bond Coat in “hot spot” Cyclic OxidationF. Cao*, Los Alamos National Lab, USA; B. Tryon, Pratt and Whitney, , USA;C. J. Torbet, T. M. Pollock, University of Michigan, USA

The evolution of the microstructure of a NiCoCrAlY bond coat (BC)on a single crystal superalloy substrate without a ceramic top layer wasinvestigated in a new “hot spot” apparatus with a temperature gradi-ent along the longitudinal direction of cylindrical bar specimens.Local spallation events were observed at the “hottest spot” of the spec-imens after cyclic oxidation at 1050 °C. The spallation events occurredat room temperature and the fractional area spalled at the hot spot in-creased with longer hold time at room temperature. Features of thesurface morphology of the failed bond coat and also the cross-sectionmicrostructures have been characterized, including morphologicalimperfections in the thermally grown oxide. A continuous gammalayer was formed at both the TGO/BC and the BC/substrate interfaceand the variation of its thickness with oxidation temperatures and itspossible effect on the TGO/BC interface toughness is discussed.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 155

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania156

3:40 PMEffect of Yttrium on the Microstructure and Phase Transformationin Cryomilled HVOF NiCrAlY Bond CoatK. Ma*, J. M. Schoenung, University of California - Davis, USA

The addition of yttrium into NiCrAlY coatings has been reported toimprove the adhesion of the alumina and retard its tendency to spalleven though the amount of yttrium in the alloy is small. To furtherinvestigate the effects of yttrium, cryomilled NiCrAlY and NiCrAl, inthe form of both powder and HVOF (high velocity oxygen fuel) coat-ings, were examined comparatively for chemical composition, mi-crostructure features and phase transformation kinetics. SEM andEDX were used to study the microstructure and the chemical compo-sition in different phases. TEM was applied to look for nano-scale yt-trium oxide dispersoids and intermetallics such as Ni-Y. In addition,the phase change γ + β <- - - > γ’+ α has been observed in theNiCrAlY system. DTA (differential thermal analysis) was carried outto investigate the influence of yttrium on the phase transformationtemperature and the enthalpy of the reaction.

4:00 PMPt-modified Aluminide Coatings Developed with an IndustrialVapor Phase Coating ProcessY. Wang*, SIFCO Minneapolis, USA

Pt-modified aluminide coatings were developed by electroplating athin layer of Pt followed by an industrial vapor phase aluminizingprocess on Ni-base superalloys. The coated samples were analyzed byusing optical microscope and scanning microscope. Pt-modified alu-minide coatings produced by using 44Al-56Cr, 30Al-70Cr, or 15Al-85Cr nuggets were compared; in addition, Pt-modified aluminidecoatings were also compared with simple aluminide coatings (with-out Pt) formed on the same substrate by using the same vapor phasecoating process.

Materials & Systems: InternationalSymposium on Innovative Processing andSynthesis of Ceramics, Glasses andComposites

Combustion Synthesis/Reaction FormingRoom: 336Session Chair: Holly Shulman, Ceralink Inc.

2:00 PMSelf-Propagating High Temperature Synthesis (SHS) ReactionsUtilizing Lunar Regolith SimulantE. J. Faierson*, K. V. Logan, M. P. Hunt, Virginia Polytechnic Institute andState University-National Institute of Aerospace, USA; B. K. Stewart,Virginia Polytechnic Institute and State University-NASA Langley ResearchCenter, USA

The colonization of the Moon and Mars will require the use of in-situresources for habitat construction and mining operations. A methodhas been discovered which converts a mixture of lunar regolith simu-lant and aluminum into a dense ceramic material. This is accom-plished by heating a volume of the mixture to the ignition tempera-ture, which initiates a SHS reaction. The reaction product takes theshape of the reaction crucible, and a large amount of excess heat isproduced from the reaction. X-ray diffraction peaks which matchthose of elemental Si, Fe, and possibly Ti have been found within thediffraction pattern of the ceramic product. Enthalpies of reactionwith aluminum were calculated for the compounds derived frombulk composition analysis of the simulant. It was determined that thereduction of Fe2O3 and FeO are the most thermodynamically favor-able reactions. It is theorized that the melting of aluminum (660°C)initiates the reduction of Fe, Si, and Ti oxides.

2:20 PMPreparation of La1-xSrxMnO3 by Self-Propagating HighTemperature SynthesisS. Lin*, J. Selig, Lamar University, USA

La1-xSrxMnO3, cathode materials for solid oxide fuel cells were pre-pared by Self-propagating High-temperature Synthesis (SHS) fromvarious reactant mixtures. Thermal analyses (TG/DSC) were used tostudy the reactions between reactant powders at elevated tempera-tures. Temperature history and product compositions at different re-action stages were measured. Using these results, a reaction mecha-nism was proposed to explain the reaction network and the activationenergies for different starting mixtures were calculated. A finite ele-ment model of the SHS of La1-xSrxMnO3 powders was developedbased upon the experimental data and data from literatures. Thismodel was used to modify reaction conditions for SHS of La1-xS-rxMnO3 . X-ray diffraction and SEM analysis were conducted in orderto compare conventionally synthesized powders with powders synthe-sized by SHS.

2:40 PMDetermining the effect of composition on the melting of Al2O3-TiB2 compositesS. Holt*, K. V. Logan, Virginia Tech, USA

Al2O3-TiB2 composites are under study for use in high perform-ance applications such as ceramic armor and aerospace disc brakes.These composites can be produced using Self-Propagating HighTemperature Synthesis (SHS) reactions which can significantly re-duce the composite production cost. Finding a composition in thissystem with a low melting point would allow for processing ofthese composites at a reduced energy cost. This work examines themelting point of several compositions in the Al2O3-TiB2 binarysystem.

3:00 PMSynthesis of Uranium Nitride at Low Temperatures via ReactiveBall-MillingB. J. Jaques*, B. M. Marx, D. D. Osterberg, M. F. Hurley, D. P. Butt, Boise StateUniversity, USA

The development of a closed, low temperature synthesis route toproduce nitrides will have a profound positive effect on their po-tential future uses in nuclear reactors. Nitrides have been identifiedas possible fuel materials for several Generation IV reactor designsand are favored over other fuel forms due to a combination ofhigher actinide loadings, higher thermal conductivities, and lowerthermal expansion coefficients. Using pure metal, similar to whatis produced via pyroprocessing techniques, as a starting materialfor any synthesis technique reduces the amount of steps and han-dling concerns required to produce a useful fuel form. A high en-ergy, low-temperature, ball milling route was used to produce ura-nium nitride. 99.78% pure U metal particles (~100 μm) were ballmilled in a 400 kPa N2 atmosphere for 24 hours at ambient tem-perature to yield phase pure U2N3 powder as confirmed by XRDanalysis. The median particle size was measured to be approxi-mately 6 μm.

3:20 PMBulk Nanostructured Titanium Boride (TiB) Ceramic: Synthesisand PropertiesS. Madtha, K. Chandran*, University of Utah, USA

Successful synthesis of bulk nanostructured titanium boride (TiB)ceramic material is reported. This fully dense ceramic is made of ex-tremely fine TiB whiskers, with their diameters in nanoscale range(50-500 nanometers). The whiskers, grown in-situ at temperaturesless than 1400C, are interconnected to achieve this densely packed

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 156

Tues

day

PM

www.matscitech.org 157

configuration. Unlike its close cousin, the titanium diboride, thenanostructured TiB material can be made at much lower tempera-tures, to any size and to full density, using conventional ceramic pro-cessing methods. Some of the best properties achieved are: 370-425GPa tensile elastic modulus, about 800 MPa flexure strength, about16 GPa Vickers hardness and about 6 MPa-sqrt(m) indentation frac-ture toughness. Comparison with a commercially available silicon ni-tride ceramic reveals that the properties of this nanostructured mate-rial are on par with that of the silicon nitride. The material is quitepromising for diverse commercial applications.

3:40 PMNanoporous Glass-Ceramic MembranesM. E. Miller, S. T. Misture*, NYSCC @ Alfred University, USA

The feasibility of producing nanoporous glass-ceramics by a novelmethod is presented. The process involves heating nickel containingcordierite glasses, xNiO (2-x)MgO 2Al2O3 5SiO2 for 0≤x≤1 to crystal-lize the Ni-bearing phases spinel and cordierite. A second heat treat-ment in a hydrogen atmosphere reduces the Ni2+ to the metallic state.Nanopores are created in the crystalline phases by reducing Ni2+

while maintaining the Al-O-Si framework. Evenly dispersed nickelmetal colloids cover the surface of the glass following exposure to hy-drogen. Rietveld refinement of X-ray diffraction data and permeabil-ity measurements are used to characterize the membranes in the con-text of gas separation.

Nanotechnology: Controlled Processing ofNanoparticle Structures and Composites

Suspension Control and Nanoparticle AssemblyRoom: 408Session Chair: Erica Corral, University of Arizona

2:00 PMHierarchical Assembly of Hybrid Nanoapatites: Implications forOral Drug Delivery and Implant-biological InterfacesR. K. Kasinath*, A. Brazier, Montana Tech of the University of Montana,USA; K. H. Prakash, The University of Queensland,, Australia; L. Gower,University of Florida, USA

This work describes the hierarchical structuring of hybrid nano-hy-droxyapatite (nHA) mediated by chitosan. Trace amount of chitosan,present during solution crystallization, modulated nHA growth andpromoted assembled chains of spheroidal nHA with a narrow size dis-tribution. After solvent extraction, scanning electron microscopy offilms indicated assembly at multiple length scales. Below 50 nm, order-ing of nHA particles on self-assembled fibrils of chitosan, and between500-2000 nm a higher order structure resembling a nano-porous inter-penetrating composite of HA and chitosan was observed. X-ray diffrac-tion and Rietveld analysis revealed size and shape modulated crystallites.The film cross-section revealed structural and compositional gradingwith mainly chitosan on one surface and nHA on the other. This impliedthat such hierarchically structured hybrid nanostructures can be utilizedfor novel drug delivery devices and implant-biological interfaces.

2:20 PMThe structure of nanoparticulate aggregates of titania as afunction of shearM. Jitianu*, Rutgers University, USA; C. Rohn, Malvern Instruments, Inc.,USA; R. A. Haber, Rutgers University, USA

The understanding of rheological properties of suspensions of ti-tania particles is important for most of industrial processes. Therheological behavior of suspensions of two kinds of TiO2 synthe-sized via sulfate process has been investigated. The goal was to un-derstand the role of synthesis parameters in the aggregation behav-ior of these powders. Investigation via scanning electron

microscopy SEM of the pristine powders revealed three differentaggregation levels. Secondary and higher order aggregate strengthwas investigated via oscillatory stress rheometry. Specifically, G’and G’’ were measured as a function of the applied oscillatorystress. Oscillatory rheometry indicated a strong variation as afunction of the sulfate level of the particles in the viscoelastic yieldstrengths. To assess different degrees of aggregation of titania pow-ders in suspensions, a novel freeze-drying technique along withSEM imaging has been developed to investigate the slurries beforeand after the yield point.

2:40 PMMolecular Engineering of Inorganic Nanoparticles andSuperstructured Nanomaterials (Invited)M. Z. Hu*, Oak Ridge National Laboratory, USA

Molecular-level chemical engineering of surfaces/interfaces innanoparticle-based and porous nanostructures is important to pre-cisely create novel functional inorganic nanomaterial architecturesand devices for diverse applications. This talk will focus on our re-search efforts toward nanostructure tailoring/control of functionalnano-materials and their energy (fuel cells), medical, and biotechnol-ogy applications. For example, our pioneering development of highlyoriented/ordered meso-structures and quantum dot superstructureswill be highlighted.

3:20 PMNanoparticle-based Bulk Material TemplatingK. Lu*, C. Hammond, Virginia Polytechnic Institute and State University, USA

Liquid processing has the most promise for nanostructured bulkmaterial forming. Our efforts have been focused on understandingand developing a water-based system to create stable nanoparticlesuspensions of high solids loading. With this, a new forming processfor nanostructured materials, freeze casting, has been studied withthe objective to bridge multiple length scales. This approach has thedesired ability to maintain dispersed state of high solids loading sus-pension with different aspect ratio species, such as nanoparticleswith a range of size distribution and nanoparticle-carbon nanotubecomposites. The process can make complex, near-net shape, andfine features with high green density. This talk will discuss the neces-sary conditions for producing high solids loading nanoparticle sus-pensions, followed by study of nanoparticle-based bulk materialtemplating.

3:40 PMSynthesis and characterization of mesoporous nanostructuredTiO2-Al2O3 photocatalytic systemM. García-Benjume, Universidad Michoacana de San Nicolás de Hidalgo,Mexico; I. I. Espitia-Cabrera, Universidad Michoacana de San Nicolás deHidalgo. , Mexico; M. Contreras-García*, Universidad Michoacana de SanNicolás de Hidalgo, Mexico

In the TiO2-Al2O3 photocathalytic system, anatase (tetragonal tita-nia phase) crystallize at low temperatures from amorphous materialsprepared by the symultaneous hydrolysis of titanium and aluminiumalkoxides. In this work, nanostructured mesoporous TiO2- Al2O3photocatalyst, with 10, 20 and 30 % Al2O3, have been obtained bysol-gel hydrothermal synthesis and molecular self-assembly usingtween 20 as a surfactant, then calcinning at 400C, at this temperature,only anatase phase was obtained, specific surface areas up to 295m2/gr were obtained, with mean pore diameters from 6.6 to 9.2 nm.All samples presenting type IV isotherms. The reactions and trans-formations were followed by thermogravimetric analysis. The mor-phology and nanostructure of the obtained TiO2-Al2O3 meso-porous photocatalyst were observed by SEM, TEM and HRTEM .Mean chrystallite sizes from 4 to 5nm were determined by TEManalysis.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 157

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania158

Nanotechnology: Nano-Materials forElectronic & Multifunctional Applications

Nanoscale Synthesis and AssemblyRoom: 409Session Chairs: Sharmila Mukhopadhyay, Wright State University;Raj Singh, University of Cincinnati

2:00 PMManufacturing at the Nano-Scale: Dreams to Reality, Lab toMarket (Invited)K. P. Cooper*, Naval Research Laboratory, USA

Nano-manufacturing science will bring to realization the benefits ofnanotechnology to individuals and society. New discoveries and sci-entific advances are rapidly transforming our understanding of mate-rials behavior at the nanometer scale and opening new possibilities innanotechnology. Nanotechnology’s roadmap involves the develop-ment of more complex concepts such as active nanostructures,nanostructured systems and molecular nanosystems1. A nano-manu-facturing research program must explore these new opportunities,including bio-inspired processes, and foster practical ideas for toolsand platforms for low cost, high-throughput production. In addition,nano-manufacturing research should leverage concepts such as simu-lation-based engineering and science and cyber-enabled manufactur-ing. In this paper an overview of nano-manufacturing concepts withexamples of recent research work will be presented. 1Mihail C. Roco,“Nanotechnology’s Future”, Scientific American, August 2006, p. 39.

2:40 PMSite-Specific Stamping of Graphene Patterns and Fabrication ofGraphene-Based Nanoelectronic DevicesD. Li*, N. Padture, W. Windl, Ohio State University, USA

A new idea is presented for the fabrication of graphene-based nano-electronic devices: site-specific stamping of graphene patterns. This isin response to the tremendous interest generated in graphene (2-Dcarbon crystals) recently, where graphene has been shown to possesssome highly unusual and exciting new properties, such as ballisticconduction, quantum Hall effect, magneto-transport, chemical sens-ing, and others. This new method has the potential to overcome someof the critical fundamental barriers associated with the current meth-ods used to create graphene-based electronic devices. Results fromthe experimental effort and the density-functional-theory basedatomistic modeling, which is guiding the experiments, are presentedand discussed.

3:00 PMMineral based fungus mediated synthesis of silver nano particlesand characterization studyP. K. Mishra*, N. Pradhan, Institute of Minerals and Materials Technology, India

Metal nano particle finds application in ptoelectronics, catalysis, re-prography, photoelectrical,drug therapy, cancer detection,synthesisof advancedceramic composites, energy storage devices etc.The pres-ent paper deals with preparation and characterization of silvernanoparticles of spheroidal,bipyramidal and triangular shape and sizevarying from 2-50nm by mineral based fungus mediated synthesiswith their comparison study.Silver nano particle in the sol and alsodry form have been characterized by UV-VISspectrophotometer,XRD and TEM. XRD patterns were obtained afterputting the nano sol on a glass substrate and then freeze drying it.Thescanning was doneata scan rate of 2theta= 2deg./minusing CuK(alpha)radiation.The nano particle film were formed on carboncoated copper grids and observed under TEM at a voltage of 200KV.The shape and size of the nano particles were also studied bySmall angle x-ray scattering techniques.The results will be presentedin the full paper.

3:20 PMInteraction of Metal Nanoparticle Compact and ElectromagneticWave at GHz frequenciesK. Matsumura*, Y. Kagawa, The University of Tokyo, Japan

At GHz frequencies, low dielectric polymers and ceramics are used astransmitting materials, and electromagnetic shielding is achieved by met-als since electromagnetic wave doesn’t transmit a metal material. Electro-magnetic shielding behavior is an essential nature of metals originatedfrom free electrons in the metals. However, we found unique interactionbetween metal nanoparticle compacts and electromagnetic wave in GHzfrequency range. The purpose of this study is to show transmission be-havior of metal nanoparticle compact, and interaction mechanisms be-tween the nanoparticle compacts and electromagnetic wave is discussed.

3:40 PMMicrowave Transmittance of Nano-Aluminum Particle-DispersedEpoxy Matrix CompositesS. Utsuno*, K. Matsumura, Y. Kagawa, the University of Tokyo, Japan

Aluminum nanoparticles have unique interaction between microwaveand their compacts: the compact behaves as ultra-low dielectric behav-ior (K.Matumura and Y.Kagawa: J. Appl. Phys., 2008). The present studyhas been focused on possibility of aluminum nanoparticle-dipersedepoxy matrix composites as microwave transmittable material. Alu-minum nanoparticle (average diameter: 45nm)-dispersed epoxy matrixcomposites with volume fraction up to 0.2 were fabricated and dielectricbehavior of the composites at a frequency range from 18 to 30GHz wasmeasured using free space method. The composites showed interestingdielectric constants compared with micron-meter size aluminum parti-cle-dispersed ones: both low real and imaginary values. From measuredeffective dielectric constants of the composites, thickness dependence ofelectromagnetic transmittance was calculated and the potential of elec-tromagnetic wave transmittable composite materials was discussed.

4:00 PMDevelopment of Graphene-Based Nanostructured Polymer Blendsfor EMI ShieldingR. Cieslinski*, H. Fowler, D. Strand, V. Wani, M. Paquette, The Dow ChemicalCompany, USA

Recently, there is a renewed interest in producing single graphene sheetsin bulk quantities through the thermal expansion and reduction ofgraphite oxide. In this paper, we report on the development of an extrin-sically conductive polymer (ECP) using graphene nanoplatelets.Graphene, with its unique combination of electrical conductivity andhigh aspect ratio, is an extremely efficient filler for generating ECP com-posites. Molded enclosures from these composites are capable of shield-ing electromagnetic (EM) energy for electronic applications. Volume re-sistivities less than 100 Ω cm are achievable with loading around 5 wt%that is capable of reducing EM energy from a source device by 45 to 60 db.

Processing & Product Manufacturing:International Symposium on Ceramic MatrixComposites

Composite Processing and Characterization IIRoom: 413Session Chairs: Ivar Reimanis, Colorado School of Mines; EdgarLara-Curzio, Oak Ridge National Laboratory

2:00 PMFabrication and Modeling of Nanoengineered Al2O3/WC-CoCompositesD. J. Cunningham*, I. Smid, Pennsylvania State University, USA; J. Keane,Allomet Corporation, USA

Tough Coated Hard Particles (TCHP) are a hard metal compositematerial comprised of extremely hard Al2O3 core particles encapsu-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 158

Tues

day

PM

www.matscitech.org 159

lated in a tough WC-CO shell. Fabrication methods were studied aswell as the effect they posed on the mechanical properties of the ma-terial. Finite element modeling was used to model the interactions ofthese TCHP materials in wire drawing dies. These models showedthat during the drawing process the wire at the exit of the die reachedlocal stresses of almost three times its yielding strength. These stressconcentrations were found to be small and only caused severe plasticdeformation in the steel wire at regions directly near the die exit re-gion. Using non-linear material properties for steel, permanent strainof the wire due to plastic deformations were found as well as thestress states imposed by them. Future advances these finite elementsimulations could include predictions of wear lifetime as well as in-fluence of temperature.

2:20 PMMechanical Properties of Zirconium Carbide-Tungsten CermetsPrepared by In Situ Reaction SinteringM. M. Giles*, S. C. Zhang, W. G. Fahrenholtz, G. E. Hilmas, MissouriUniversity of Science and Technology, USA

Zirconium carbide-tungsten cermets were prepared by in-situ reac-tion sintering a mixture of zirconia and tungsten carbide. Tungsten isa refractory metal with a melting point of 3422°C; however, its me-chanical strength decreases significantly with increasing temperature.One approach to improve the elevated temperature strength is to addceramics to the matrix. Zirconia and tungsten carbide were com-pacted and then reacted and sintered in a single step by heating to2100°C. The resulting zirconium carbide-tungsten cermet had a rela-tive density greater than 96%. Cermets with two different grain sizeswere produced by altering the atmosphere during reaction and thefinal sintering temperatures. The composite strength was measured atroom and elevated temperatures. The effects of the composition andgrain size on the mechanical properties were evaluated.

2:40 PMFracture Toughness and Microstructural Characterization of ββ-EucryptiteS. Ramalingam*, T. W. Jochum, R. E. Ivar, Colorado School of Mines, USA

The fracture toughness of β-eucryptite (LiAlSiO4), a ceramic exhibit-ing unique thermoelastic properties, was evaluated. The sensitivity ofcrack growth in β-eucryptite to moisture was examined by conduct-ing experiments in dry and humid atmospheres. Specimens weremade by synthesizing β-eucryptite powder with two different routes,and then free-sintering or hot pressing it. Microstructures of β-eu-cryptite processed by different methods were examined with opticalmicroscope and SEM, including electron backscattering diffraction,and these results are correlated with the fracture behavior.

3:00 PMEffect of flow rate, nitrogen precursor and diluent on Si2N2Odeposition by HYSYCVDA. L. Leal-Cruz, M. I. Pech-Canul*, Cinvestav Saltillo, Mexico; E. Lara-Curzio,Oak Ridge National Laboratory, USA

The effects of flow rate, nitrogen precursor and diluent on the synthe-sis of Si2N2O by the hybrid precursor chemical vapor depositionmethod (HYSYCVD) were investigated. Based on an L9 Taguchi ex-perimental design, the processing parameters were studied at threelevels: flow rate (10, 15 and 20 cc/min), nitrogen precursor (UHP-N2,50% N2-balance ammonia, and 5 % N2-balance ammonia), anddiluent (Ar, He, and with no use of diluent). Results from the charac-terization by XRD and SEM show that in the temperature range 880-1330 oC and processing times between 0-70 min, Si2N2O is formedas spheres, rough and fine fibers. Anova shows that flow rate of nitro-gen precursor has the highest relative contribution (46 %) to the for-mation of Si2N2O, followed by the type of nitrogen precursor (44 %)and, the type of diluent (8 %). Deposition of Si2N2O is maximizedby using 10 cc/min of UHP-N2 and without diluent.

3:20 PMMechanical properties of αα/ββ-SiAlONs fabricated by nitriding andpost-sintering of Si mixtureY. Park*, E. Noh, J. Ko, H. Kim, Korea Institute of Materials Science, South Korea

Hardness and fracture toughness of Y-stabilized α/β-SiAlONs wasmeasured for the specimens fabricated by nitriding and post-sin-tering of Si mixture. Eight different (m,n) values in YxSi12-(m+n)Alm+nOnN16-n were selected to cover wide range of α-SiAlON fraction in the composites. Hardness of >20 GPa andfracture toughness of >5.5 MPam1/2 was achieved. With increasein sintering time at 1900oC, increase in hardness and decrease infracture toughness was measured. The former is attributed to theincrease in α-SiAlON fraction, while the latter needs carefulanalysis including the effect of grain growth and phase ratio.Methodology to enhance the fracture toughness was suggested inthe conclusions.

3:40 PMEffect of Variations in Process Shear on the Mixedness of anAlumina – Titania SystemC. August*, R. Haber, M. Jitianu, Rutgers University, USA

Alumina-titania compounds are used in industries ranging fromcatalyst production to wear resistance coatings. Their creation re-quires different mixing techniques and forming processes. The goalof this work is to understand the effect of different mixing tech-niques on the component distribution (mixedness) of the alu-mina-titania batch. Techniques employed include wet mixing, drymixing with compounding, and dry mixing with multiple extru-sions. An analysis of the effect of processing conditions on themixedness of these alumina-titania extrudates has been performedusing scanning electron microscopy followed by energy dispersivex-ray analysis. Rheological properties of the extruded pastes havealso been measured. Overall mixedness of the alumina-titaniabatch has been found to vary with the process shear applied bymixing.

4:00 PMThermal and Electric Conductivity of Near-zero ThermalExpansion ZrW2O8/ZrO2 CompositesX. Yang*, Shanghai Institute of Optics and Fine Mechanics, Chinese Academyof Sciences, China; X. Cheng, Jiangsu University, China; H. Li, J. Xu, ShanghaiInstitute of Optics and Fine Mechanics, Chinese Academy of Sciences, China

In this work, the microstructure, thermal and electric conductivityproperties of near-zero thermal expansion ZrW2O8/ZrO2 (S1) andAl2O3 added ZrW2O8/ZrO2 (S2) composites were studied. The mi-crostructure of the composites was observed by scanning electronmicroscope (SEM), the thermal diffusivity was tested by laser-flashthermal diffusivity methods and the electrical conductivity wasmeasured with an impedance analyzer. The average thermal conduc-tivity of S1 and S2 is 1.386 and 1.793 Wm-1K-1 respectively in thetemperature range of 298~473K and the thermal conductivity de-creases slightly as the temperature increases. The electric conductivityof the two composites increases with the increasing of the measure-ment temperature. The Al2O3 added ZrW2O8/ZrO2 composite hashigher thermal and electric conductivity than ZrW2O8/ZrO2 com-posite. The most important factor which causes the difference ther-mal and electric conductivity between the two composites is theporosity.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 159

Tuesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania160

Processing & Product Manufacturing: Joiningof Advanced and Specialty Materials X

Micro and Nano-JoiningRoom: 410Session Chairs: Mathieu Brochu, McGill University; Norman Zhou,University of Waterloo

2:00 PMFreeform Fabrication of WC-Co/SUS304 Composite Materials byUsing Three Dimensional Micro Welding (Invited)Y. Yamamoto*, S. Kirihara, Osaka University, Japan

A novel freeform fabrication process for metal or alloy componentsnamed three dimensional micro welding (3DMW) has been pro-posed. In this system, a tungsten inert gas (TIG) welding machine iscontrolled by using CAD/CAM processes. Various types of metal oralloy wires are fed automatically under a micro-arc torch to form tinymetallic beads. These micrometer order beads are joined continu-ously to build three dimensional structures. Near-net-shape compo-nents of metal or alloy compounds with high melting points can befabricated automatically with minimized energy and resources. Inthis study, tungsten carbide-cobalt (WC-Co) and stainless steel(SUS304) micro beads of 200 μm in diameter were stacked up alter-nately to fabricate cutting tools by using the 3DMW. The microstruc-ture and hardness were observed by scanning electron microscope(SEM) and Vickers hardness tester. The maximum hardness of microbead was approximately 1300 Hv and no crack or pore existed in theformed objects

2:40 PMFreeform Micro Fabrication of Metal Structures to ControlElectromagnetic Wave by Using Stereolithography (Invited)S. Kirihara*, D. Sano, Osaka University, Japan

We have newly developed micro-stereolithography system to realizefreeform fabrication of micrometer order 3D metal structures. In thisprocess, the photo-sensitive resin paste mixed with nanometer sizedmetal particles is spread on a glass substrate with 10 μm in layerthickness by using a mechanical knife edge, and a two-dimensionalimage of UV ray is exposed using DMD (Digital Micro-mirror De-vice) with 2 μm in part accuracy. Through the layer by layer stackingprocess, micrometer order three-dimensional objects are formed.Dense metal structures can be obtained by dewaxing and successivesintering of the formed objects. In our recent investigation, microphotonic crystals with lattice structures of pure copper were fabri-cated in order to control electromagnetic wave propagation in a tera-hertz (THz) frequency range. The micro photonic crystals with a dia-mond structure perfectly reflected the THz wave by Bragg diffraction.

3:20 PMOptimization of Control Variable for Resistance Spot WeldingJ. Bai*, L. J. Brown, The University of Western Ontario, Canada

Resistance spot welding is widely used as an efficient joining tech-nology for assembling metal components in the automotive, bio-medical and electronics industry. The demand for improved weld-ing consistency has led to switching from voltage control tocurrent control. In addition, commercially available micro-spotwelder also may provide power control mode. In this context,power can be interpreted as square of the geometric mean of volt-age and current. In fact, any weighted mean of voltage and currentcan be used as a viable control variable. Based on this insight, it isrecognized that there should be one specific weighted mean ofvoltage and current that can lead to the least variance in heat pro-duced in weld nugget for resistance spot welding process. Forwelding 0.152mm gauge stainless steel, we found a 40% weightedon the voltage produced the most consistent weld nugget diame-ter. And with this control parameter, a 60% improvement in vari-

ance in weld nugget size versus constant current control wasachieved.

3:40 PMNon-PR Bumping and Wafer Stacking by Microsoldering forElectronicsS. Hong, Amkor, South Korea; J. Cheon, H. Lee, J. Jung*, University of Seoul,South Korea; M. Mayer, Y. Zhou, University of Waterloo, Canada

Feasibility of a new process of a direct solder bumping on Si waferwithout Photo Resist (PR) and wafer stacking was studied for cost re-duction and high productivity. A Si wafer was etched by SF6 andC4F8 alternately to make via holes. The vias are 40μm in diameterand 80μm in depth. On the via wall, SiO2, Ti, Au layers are formedand pulsed DC electroplating was used to fill the via with Cu. Thenthe Si was back grinded to a thickness of 80μm until the Cu exposes.Plating current flowed through the via to the bumping surface, andSn bump was plated on the Cu without PR mould. To optimize theprocess, the current density and time were varied to 0.06 A/cm2 and40min respectively. As current and time increased, the bump heightincreased. Optimized Sn bumps with 20μm height were formed suc-cessfully by 0.05A/cm2-30min. Three Si dice with thickness of 80 μmwere stacked by Sn soldering in air at 260°C. Thus, a non-PR Sn sol-der bumping by electroplating and wafer stacking with vias wasachieved successfully.

4:00 PMElectroSpark Welding of Thermally Sensitive MaterialsS. Cadney, G. Goodall, McGill University, Canada; A. Moran, United StatesNaval Academy, USA; G. E. Kim, Perpetual Technologies, Canada; M.Brochu*, McGill University, Canada

ElectroSpark Welding (ESW) is an arc welding process that uses ashort duration, high energy electrical pulse to deposit electrode mate-rial onto a conductive substrate. Due to short pulse durations (4-60μs) and high pulse frequencies (0.1-4 kilohertz), the ESD process iscapable of dissipating heat in ~99% of the duty cycle while heatingfor only ~1% of that time. This results in cooling rates that may ap-proach 105 to 106 °C/sec. The rapid cooling rates in conjunction withthe very small weld volume can be sufficient to create nanostructuredor amorphous deposits depending on the alloy composition. Thispresentation will focus on the advances obtained on ESW of twoamorphous materials, Vitreloy 1® and an AlCoCe alloy onto amor-phous and nanostructured materials without crystallizing or induc-ing grain growth of neither the deposit nor the substrate. This tech-nique opens the door to repair of damaged amorphous ornanocrystalline components/coatings.

4:20 PMNanoscale Joining of Dissimilar Materials Using a Ti-dopedBrazing AlloyW. Wu*, Y. Zhou, M. Yavuz, University of Waterloo, Canada; J. Wei, K. Wang,Tsinghua University, China

This research aims at volume productive, less expensive and morecompatible joining techniques for integration and packaging of nanobuilding blocks such as carbon-nano-tubes (CNTs) for nanoelec-tronics devices requiring low contact resistance. Here we shownanoscale vacuum brazing of CNTs with a eutectic alloy (AgxCuy)doped with Ti. Bonding is confirmed to involve formation of cova-lent bonds between Ti and C atoms. The vacuum reduces diffusion ofO atoms into the interconnection area, giving an opportunity to theTi and C atoms to interdiffuse and react at the joining interfaces. Co-valent bonding is vital for durable joints at nanoscale among dissim-ilar materials, particularly ceramics-metals, and is thought to beformed primarily by the unfilled d-shell electrons shared betweentransition metal atoms such as Ti used as dopant in the brazing alloyand the C atoms.

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 160

Wed

nes

day

AM

www.matscitech.org 161

Processing & Product Manufacturing:Processing, Properties and Performance ofComposite Materials

Metal Matrix Composites - NanocompositesRoom: 412Session Chairs: Nikhil Gupta, Polytechnic University; RamanaReddy, University of Alabama

2:00 PMSolidification Processing of Metal Matrix Nanocomposites(Invited)P. K. Rohatgi*, N. Gupta, B. F. Schultz, Polytechnic University, USA

Nanocomposites are playing an important role in enhancing the per-formance levels of components in a variety of applications. The pres-ent state of the art in the processing and properties of bulk-engi-neered metal-matrix nanocomposites is discussed. A combination ofmaterials, composition and processing can provide nanocompositeswith improved hardness and strength, improved wear resistance andreduced friction coefficients. Although relatively few studies have ex-plored the solidification synthesis of nanocomposites compared tothe powder processing and mechanical mixing approaches, the tech-nological viability of solidification processing has been identified.This review focuses on solidification as a processing method, andidentifies critical gaps in knowledge on solidification synthesis ofmetal matrix nanocomposites. Fundamental challenges in the solidi-fication synthesis of nanocomposites are highlighted and key researchopportunities are identified.

2:40 PMMetal Matrix Micro and Nano Composites (Invited)M. K. Surappa*, Indian Institute of Science, India

Metal Matrix Composites (MMCs) are materials in which metallicbase material (Al / Mg / Cu) is reinforced with a ceramic phase (in theform of continuous / discontinuous / nano size) in order to achieveor combination of attributes not attainable by either of constituentsalone. Research on synthesis of Metal Matrix Composites was nucle-ated at the Indian Institute of Science nearly three decades ago, with alimited objective of substituting expensive copper based materialsthrough the development of aluminum based composites. Over theyears variety of Aluminum / Magnesium based metal matrix compos-ites containing C, SiC, Al2O3, B4C and fly ash as reinforcements havebeen synthesized using stir-casting route (known as Indian Innova-tion). Presently, Metal Matrix Composites (MMCs) have emerged asan important class of materials with the potential to replace a numberof conventional materials being used in automotive, aerospace, de-fence and leisure industries where the demand for light weight andhigher strength components is increasing.

3:20 PMMechanical Behavior of Ceramic Reinforced AluminumNanocompositesL. An*, University of Central Florida, USA

Aluminum matrix nanocomposites, which contain various amountsof different sized Al2O3 particles, are prepared by mechanical-alloy-ing followed by hot-pressing. The microstructures of the compositesare characterized using optical microscopy, scanning electron mi-croscopy (SEM) and transmission electron microscopy (TEM). Me-chanical behavior of the composites is characterized using wear-test-ing and indentation techniques. The results show that thenanocomposites containing the high volume fraction of Al2O3nanoparticles exhibit unique mechanical behavior. For example, theirwear resistance is even better than stainless steel. The observed me-chanical properties will be discussed in terms of the structures.

3:40 PMStructure and Mechanical Properties of Stir Cast Aluminum alloy-Al2O3 Nanoparticle CompositesB. F. Schultz*, P. K. Rohatgi, J. Ferguson, University of Wisconsin-Milwaukee,USA; S. Alaraj, Birzeit University, Israel

Metal matrix nanocomposites (MMNC) reinforced with dispersednanosized ceramics have the potential of ultra high strength and im-proved tribological properties. To date, most of the developmentsand research in the synthesis of metal matrix nanocomposites havefocused on powder metallurgy techniques and deformation process-ing. The authors have developed cast lightweight aluminumMMNC’s through vortex mixing and the use of magnesium as a wet-ting agent. This study discusses the influence of mixing time,Al2O3np content and Mg content on the structure and mechanicalproperties of an A206 alloy – Al2O3np (47 nm) composite. The castcomposites were examined by optical and transmission electron mi-croscopy, and the hardness of the as cast and heat treated specimenswere determined. Optimal processing parameters determined in thisstudy are discussed.

4:00 PMProcessing, Microstructural Characterization and UltrahighDamping of a Ti2AlC/Nanocrystalline Mg-Matrix CompositeS. Amini*, Drexel University, USA; C. Ni, University of Delaware, USA; M. W.Barsoum, Drexel University, USA

Herein we report, on the processing and microstructural characteri-zation of highly oriented and random Ti2AlC/nanocrystalline Mg-matrix composites fabricated by pressureless melt infiltration. XRDand TEM both confirmed that the Mg grain size was ~35±15 nm.These grains were also exceptionally resistant to grain growth; an-nealing the composite 100°C higher than the melting point of Mg, for1 h did not significantly alter their size. Small amounts of Ti, Al and O– postulated to be the nucleating agents – were found in the Mg-ma-trix. These composites are machinable, stiff (80 GPa) and light (2.7g/cm3) and exhibit exceptional damping capabilities – that increaseas the square of the applied stress. The energy dissipated per unit vol-ume at 500 MPa is believed to be the highest ever reported for a crys-talline solid. The technological implications of having such solids willbe discussed.

Wednesday, October 8, 2008

Special Topics: The National MaterialsAdvisory Board Dissemination Series

National Materials Advisory Board SessionRoom: 401Session Chair: Gary Fischman, The National Academies

8:00 AMNMAB Overview (Invited)G. Fischman*, National Academies, USA

Abstract Not Available

8:40 AMManaging Materials for a 21st Century Military (Invited)R. Latiff*, Science Applications International Corp. (SAIC), USA

Abstract Not Available

9:40 AMIntegrated Computational Materials Engineering (Invited)T. Pollock*, University of Michigan, USA

Abstract Not Available

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 161

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania162

Special Topics: Perspectives from EmergingMaterials Professionals: Early Strategies forCareer Development

Key Strategies for Career Development IRoom: 403Session Chairs: Nathan Ashmore, The Boeing Company; EmilyKinser, IBM

8:40 AMCareer Development to be a Multi-National and Multi-Disciplinary EngineerB. Li*, Metal Pass LLC, USA

Experiences are shared on how to perform self-training to becomeone of the most dynamical engineers, for integrating German engi-neering, US IT and Chinese market. With over 30 years of training,the author has gained three countries’ working experiences, four lan-guages and skills on material engineering, mechanical engineering,software engineering and industry automation. After receiving Ph.D.,working on rolling process modeling and publishing a book, the au-thor spent recent 10 years to be a mill-automation software engineerand to do mill application development. To be a highly qualified soft-ware engineer, the author completed 30 computer classes. Criticalfactors for success are to plan ahead and to brew interest in the thingsto be done. The paper also outlines author’s results on the millprocess models, web-based applications, general design on the next-generation Level 2 systems and a book in writing on steel mill processmodeling and computer application, etc.

9:00 AMPerspective from a Government LaboratoryM. Welk*, Sandia National Laboratories, USA

Abstract Not Available

9:20 AMPerspective from AcademiaM. S. Kennedy*, Clemson University, USA

Abstract Not Available

10:00 AMEngineering Narrative: Telling a Story to Any AudienceW. M. Kane*, Exponent, USA

The days of an engineer or scientist being locked away in a lab are allbut over. Modern technical collaboration requires a greater degree ofcommunication with a wider range of audiences. Engineers must beable to present our work in a concise manner, often to a lay listenerwith no technical background. Effort must be made, therefore, to thenarrative quality of our discussion. Complex topics must present in away that is engaging and understandable. In this talk we examine thisprocess in the context of an engineering failure analysis of a medicaldevice. The steps and processes used to craft a compelling story of theresults will be presented, including a review of the typical techniquesutilized in many failure analyses. Starting with an exemplar and end-ing with the subject device, we use documentation, standards, testingand analysis to create an effective narrative. The physical evidencecreates a sequence of events that resulted in the failure, and most im-portantly identifies a root cause of that failure.

10:20 AMDr. Liu’s TKC Theory (Invited)Z. Liu*, The Pennsylvania State University, USA

Abstract Not Available

11:00 AMHow to Succeed in a Government Lab by Really Trying (Invited)I. E. Anderson*, Ames Laboratory, USA

Abstract Not Available

Special Topics: Industry Track 2008

Industry Track 2008, Wednesday AMRoom: Hall A

10:30 AMEliminating Frame-based Creep with a Novel NanoindentationMethod (Invited)J. Powell*, CSM Instruments Inc., USA

Abstract Not Available

11:00 AMOak Ridge’s HTML: A National Resource for CollaborativeMaterials Research (Invited)C. Goudy*, Oak Ridge National Laboratory, USA

Located at the Oak Ridge National Laboratory, the HTML combinesskilled staff and specialized instruments to solve materials problemsthat limit the efficiency and reliability of energy systems. HTML re-search is focused on materials for: lightweighting, thermoelectrics,energy storage, catalysts, and propulsion. Overviews of the HTMLUser Program’s six centers and highlights of successful user projects.

Electronic & Magnetic Materials: Fabrication,Microstructures and Interfacial Properties ofMultifunctional Oxide Thin Films

Processing and Applications of Oxide FilmsRoom: 315Session Chairs: Ram Katiyar, University of Puerto Rico; Long-qingChen, Pennsylvania State University

8:00 AMThe Stability of Thin Metal Films in Contact with Oxides (Invited)W. D. Kaplan*, Technion - Israel Institute of Technology, Israel

Due to the relative interface/surface energies at metal-oxide inter-faces, thin metal films on oxide substrates are intrinsically unstable.As a result, thermal annealing will result in the break-up (or dewet-ting) of thin films, resulting in small droplets if the process is con-ducted above the melting point of the metal, or in small solid parti-cles if the process is conducted below the melting point of the metal.The process can be kinetically slowed by engineering the relative in-terface/surface interfaces via equilibrium segregation. Grain bound-ary grooving of the thin film was thought to be the mechanism fordewetting, but recent experiments have shown that dewetting initi-ates via the formation of voids at the metal-oxide interface, via va-cancy diffusion. These issues, and the concept of stable equilibriumfilms, will be explored in this presentation.

8:40 AMManipulating Structural, Dielectric and Insulating Properties ofBa0.60Sr0.40TiO3 (BST) Thin Films by Ultra-violet IrradiationA. A. Podpirka*, Harvard University, USA; M. W. Cole, U.S. Army ResearchLaboratory, USA; S. Ramanathan, Harvard University, USA

In this presentation, the effect of ultra-violet (UV)-assisted anneal-ing on the structural, dielectric, and insulating properties of bariumstrontium titanate (BST) thin films will be discussed. The propertiesof BST films, prepared by RF sputter deposition, annealed via con-ventional thermal annealing and UV-assisted thermal annealingprocess protocols, were compared and evaluated. The x-ray diffrac-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 162

Wed

nes

day

AM

www.matscitech.org 163

tion results showed contracted lattice constants and enhanced crys-tallinity for the BST films annealed via UV-assist treatment. The di-electric loss and leakage current density of the films was signifi-cantly reduced by employing UV-assisted annealing withoutdegradation of film tunability. Mitigation of oxygen vacancies, asso-ciated with the UV-assisted annealing, is likely responsible for theimprovement of the dielectric and electrical properties of the BSTthin films.

9:00 AMSpectral Imaging of the ΣΣ=5 Grain Boundary in Perovskite SrTiO3Using Ab Initio Data and Function Field Visualization (Invited)P. Rulis*, W. Ching, University of Missouri - Kansas City, USA

Electron energy-loss spectroscopy (EELS), in conjunction with highresolution transmission electron microscopy (HRTEM) at sub-angstrom atomic resolution, has been an effective characterizationtool for imaging microstructural materials. However, many technicalchallenges remain. We show that by using accurate data obtainedfrom ab initio calculations of atom-specific absorption edges and byincorporating function field visualization, it is possible to relate theeffects of interatomic interactions with specific spectral variations. Asymmetric 53° <001> tilt Σ = 5 grain boundary in SrTiO3 whichcontains buckled Sr columns and alternating Ti-O columns in the<001> projection is used to demonstrate this method. Such spectralfeature extraction and identification may be a useful new characteri-zation tool.

10:00 AMResistance Switching Memory: Material Design and ConductionMechanisms (Invited)I. Chen*, Y. Wang, S. Kim, University of Pennsylvania, USA

Oxide resistance switching memory (RRAM) has potential for appli-cations to replace flash memory. Where a phase transformation isnot involved, interface mechanisms and ion conduction mecha-nisms have been reported to be responsible for switching and form-ing—a post-fabrication voltage-stressing procedure that causes di-electric breakdown, thus enabling resistance switching thereafter.Here we report a series of epitaxial oxide thin film heterostructuresas a new family of RRAM that requires no forming and involves onlyelectronic conduction. The role of interface mechanisms was exam-ined using different electrodes and buffer layers and found absent.Ionic conduction was ruled out by use of light to induce switchingthat involves no electric field. The electronic conduction mecha-nisms were identified by comparing the I-V data with models at var-ious temperatures. We conclude that robust, low-impedance, elec-tron-dominant RRAM can be realized in epitaxial oxide thin filmheterostructures.

10:40 AMElectrode material effects on the dielectric properties of nano-scale sputtered BaTiO3 thin filmsJ. Reck*, M. O’Keefe, F. Dogan, University of Missouri - Rolla, USA

Magnetron sputtering of sequential nano-scale, conformal, alternat-ing layers of dielectric and metallic films with chemical and morpho-logical uniformity has the potential to greatly increase capacitancedensity. In this study sputtering of BaTiO3 was used to deposit filmswith thickness ranging from 25 nm to 200 nm between 30 nm thicklayers of sputtered Ni or Pt electrodes. The BaTiO3 was sputtered at10% and 50% oxygen in the plasma, RF power densities of 3.3 and 4.4W/cm2, and deposition temperatures of 25°C, 160°C, and 300°C.Device yields were an average of 99.8% with Ni electrodes and 96.2%with Pt. All capacitors fit a standard dead-layer model with bulk per-mittivity values from 324 to 758 for Ni and 1233 to 1656 for Pt, withinterface permittivities between 15 and 45 for Ni and 32 to 180 for Ptdepending on the processing conditions of the BaTiO3 layer.

11:00 AMSurface Chrominated Thick Films of Ba(0.8)Sr(0.2)TiO3 for H2SGas Sensing (Invited)G. H. Jain*, Arts, Comm.& Sci. College, Nandgaon, India; L. A. Patil, PratapCollege, India

In this paper, H2S gas sensing behavior of Barium strontium titanate(BST) thick films have been reported for the first time. Thick films ofBST were prepared by screen-printing techniques. The sensing per-formance of the films was tested for various gases. To improve the sen-sitivity and selectivity of the film towards a particular gas, BST thickfilms were surface modified by dipping them in an aqueous solution ofchromium trioxide (CrO3) for different intervals of time. These surfacemodified (chrominated) BST films showed larger sensitivity to H2S gas(300 ppm) than pure BST film. A systematic study, of sensing perform-ance of the sensor, indicates the key role played by the chromiumspecies on the surface .The sensitivity, selectivity, repeatability, stability,response and recovery time of the sensor were measured and presented.

Electronic & Magnetic Materials:Ferroelectrics and Multiferroics

Physical Properties and Nanoscale Phenomena inFerroelectric, Ferromagnetic, and MagnetoelectricThin Films and NanostructuresRoom: 318Session Chairs: Geoff Brennecka, Sandia National Laboratories; PaulClem, Sandia National Laboratories

8:00 AMBroadband Characterization of Ferroelectric and MultiferroicThin Films to 40 GHz (Invited)J. C. Booth*, N. D. Orloff, National Institute of Standards and Technology,USA; M. Murakami, I. Takeuchi, University of Maryland, USA

The electromagnetic response of ferroelectric and multiferroic thinfilms at microwave frequencies is important for a fundamental under-standing of lattice dynamics in these materials, as well for potentialapplications in electronics and communications systems. Broadband,swept-frequency measurements of the film permittivity, for example,can directly reveal high-frequency relaxation effects in the frequencydomain, which can be quantified and studied as a function of temper-ature, compostion, or bias field. We analyze and compare the broad-band dielectric response of a number of ferroelectric and multiferroicthin-film materials, including strontium titanate (SrTiO3), lead ti-tanate (PbTiO3), and PbTiO3-CoFe2O4 multilayers. Our measure-ments show how the high-frequency responses of thin-film materialschange as a function of material composition and temperature.

8:40 AMA modified Kittel’s scaling law for ferroic thin filmsL. Chen*, Nanyang Technological Univ, Singapore

The periodicity of 180 degree stripe-domains has been calculated analyt-ically by assuming a linear change of magnetization/polarization in thedomain wall. A modified Kittel’s law between the square of the domainwidth D and the film thickness t has been derived for both ferroelectricand ferromagnetic thin films. This general law is consistent with avail-able experimental data and offers a reliable method to discuss the prop-erties of ultrathin films, including multiferroic thin films such as BiFeO3.

9:00 AMDirect Observation of Domain Switching Dynamics inMultiferroicsJ. Bosse, N. Polomoff, R. Nath, University of Connecticut, USA; R. Ramesh,UC Berkeley, USA; B. D. Huey*, University of Connecticut, USA

Ferroelectric domain switching dynamics in multiferroic epitaxialthin films (BFO) are uniquely mapped with High Speed Scanning

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 163

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania164

Property Mapping. This AFM-based method is used to examine filmswith several distinct microstructures, including single and multipledomain orientation combinations, revealing unique nucleation andgrowth mechanisms and energetics. Results are compared as a func-tion of both pulsing time as well as pulsing potential beyond the co-ercive field. Correlations between domain nucleation sites (and/orpinning sites), nucleation and growth statistics, and film microstruc-ture are also directly mapped.

9:20 AMFerroic Phase Transitions and Finite Size Effects of Nano-Crystalline BiFeO3S. Selbach, M. Einarsrud, T. Tybell, T. Grande*, NTNU, Norway

BiFeO3 is the hitherto only known material exhibiting multiferroismat ambient temperature, but despite intense research the thermody-namic order, crystallographic nature of the ferroelectric phase tran-sition has not been established. Here, we report on the first orderphase transition from the ferroelectric R3c space group to the cen-trosymmetric R-3c space group. The transition is accompanied byan abrupt disappearance of the coupled polar atomic displacements.The antiferromagnetic transition is second order with continous lat-tice parameters but anomalous isotropic expansion. Electrical con-ductivity anomalies are demonstrated for both ferroic transitions.Moreover, BiFeO3 nanoparticles display strong size-dependent prop-erties. The Néel temperature was shown to correlate with the vol-ume of the crystallites and the polar displacements of cations. Thepresent findings of the nature of the two phase transitions providesbetter understanding of the ferroic properties of multiferroicBiFeO3.

10:00 AMOrigin of ferroelectric aging and the associated novel effect(Invited)X. Ren*, National Institute for Materials Science, Japan

Ferroelectric aging effect, a time-dependent changing of ferroelectric,dielectric and piezoelectric properties, is a long-standing issue ofboth fundamental interest and practical importance. Here I shall in-troduce a general microscopic theory to explain the origin of ferro-electric aging and explore the consequences of such a new under-standing. The theory is based on a general symmetry-conformingproperty of point defects. It provides a unified explanation for a widerange of seemingly different aging phenomena, like double hysteresisloop, the change in dielectric permittivity and in piezoelectric coeffi-cient. It also unifies the explanation for aging effect for both ferro-electrics and ferroelastics/martensites. Understanding of the mecha-nism of ferroelectric aging leads to guidelines for effective control ofthe aging effect. Finally it is shown that aging effect can be used forachieving a huge nonlinear electrostrain effect, which can be 40 timeslarger than the converse piezoelectric effect of PZT.

10:40 AMDielectric Properties of Ba(Zr,Ti)O3 Thin Films for TunableMicrowave ApplicationsJ. Liu*, G. Collins, J. Weaver, C. Chen, University of Texas at San Antonio,USA; J. Jiang, E. I. Meletis, University of Texas at Arlington, , USA; A. Bhalla,University of Texas at San Antonio, USA

Ba(Zr,Ti)O3 [BZT]thin films were prepared on (001)MgO substratesby using pulsed laser deposition. Microstructure characterizationswith x-ray diffraction and transmission electron microscopy indi-cated that the as-grown films have excellent single crystalline quality.The dielectric property measurements reveal that the as-grown filmshave a substantial dielectric constant value of 250 and a dielectrictunability of 54%. These results suggest that the highly epitaxial BZTthin film can be an excellent candidate for developing room-temper-ature, tunable microwave elements.

11:00 AMStrain effects and thickness dependence of ferroelectric propertiesin epitaxial BiFeO3 thin filmsL. Chen*, Nanyang Technological Univ, Singapore

A “misfit strain-temperature” phase diagram for BiFeO3 thin filmwas constructed based on the Landau-Devonshire theory with themechanical substrate effect. It is found that the polarization instabili-ties result in the formation of the monoclinic states in BiFeO3 thinfilms. The film thickness dependence of epitaxial strains has been in-troduced to calculate the film thickness dependence of the polariza-tion and the dielectric constants. The theoretical results are in agree-ment with the experimental data for the thickness dependence offerroelectric properties of the BiFeO3 epitaxial thin films on SrTiO3and Si substrates.

11:20 AMLeakage current reduction and improved ferroelectric properties ofchemical solution deposited Bi (Fe, M) O3 (M= Ti and Cr) thin filmsN. Murari*, R. Thomas, R. Katiyar, University of Puerto Rico, USA

BiFeO3 is an environmentally benign multiferroic material at roomtemperature and would be of immense technological importance forfuture electronic applications but the device applications of BiFeO3are severely hindered by its low electrical resistivity. It is believed thatthe B-site substitution with proper cation may lessen the oxygen va-cancies, thereby reducing the leakage current. So we fabricated Bi (Fe,M) O3 (M= Ti and Cr) thin films by chemical solution depositionmethod. The XRD and Raman analysis showed polycrystalline filmwith no impurity or segregated phase. Electrical studies showed de-creased leakage current with enhanced dielectric, and ferroelectricsproperties. Thus the B-site substitution by Ti and Cr improves vari-ous properties of BiFeO3.

Electronic & Magnetic Materials: Interfacesand Defects in Functional Oxides

Functional Oxides: Thin FilmsRoom: 319Session Chairs: Siu-Wai Chan, Columbia University; Paul Voyles,University of Wisconsin, Madison

8:00 AMNanoscale Control of an Interfacial Metal-Insulator Transition atRoom Temperature (Invited)J. Levy*, C. Cen, University of Pittsburgh, USA; S. Thiel, C. W. Schneider, K.E. Andersen, J. Mannhart, University of Augsburg, Germany; C. Hellberg,Naval Research Laboratory, USA

Here we report the creation and erasure of nanoscale conducting re-gions at the interface between two insulating oxides, LaAlO3 andSrTiO3. Using voltages applied by a conducting atomic force micro-scope (AFM) probe, the buried LaAlO3/SrTiO3 interface is locallyand reversibly switched between insulating and conducting states.Persistent field effects are observed using the AFM probe as a gate.Patterning of conducting lines with widths ~3 nm, as well as arrays ofconducting islands with densities >1014 in-2, is demonstrated. Thepatterned structures are stable for >24 hours at room temperature.Computations were performed at the DoD Major Shared ResourceCenters. This work was supported by DARPA DAAD-19-01-1-0650,the DFG (SFB 484), the EC (Nanoxide) and the ESF (THIOX).

8:40 AMGrowth, relaxation mechanisms, and properties of complextitanate thin films (Invited)P. Salvador*, P. Fisher, H. Du, S. Havelia, S. Wang, M. De Graef, M.Skowronski, Carnegie Mellon University, USA

Using examples taken from the family of complex titanates, the fac-tors that control materials design using thin film deposition are dis-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 164

Wed

nes

day

AM

www.matscitech.org 165

cussed. Three areas related to extended defects or interfacial phenom-ena will be discussed. Electron diffraction was used both in-situ andex-situ to understand the phase formation and relaxation mecha-nisms during the growth of ((Ba,Sr)O)m(TiO2)n films, includingBa0.6Sr0.4TiO3 of various orientations. The phase competition be-tween the pyrochlore and the (110) layered perovskite structure in theRE2Ti2O7 family (RE = rare-earth) will be explored; using electronmicroscopy we demonstrate that a new third crystal structure com-petes in stability during thin film growth. Finally, the growth ofAETi2O5 films (AE = Ba or Sr) will be discussed with respect to theformation of single-phase films or films that phase separate intoAETiO3 and TiO2. The entire Ba1-xSrxTi2O5 series was grown and theirstructural / dielectric properties were measured and will be discussed.

9:40 AMInfluence of a Ferroelectric Substrate on the PhotochemicalProperties of Titania Thin Films (Invited)G. Rohrer*, N. Burbure, P. Salvador, CMU, USA

This study is motivated by the idea that the efficiency of hydrogengeneration by metal oxide photocatalysts might be improved by cre-ating spatially distinct sites for oxidation and reduction on the cata-lyst surface. In this work, dipolar fields from BaTiO3 substrates wereused to create preferential sites for oxidation and reduction on TiO2thin film surfaces. The surfaces are then used to photochemically re-duce Ag+ (or oxidize Pb2+) from aqueous solutions. Scanning poten-tial microscopy and atomic force microscopy are used to map thelocal surface potential and the distribution of reaction products.AFM imaging revealed that reaction products formed on the TiO2surface in patterns consistent with the domain structure of the ferro-electric substrate. It is concluded that dipolar fields from the ferro-electric substrate influence charge carrier transport in the film andspatially localize the reaction products.

10:20 AMRole of Oxide-Semiconductor Interfaces on Materials Properties(Invited)R. Droopad*, Freescale, USA

Oxides on semiconductors are becoming important as an enablingtechnology for the integration of oxide based electronics with matureexisting semiconductor applications. In general oxides possess anumber of functionality which in addition to gate dielectric applica-tions includes the emerging field of multiferroic oxides for non-volatile memory, as well as a variety of sensors. Integration of suchdevices with standard Si-based electronics together with the need fora replacement gate dielectric for Si CMOS devices has been the thrustfor the development of epitaxial oxides on semiconductors. Success-ful growth of oxides on silicon was accomplished through the controlof interfacial kinetics layers using molecular beam epitaxy that has yetto be replicated by other growth techniques. In addition, a process forunpinning the Fermi level of compound semiconductor using oxidesis being pursued with the aim of integrating these high mobility ma-terials as alternative channels materials in future Si-CMOS devices.

11:00 AMObservations & Simulations of resistance switching in oxide thinfilm heterostructuresS. Choi*, J. Meador, K. Jiang, M. Noman, R. Hussin, J. A. Bain, M.Skowronski, P. A. Salvador, Carnegie Mellon University, USA

Many metal/oxide/metal heterostructures exhibit characteristic re-sistance states between which they can be reversibly switched. Wehave developed a quantitative model that provides a description ofthe physical nature of this phenomenon. In experiments, I-V charac-teristics of metal/SrZrO3/SrRuO3 structures were studied using vari-ous metal contacts. The effects of top metal electrodes suggest thephenomena is related to oxygen vacancy motion in response to elec-tric fields as well as to the electrode’s chemical affinity to oxygen.Based on such observations, a basic switching model is proposed and

tested using computational simulations. In the model, the Poissonand transport equations were solved numerically for steady-state dis-tributions of electrical and ionic carriers, and a kinetic barrier forionic motion is introduced to realize bi-stability. The results showthat the model provides a quantitative description of switching thatcorresponds closely to the physical effects observed.

11:20 AMElectro-resistance and Ionic motion at Schottky InterfacesW. Jiang*, Carnegie Mellon University, USA; R. Hussin, Carnegie MellonUnivsersity, USA; M. Skowronski, Carnegie Mellon University, USA; J.Bain, Carnegie Mellon Univsersity, USA; P. Salvador, Carnegie MellonUniversity, USA

The electro-resistance effect was investigated using Pt/(001)SrTiO3-xheterojunctions. The as-deposited junctions exhibit Schottky behav-ior. At large forward biases (~15 V) the junctions switch and exhibitleakage currents (in reverse or small forward bias) that are increasedby several orders of magnitude and bulk-limited currents (at largeforward bias) that are decreased by a factor of 10. These I-V charac-teristics are consistent with the creation of a thin (~1 nm) highly re-sistive layer at the interface owing to ionic motion. The increasedleakage current arises from a decreased effective barrier height owingto the voltage drop across the thin insulating layer (through whichelectrons can tunnel). Under large forward biases, the series compo-nent of this highly resistive layer reduces the overall bulk-limited cur-rent. This electro-resistance is consistent with the motion of ionizedoxygen vacancies in an electric field, which is captured by transienteffects observed in low temperature (≈85K) I-V measurements.

11:40 AMDiffusion Controlled Solid State Reactions in the CoO-MgO-TiO2 SystemS. Reddy*, IBM, USA; D. Lewis, Rensselaer Polytechnic Institute, USA; B.Sundlof, IBM, USA

Microstructural development during solid state reactions in multi-component oxides are, in general, controlled by interdiffusion ofcations. In the (Co-Mg-Ti-O) oxide system, there are three interme-diate “line” compounds, which are: (i) Spinel phase, (Co,Mg)2TiO4;(ii) Ilmenite phase, (Co,Mg)TiO3; and (iii) Pseudo-brookite phase,(Co,Mg)Ti2O5 phase. The term “line” compound refers to the nar-row homogeneity range of the compound in terms of (Co+Mg)/Tiratio. The oxygen sub-lattice in these compounds is rigid and reac-tions occur by diffusion in cation sub-lattice under chemical poten-tial gradients. This paper examines the development of microstruc-tures and growth of intermediate compounds by counterdiffusion ofcations in both (CoO-TiO2) and (CoO-MgO-TiO2) oxide systems.The reaction zone is studied by electron microscopy and compositionanalysis by EPMA. The results are rationalized by consideration ofcrystal structures and relative diffusion rates of each of the intermedi-ate compounds.

Electronic & Magnetic Materials:International Symposium on AdvancedDielectric Materials & Electronic Devices

Advancement in Dielectric Materials Room: 317Session Chair: Rick Ubic, Boise State University

8:00 AMResidual Stress Effects on Fine Grain and Nanograin BariumTitanate Ceramics (Invited)I. Chen*, University of Pennsylvania, USA

Residual stresses arise when the grain size of barium titanate is toosmall to support strain-compensating domains. Although the Devon-shire phenomenological model has been used to assess the residual

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 165

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania166

stress effects, no rigorous stress estimate was made in previous analy-ses. Here we treat each grain as a misfitting spherical inclusion in anelastic matrix of an average dielectric constant, and solve the elastic-dielectrically coupled problem due to inclusion’s ferroelectric transi-tions following Devonshire’s model. Inclusion’s dielectric response toan external field then determines the average dielectric constantwithin the self-consistent-method (SCM) scheme. The resulting di-electric-temperature spectrum, in turn, provides the basis for incor-porating the interaction energy to account for the residual stress ef-fect on low-temperature (t/o and o/r) transitions. The implication ofthis analysis and the unresolved issue (the suppressed dielectric con-stant in the nanograin regime) will be discussed.

8:40 AMGrain Boundaries: Innocent or guilty? Are they Responsible forCausing Loss in Microwave Ceramics? (Invited)N. Alford*, J. Breeze, Imperial College London, United Kingdom

Microwave dielectric ceramics are used by most of the world’s popu-lation every second of the day. We use them in all manner of elec-tronic components notably in our mobile phones and in the mobilephone base stations. They are used as resonators that make up the fil-ters and they are used as dielectric antennas in the phones. One of thekey properties is the dielectric loss and this affects the performance –efficiency, power consumption, signal quality etc. Grain boundariesin polycrystalline microwave dielectric ceramics have long been sus-pected of increasing dielectric loss. In this talk we examine the differ-ence in microwave loss between single crystals and polycrystalline ce-ramics and describe a novel experiment aimed at interrogating theloss of a single grain boundary. We measure the sensitivity of a singlegrain boundary in an MgO bi-crystal to the polarisation of an appliedmicrowave field as a function of temperature.

9:20 AMTowards effective zero-index materials: reduce lossesL. Chen*, Nanyang Technological University, Singapore

The stacking of layers with alternate positive and negative index re-veals a zero effective index materials in theory. Most of these so-called‘zero index’ structures were discussed in an ideal case, which meanslosses were omitted. In fact, the unavoidable losses in most materials& structures will destroy and reduce this effect in a serious manner. Inthis talk, we report a three-layer stacking of positive and negativeindex material which obviously provides a zero-average-index mate-rial in a restricted condition, which also reveals a new band calledzero-equivalent-index. We will also pose a new design of stacking lay-ers using the non-linear positive index material and linear negativeindex material to diminish losses.

Synthesis and Properties of Thick and Thin FilmsRoom: 317Session Chair: Rick Ubic, Boise State University

10:00 AMNew Low Dielectric Loss LTCC Green Tape SYSTEM (Invited)K. M. Nair*, K. W. Hang, M. F. McCombs, K. E. Souders, E.I. duPont deNemours & Co., Inc., USA; S. C. Beers, E.I. duPont de Nemours & Co. Inc, USA

Low Temperature Co-fired Ceramic (LTCC)System has become amajor technological advancement in the high frequency applicationof consumer, military , telecommunications and automotive elec-tronic devices because of its low electrical resistance at high frequen-cies; its compatibility to low-cost silver conductors; its feasibility tominiaturization; the ease to incorporate buried resistors & capacitors;and its long term reliability. In this work, new low dielectric lossLTCC systems consisting of tapes, conductors, resistors, and capaci-tors are examined for the effects of chemistry, processing conditions& processing latitude, microstructure, dielectric properties and relia-bility of gold, silver and mixed metal systems. We also demonstratethe composite of tape system with different dielectric constants to

allow the circuit designers to “mix and match” and incorporate differ-ent functions and also a new system for “Self Constraining PressureLess Assisted Sintering” (SCPLAS).

10:40 AMDesign of Wireless LTCC Devices (Invited)J. Jean*, W. Lo, National Tsing Hua University, Taiwan

Wireless communication systems demand materials and processesthat can meet the requirements of shrinking circuit dimension, highlevel of passive integration, exceptional high frequency performance,excellent reliability, quick prototype turnaround times and low cost.Low-temperature cofired ceramics (LTCC) with high electrical con-ductivity metallization such as Cu and Ag has been identified to be anenabling solution for these challenges. In this presentation, design ofRF circuits, materials and processes for fabrication of miniaturizedLTCC devices and front-end modules will be discussed.

11:00 AMBuried Capacitor Materials For LTCC DevicesK. M. Nair*, M. F. McCombs, M. A. Skurski, T. P. Mobley, E.I. duPont deNemours & Co., Inc., USA

One aspect of miniaturization of electronic circuits is integration ofdifferent functional units within LTCC devices. Incorporation of dis-similar materials such as resistors and capacitors within LTCC offersbenefits compared to other technologies such as printed circuit boardtechnology. Buried bypass capacitor with high dielectric constant tomaintain a constant supply of voltage to the IC is an example. Thepresent paper describes capacitors based on high dielectric constantmaterials of X7R & COG characteristics, circuit design and processused to incorporate such functions within Dupont 951 and low di-electric loss 943 LTCC Green tape systems. Process includes both“plate-type” and “via-fill type” buried capacitors

11:20 AMVertically aligned nanocomposite films: their strain control andelectrical propertiesH. Yang, Los Alamos National Lab, USA; P. Zerrer, University of Cambridge,United Kingdom; H. Wang, J. Yoon, Texas A&M University, USA; A. Fouchet,Y. Yu, M. G. Blamire, J. L. MacManus-Driscoll, University of Cambridge,United Kingdom; Q. Jia*, Los Alamos National Lab, USA

Vertically aligned heteroepitaxial nanocomposite films provide a newdesign paradigm to produce novel functionalities that cannot be ob-tained in individual constituents. In this presentation, we show thatspontaneously ordered structures can be achieved in our designed com-positions.We further demonstrate that the strain states in the compositescan be manipulated by selecting appropriate elastic modulii phases. As arepresentative system, we show self-assembled (BiFeO3)0.5:(Sm2O3)0.5(BFO:SmO) nanocomposite films deposited on (001) SrTiO3 and Nb-doped SrTiO3 substrates by pulsed laser deposition. The BFO and SmOdomains have grown alternately and are vertically aligned with an aver-age column size of 10 nm. We will compare the dielectric properties ofBFO:SmO nanocomposite films with those of pure BFO and SmO thinfilms and discuss the effect of the interfacial area and the strong out-of-plane strain on the dielectric properties of BFO films.

11:40 AMCharacteristics of Alkoxy-Derived TiO2 Arrays Fabricated byNanoimprint MethodK. Kato*, K. Tanaka, K. Suzuki, National Institute of Advanced IndustrialScience and Technology, Japan; T. Morimoto, N. Tsutsui, Ites Co. Ltd., Japan

Periodic structure in which the periodicity is identical to the wave-length of light has much attractive attention for the application to op-tical devises as photonic crystals. TiO2 is one of interesting materialswith high refractive indices as well as high dielectric constant. In thispaper, characteristics of sub-micrometer TiO2 arrays which were fab-ricated by the nanoimprint method are discussed. The precursorfilms were deposited on glass substrates by spin-coating the chemi-

001_271.MST_Abstract.4th 9/3/08 3:07 PM Page 166

Wed

nes

day

AM

www.matscitech.org 167

cally-modified titanium isopropoxide solution. The plastic mold,which was developed by the photolithography, was pressed on theprecursor films and then lift-off after a brief heat treatment at 200C.Resultantly, TiO2 pillars with height and diameter of sub-microme-ters were lined periodically. The structure and properties of the sub-micrometer arrays were characterized comparatively with the alkoxy-derived flat films. The arrays heated at 700C were a single phase ofanatase and showed high transparency.

12:00 PMLow-temperature Fabrication of Highly Loaded Dielectric Filmsfor 3D Integration (Invited)J. Kim*, H. Kim, E. Koo, Y. Yoon, H. Shin, Korea Institute of CeramicEngineering & Technology, South Korea

Ceramic-organic composite thick films over 50 vol. % of dielectricpowder loading has been fabricated at the temperatures lower than300°C using several processing technologies. The objective of thischallenge is to overcome the genetic obstacles of conventional ceram-ics as well as organic technologies in ceramic packaging. The ceramictechnology has been confronted with severe shrinkage, brittleness andhigh temperature processing. The organic based, i.e. PCB technologywith FR-4 epoxy also was not free from low dielectric properties andreliability issues, especially at the RF and microwave applications. Inthis work, ink-jet printing, wet process, and aerosol depositionmethod were used in order to form a highly loaded powder packing inthe thick film bed, and then low loss organic resins were infiltratedinto the dielectric powder packing layer followed by thermal treat-ment under 300°C for completely hermetic monolith film.

Environmental & Energy Issues: Ceramicsand Glass for Waste Minimization,Stabilization, and Disposition

Waste Glass Chemistry and PropertiesRoom: 326Session Chairs: Kevin Fox, Savannah River National Lab; FabienneRaszewski, Savannah River National Lab

8:00 AMAccelerated Processing of SB4 and Preparation for SB5 Processingat DWPFC. C. Herman*, Savannah River National Laboratory, USA

The Defense Waste Processing Facility (DWPF) initiated processingof Sludge Batch 4 (SB4) in May 2007. SB4 was the first DWPF sludgebatch to contain significant quantities of HM or high Al sludge. Ini-tial testing with SB4 simulants showed potential negative impacts toDWPF processing; therefore, Savannah River National Laboratory(SRNL) performed extensive testing in an attempt to optimize pro-cessing. SRNL’s testing has resulted in the highest DWPF productionrates since start-up. During SB4 processing, DWPF also began incor-porating waste streams from the interim salt processing facilities toinitiate coupled operations. While DWPF has been processing SB4,the Liquid Waste Organization and the SRNL have been preparingSludge Batch 5 (SB5). SB5 has undergone low-temperature alu-minum dissolution to reduce the mass of sludge for vitrification andwill contain a small fraction of Purex sludge. A high-level review ofSB4 processing and the SB5 preparation studies will be provided.

8:20 AMConstraint Evaluation on Hanford HLW Glass PropertiesD. Kim*, J. Vienna, V. Jain, Hanford Tank Waste Treatment andImmobilization Plant Project, USA

Hanford high-level tank waste (HLW) will be separated into low-ac-tivity and high-activity waste fractions which will each be vitrified toglass waste forms. To ensure the processability and product quality,several constraints are to be placed on the HLW melter feed. The con-

straints include: viscosity, electrical conductivity, crystallinity at950°C, product consistency test response, toxicity characteristicleaching procedure response, waste loading, melting rate, and variouscomponent concentration limits. The rationale for limit selection willbe described. These limits have varying impacts on the amount ofglass to be produced at Hanford. The impacts on glass amount will besummarized.

8:40 AMCompositional and Kinetic Drivers for Nepheline FormationF. C. Raszewski*, K. M. Fox, D. K. Peeler, Savannah River National Lab, USA

The chemical durability of high-level nuclear waste glasses can be sig-nificantly reduced by nepheline crystallization. Precipitation ofnepheline is of particular concern when processing waste that con-tains high concentrations of alumina and soda. The objective of thisstudy is to determine the influence of both composition and kineticson the formation of nepheline in matrix of glass compositions. Char-acterization of the glasses includes scanning electron microscopy(SEM), differential scanning calorimetry (DSC), infrared (IR) spec-troscopy and X-ray diffraction (XRD).

9:00 AMNepheline Crystallization in High-Level Waste GlassK. M. Fox*, D. K. Peeler, T. B. Edwards, J. D. Newell, Savannah River NationalLaboratory, USA

The chemical durability of high-level nuclear waste glasses can be sig-nificantly reduced by nepheline crystallization. Precipitation ofnepheline is of particular concern when processing waste that containshigh concentrations of aluminum and sodium. A nepheline discrimi-nator is typically used to predict the formation of nepheline based onglass composition. However, the discriminator can be conservative de-pending on glass composition. It also does not take into account all ofthe species, such as calcium and boron, that are thought to influencenepheline formation, nor heat treatment conditions. A series of simu-lated high-level waste glasses covering a range of nepheline discrimi-nator values with varying concentrations of calcium and boron oxideshave been fabricated and characterized to better elucidate the influ-ence of these compounds, as well as thermal history, on suppression ofnepheline crystallization. The potential inhibition mechanisms andtheir effects on glass durability will be discussed.

9:20 AMEffect of compositional changes on the structure andcrystallization tendency of a borosilicate glass containing MoO3M. Magnin*, S. Schuller, CEA, France; D. Caurant, O. Majérus, C. Mercier,CNRS, France

In borosilicate glasses, molybdenum combined with other elementssuch as alkali and alkaline-earth elements may form crystalline molyb-dates during melt cooling, among which sodium molybdate, Na2MoO4,is water-soluble. The solubility limit of MoO3 was found to be 2.5mol%in the simplified SiO2–B2O3–Na2O–CaO glass at about 1300°C. HigherMoO3 concentrations induced phase separation and crystallisation ofNa2MoO4 and CaMoO4. This phenomenon occurs for a cooling rate of103°C/min. To determine the environment of molybdenum in the glass,95Mo, 23Na MAS NMR spectroscopies and μRaman were implementedon a glass series with variable R concentrations ratio,R=[CaO]/([CaO]+[Na2O]) and with a fixed MoO3 amount (2.5mol%).Slow cooled glasses were characterized by XRD, SEM to determine theimpact of Na+ and Ca2+ on the molybdate crystalline phases.

10:00 AMVitreous Waste Forms for a Mixed Cs/Sr/Ba/Rb Waste Stream withCharge CompensationJ. Ryan, J. Crum, D. Strachan, J. Vienna*, Pacific Northwest NationalLaboratory, USA

A series of aluminosilicate glasses were produced containing up to 45wt% of simulated alkali and alkaline earth waste elements. A matrix

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 167

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania168

with key compositional variables including Al2O3 and alkali addition(type and amount) was developed and glasses were melted. Each re-sultant glass was tested for glass formation characteristics, crys-tallinity (amount and phases), density, and durability. Upon decay,cesium and strontium transmute to barium and zirconium, respec-tively, leading to a change in stable valence state from +1 or +2 to +2or +4. This change may have an affect on the stability of glasses, andmay result in the production of soluble and toxic metallic barium.Each glass contained enough Fe3+ or Sn4+ to allow the daughterproducts to remain structurally bound in their preferred oxidationstate after decay of Cs and Sr.

10:20 AMThe Immobilisation of a Chloride Containing Actinide WasteSurrogate into Calcium Aluminosilicate GlassesJ. M. Schofield*, P. A. Bingham, R. J. Hand, University of Sheffield, UnitedKingdom

This study focuses on the immobilisation of a chloride containing ac-tinide waste surrogate into a calcium aluminosilicate glass. CaCl2 hasbeen used as an initial model waste stream, substituted on a mole formole basis for CaO into a base glass with nominal composition (mol%) 51.4 CaO - 7.17 Al2O3 - 41.43 SiO2, and melted at 1450 oC for 3hours. Studies have also been undertaken using a fully-simulatedwaste stream consisting of (mol%) 93.3 CaCl2 - 5.9 HfO2 - 0.7 Sm2O3,substituted as above, for CaO. Initial results, obtained via semi-quan-titative EDS, suggest a surrogate waste loading limit of ~15 mol%,with ~75 atom% Cl- retention during vitrification. The durability ofthe base glass composition, obtained using a modified ASTM PCT-Bmethod, is ~ 9×10-3 - 5×10-4 g m-2 day-1. The use of such glass compo-sitions has the potential to decrease the level of off-gas treatment thatis required for any vitrification process for high chloride contentwastes.

10:40 AMHigher Waste Loading Glasses for Enhanced DOE High-LevelWaste Melter Throughput StudiesF. C. Raszewski*, T. B. Edwards, D. K. Peeler, Savannah River NationalLaboratory, USA

This task is aimed at proof-of-principle testing and the developmentof tools to improve waste loading and melt rate, which will lead tohigher waste throughput. A test matrix of 22 glasses has been devel-oped to gain insight into specific technical issues that could limit theability of glass formulation efforts to target higher waste loadings forfuture sludge batches at the Defense Waste Processing Facility(DWPF). Glass systems exhibiting waste loadings that are restrictedby liquidus temperature predictions, high Al2O3 content and con-straints associated with coupled operations (TiO2 solubility, low fritand homogeneity) were chosen for this study. Results of the liquidustemperature measurements and product consistency tests will be dis-cussed, as well as the identification of any crystalline phases.

11:00 AMProperties of Higher Waste Loading, High-Level Radioactive WasteGlassesA. L. Youchak*, J. C. Marra, D. K. Peeler, T. B. Edwards, Savannah RiverNational Laboratory, USA

The Defense Waste Processing Facility (DWPF) at the Savannah RiverSite (SRS) is vitrifying high-level radioactive waste (HLW) through aJoule heated melter. Currently, glass is processed to contain 34-38weight % HLW. Recent efforts at SRS have evaluated increasing wastethroughput by increasing the waste loading of the glass through theimplementation of cold crucible induction melter (CCIM) technol-ogy. Simulated nuclear waste glasses have been fabricated with higherwaste loadings in mind (45-55 wt %) and their properties measured.Properties such as durability, liquidus temperature, viscosity and ho-mogeneity were crucial when identifying the feasibility of achievinghigher waste throughput as well as a stable waste form. Multiple frits

were identified to achieve at least 50 wt % waste loadings and retainprocessing and product quality constraints.

11:20 AMMelting of Simulated Hanford HLW Glasses – A CompositionVariation StudyV. Jain*, Hanford Tank Waste Treatment and Immobilization Plant Project,USA; K. Matlack, I. Pegg, Catholic University of America, USA; I. Joseph,Energy Solutions, USA; L. Petkus, J. Vienna, Hanford Tank Waste Treatmentand Immobilization Plant Project, USA

The compositions of Hanford high-level wastes vary over a relativelybroad range. A scoping study was undertaken to start evaluating theimpact of gross chemical changes on processability and melt rate.This study was designed to vary key glass components – Al2O3 (2 to13 wt%), B2O3 (4 to 15), Fe2O3 (4 to 16), Li2O (0 to 4), MnO (0 to8), Na2O (9 to 20), SiO2 (33 to 51), SrO (0 to 9), ZrO2 (0 to 10), mi-nors (Cr2O3 to 0.6, K2O to 2.5, La2O3 to 1.2, TiO2 to 1, and ZnO to4). The ranges of key glass properties were also tested – viscosity, elec-trical conductivity, and temperature at one volume percent crystals.The steady state glass processing rate ranged from 450 to 2150Kg/(m2-d). Processing rates increased with alkali and boron contentsas well as lower melt viscosity. Some feeds required the addition of re-ductants to obtain reasonable melting behavior. This paper presentsthe results of melting tests and composition impacts on melting rate.

Environmental & Energy Issues: EnergyMaterials

Other Energy Materials IIIRoom: 327Session Chairs: Fatih Dogan, Missouri University of Science andTechnology; Masanobu Awano, National Institute of AdvancedIndustrial Science and Technology

8:00 AMPreparation of high-Jc MOD-YBCO films for fault current limiters(Invited)M. Sohma*, W. Kondo, K. Tsukada, I. Yamaguchi, T. Kumagai, T. Manabe, K.Arai, H. Yamasaki, National Institute of Advanced Industrial Science andTechnology, Japan

Metalorganic deposition (MOD) is one of the most promising meth-ods to prepare various functional oxide films, since the method hasan advantage of precise composition control and potential for manu-facturing complex-metal-oxide films such as high-temperature su-perconducting (HTS) YBCO. This technique can be applied to large-area HTS films at low cost necessary for a resistive-type fault currentlimiter (FCL) which limits the prospective fault current when a faultoccurs. In our MOD-YBCO procedure a fluorine-free metal acety-lacetonate-based solution including stoichiometric ingredients isspin-coated onto the CeO2-buffered sapphire substrates. After thecoating the organic components decompose to amorphous materialby prefiring and then, by high-temperature heat treatment, to thecrystallized YBCO phase. This paper presents the preparation ofhigh-critical-current-density (Jc=4MA/cm2 at 77K) MOD-YBCOfilms having an area of 3 x 21 cm and the possibility of practical use ofa FCL module using the films.

8:40 AMDevelopment of Advanced Ceramic Reactors (Invited)T. Suzuki, Y. Fujishiro, T. Yamaguchi, K. Hamamoto, M. Awano*, NationalInstitute of Advanced Industrial Science and Technology, Japan

Ceramic electrochemical SOFC-type reactors are expected for theirhigh-efficiency. Development of manufacturing process technologyfor sub-millimeter tubular cells as well as for arrangement and inte-gration of such cells in the micro level will enable us to realize highperformance cube-type cell stack modules applicable for the electro-

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 168

Wed

nes

day

AM

www.matscitech.org 169

chemical reactor modules with power density more than 2kW/litter,and with thermal durability for rapid temperature operation, de-signed for auxiliary power units (APU) and small stationary powergeneration systems. We have achieved cell performance of 1 W/cm2power density at 570oC, which is the world’s highest power densityamong SOFCs with ceria based electrolytes. Furthermore, cell bun-dles and stacks were successfully fabricated with performance of over2-3W per a cubic size by operation under 600 oC. This work was sup-ported by NEDO as part of the Advanced Ceramic Reactor Project.

9:20 AMElectrochemical Cell for Removing NOx and Soot from DieselExhaustK. B. Andersen, Z. He, R. M. Larsen Werchmeister, L. Keel, F. B. Nygaard, M.Menon*, K. K. Hansen, Risø National Laboratory for Sustainable Energy,Technical University of Denmark, Denmark

Removal of pollutants such as NOx and soot from diesel exhaust isimperative for minimizing health hazards and increase the quality oflife, especially in large cities. Here we present a design for an electro-chemical cell for removal of both soot and NOx. These cells are multi-layered structures of an electrolyte (eg. doped ceria) sandwiched be-tween electrodes (eg. (La,Sr)MnO3). These structures weremanufactured by laminating tapes prepared by tape casting and sin-tering. The performance of these structures were characterized bysingle cell testing. The conversion of NOx was characterized as a func-tion of microstructral variables, such as, number of layers, porosityand composition by measuring cyclic-voltametery. Finally, the per-formance of these cells were also characterized in a system with realdiesel exhaust.

Thermoelectric MaterialsRoom: 327Session Chairs: Ali Sayir, NASA Glenn Research Center; Fred Dynys,NASA Glenn Research Center

10:00 AMCombination of Ceramic Electrochemical Reactor andThermoelectric Ceramic Module for Enhanced DeNOx Propertyby Using Wasted Heat Energy (Invited)Y. Fujishiro*, K. Hamamoto, T. Suzuki, T. Yamaguchi, M. Awano, NationalInstitute of Advanced Industrial Science and Technology, Japan

The electrochemical cells for de-NOx reaction reveal properties wellsuited to present applications, in particular their very low consump-tion of electrical power for operation. The concept of operating thedevice for environment purification without energy consumptionthrough improvement and assembly of the ceramic materials as a de-vice has been finally realized by an interactive ceramic reactor com-posed of the de-NOx electrochemical cell with a power module ofthermoelectric energy conversion ceramics. Thermoelectric conver-sion by ceramics as high as 40mW/cm2 is obtained for a temperaturedifference of 500 oC. Compound module has proved to generate 300mW power. NOx decomposition properties of 20% without any exter-nal power supply has been achieved continuously through supplyingelectrical current from the thermoelectric power module to the de-NOx cell by energy conversion from wasted heat of the exhaust gas.

10:40 AMMulti-Functional Materials for Aeronautical Power Generation(Invited)F. Dynys, A. Sayir*, NASA Glenn, USA; A. Sehirlioglu, Case Western ReserveUniversity, USA

Integration of energy harvesting materials for power generation andstorage devices into aeronautical structures is a new approach inweight reduction. Thermoelectric materials that exhibit good energyconversion efficiency and load bearing properties are sought for hy-personic vehicles. The high temperature durability of silicon based al-

loys and semiconducting ceramics make them potential thermoelec-tric materials. Directional solidification of silicides is being exploredto produce microstructures with enhanced mechanical propertiesand reduced thermal conductance. Thermoelectric properties ofphase separated SnO2-TiO2 are being evaluated. Thermal conduc-tance in the range of 2 to 5 W/mK have been achieved in both siliconbased alloys and SnO2-TiO2. Thermoelectric and elastic properties ofboth systems will be reported as a function of temperature.

11:20 AMSelf-Powered Wireless Sensors (Invited)F. Dynys*, A. Sayir, NASA Glenn, USA

NASA’s integrated vehicle health management (IVHM) program of-fers the potential to improve aeronautical safety, reduce cost and im-prove performance by utilizing networks of wireless sensors. Devel-opment of sensor systems for engine hot sections will providereal-time data for prognostics and health management of turbo-en-gines. Sustainable power to embedded wireless sensors is a key chal-lenge for prolong operation. Harvesting energy from the environ-ment has emerged as a viable technique for power generation.Thermoelectric generators provide a direct conversion of heat energyto electrical energy. Micro-power sources derived from thermoelec-tric films are desired for applications in harsh thermal environments.Silicon based alloys are being explored for applications in high tem-perature environments containing oxygen. Chromium based p-typeSi/Ge alloys exhibit Seebeck coefficients on the order of 160 micro-V/K and low thermal conductance of 2.5 to 5 W/mK. Thermoelectricproperties of bulk and thin film silicides will be discussed.

Environmental & Energy Issues: Fuel Cells:Materials, Processing, Manufacturing,Balance of Plant and Systems Operation

Cell and Stack Component Materials IIRoom: 325Session Chairs: Ayyakkannu Manivannan, National EnergyTechnology Lab; Abdul-Majeed Azad, University of Toledo

8:00 AMElectrical Stability of Refractory Sealing Glass with CoatedMetallic Interconnect Materials (Invited)Y. Chou*, J. Stevenson, J. Choi, S. Weil, P. Singh, Pacific Northwest NationalLaboratory, USA

Pacific Northwest National Laboratory has been developing variousmaterials including sealant, coating, and electrodes for SOFC applica-tions. In this work we conducted material evaluation of a refractorysealing glass and a coated metallic interconnect. Two metallic inter-connect squares were sealed with refractory sealing glass, and testedthe high-temperature electrical resistance for stability in a dual envi-ronment at 800-850C. The metal coupons were aluminized to mini-mize oxidation and were compared to plain metal coupons. Resistiv-ity versus time will be reported together with the interfacialcharacterization to assess the integrity of coating as well as the sealingglass for SOFC.

8:40 AMElectrical Properties of a Sealing Glass Exposed to Electric Fieldfor SOFC applicationS. K. Singh*, R. N. Singh, University of Cincinnati, USA

The sealing material in Solid Oxide Fuel Cell is always in contact withthe stack components, electrolyte (YSZ), and interconnect material(stainless steel or other alloys), during operation at 8000 C. A highelectrical resistance is one of the important requirements for sealingmaterial. A small current leakage can lead to short circuit and candamage the cell, which eventually degrade the cell efficiency. The elec-trical behavior of silicate based glass seal is characterized and long

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 169

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania170

term stability is evaluated. The dc measurement of glass as well asglass in contact with interconnect is evaluated for longer time at 8000

C. These results will be presented.

9:00 AMThermal Cycle Reliability of Glass/Ceramic Composite Gas SealingMaterialsS. Suda*, M. Matsumiya, K. Kawahara, K. Jono, Japan Fine CeramicsCenter, Japan

Micro SOFCs require sealing materials that can be fused at a relativelow temperature and possess high reliability under cyclic thermalload to realize high efficient power generation. We have developedgas-tight seals that were composed of glass precursors and ceramicprecursors. Amorphous Na2O-SiO2 spherical particles (NS particles)and amorphous SiO2 particles (S particle) were synthesized by sol-gelmethod, and flexible sheets containing NS and S particles were pre-pared by tape-casting method. After fused at 800°C with porousLSCF cathode materials, thermal cycle sealing tests were investigatedat the temperature range of 400-650°C. Gas sealing for soda limeglass, which were used as a reference, were deteriorated after 45 hunder cyclic thermal loading, but the composite materials showed nodeterioration for more than a month. An adequate ratio of NS parti-cles to S would result in highly durable gas-tight sealing materials.

9:20 AMExperimental Study of Aging and Self-healing Behavior ofGlass/Ceramic Sealant Used in SOFCW. Liu*, X. Sun, Pacific Northwest National Lab, USA

High operating temperature of solid oxide fuel cells require thatsealant must function at high temperature between 600o and 900oCand in the oxidizing and reducing environments of fuel and air. In thispaper, experiment tests were implemented to investigate the effect ofaging time and self-healing behavior of the glass ceramic sealant usedin SOFCs on its mechanical properties. With longer heat treatment oraging during operation, further crystallization may reduce the resid-ual glass content and boost the ceramic crystalline. Meanwhile, themicro-damage induced by the cooling down process from the operat-ing temperature to the room temperature degrades the mechanicalproperties of the glass/ceramic sealant. During the reheat of the SOFCto the operating temperature, the self-healing characterization of theglass/ceramic sealant restores the mechanical performance

10:00 AMDevelopment of Seal-Less Solid Oxide Fuel Cells at Siemens(Invited)C. Lu*, Siemens Energy, USA

Siemens has pioneered the development of seal-less solid oxide fuelcells (SOFC) and demonstrated reliable and robust SOFCs over sev-eral years of operation for stationary applications. Siemens now is fo-cusing on the development of High Power Density (HPD) cells byrevolutionizing cell designs and utilizing advanced materials andprocesses. Results of the latest development in seal-less SOFCs atSiemens will be presented.

10:40 AMDevelopment of a Reactive Air Coating Process for Glass-MetalJoining in SOFC StacksJ. Choi*, S. K. Weil, Pacific Northwest National Laboratory, USA

SOFC stacks operate at high temperature (700-800°C) and the as-sociated interconnect component is typically made from ferriticstainless steel (SS) and hermitically sealed to adjacent components,such as the ceramic cell, often with a glass-ceramic sealant. In thisway the durability of the entire stack is dependent on the robust-ness of these glass-SS joints. As will be presented, a newly devel-oped coating process was used to modify the surface of the SS, by

forming specially shaped protrusions that enhance the chemicaland mechanical stability of the glass/metal interface and therebytoughen the joint with respect to easy crack propagation. Varioussizes and shapes of these protrusions were prepared in an effort tocharacterize the new process and corresponding mechanical testswere performed to quantitatively evaluate the effect of this surfacemodification on the joint strength. In addition, thermal cycle test-ing was conducted to evaluate joint durability under typical useconditions.

11:00 AMReaction Sintering of Yttria Stabilized Zirconia Anodes viaNickel OxideJ. White*, I. E. Reimanis, Colorado School of Mines, USA; G. W. Coors, S.Menzer, CoorsTek, USA

The influence of NiO on the stabilization of 8 mol% Y2O3 stabi-lized ZrO2 (8YSZ) anodes is examined through systematic experi-ments in which the amount of NiO and Y2O3 is varied for severaldifferent ZrO2 powders. Electron microscopy and x-ray diffractionare used to characterize the percentage of phases present and cal-culate lattice parameters. Quench studies have been conducted toanalyze high temperature solubility of NiO in monoclinic zirco-nia. It is shown that NiO has a beneficial effect in that it acceler-ates the stabilization of cubic ZrO2 during heat treatment. Themechanism controlling this accelerating effect on 8YSZ stabiliza-tion is discussed.

11:20 AMLow temperature sintering and proton conductivity of Yb-doped BaZrO3J. Park*, J. Lee, H. Lee, B. Kim, Korea Institute of Science and Technology,South Korea

The acceptor doped BaZrO3 is the promising candidate because of itshigh proton conductivity but, it has the poor sinterability. Earlierstudies on the sintering of the doped BaZrO3 reported that the4mol% ZnO addition decreased the sintering temperature down to1300oC. However, the added ZnO acted as the proton trap in the inte-rior of grain and decreased the bulk proton conductivity of Y-dopedBaZrO3. Therefore, the CuO instead of ZnO was added in the Yb-doped BaZrO3 as the sintering aids, and by the 2mol% addition of theCuO the fully dense sample could be acquired at 1500oC which waslower about 200oC than that of the unmodified Yb-doped BaZrO3.The effects of CuO addition on the bulk proton conductivity and thegrain boundary proton conductivity were discussed on the basis ofdefect structures and microstructures and were compared with theeffects of ZnO addition.

11:40 AMDiffusion study of a novel glass seal with metallic interconnect andshape memory alloy for solid oxide cellsM. Mahapatra*, K. Lu, W. Reynolds, Virginia Polytechnic Institute and StateUniversity, USA

Glass and glass-ceramic seals are the most desirable candidate toseal solid oxide cell components such as anode, cathode, and inter-connect. In this work, the diffusion of a novel glass seal into Crofer22 APU interconnect alloy and shape memory alloy has been stud-ied. Diffusion couples of glass and different alloys are made at950°C for 30 min dwell time in an argon atmosphere. The diffusioncouples are heat treated at 800°C for different times up to 100 hrs.Glass bonds well with both Crofer 22 APU interconnect alloy andshape memory alloy. The cross sections of the diffusion couples arecharacterized by SEM and EDS analyses. Only 2-3 μm interfacezone is observed. No severe reaction between glass and the alloys isdetected. The proposed glass shows great potential as solid oxidecell seals.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 170

Wed

nes

day

AM

www.matscitech.org 171

Environmental & Energy Issues: GreenTechnologies for Materials Manufacturingand Processing

Environmentally Benign Process IRoom: 323Session Chairs: Alex Cozzi, Savannah River National Lab; AllenApblett, Oklahoma State University

8:00 AMOn the Great Pyramids of Egypt and Sustainable BuildingMaterials (Invited)M. Barsoum*, Drexel University, USA

Recently we presented compelling microstructural evidence thatsome of the blocks of some of the pyramids of Egypt were - as pro-posed more than 20 years ago by Davidovits - cast. The cementingphase is not an alkali alumino-silicate, but rather a combination ofamorphous silica, and amorphous Ca and/or Mg-silicates. This inturn implies that the raw materials for the binding phases used werediatomaceous earth and lime and/or calcined dolomite. In this talk,this and other evidence, will be presented. Our efforts in recreatingthis reconstituted limestone – that, in some cases, has survived ex-posed to the elements for 4,500 years as an outer casing – will be re-viewed. That this building material has a small CO2 footprint, re-quires nothing more sophisticated that what was available millenniaago and lasted as long as it has is humbling but also exciting in itspotential.

8:40 AMAlkali-activated Cements based on Diatomaceous EarthE. Jud Sierra*, S. Miller, P. Narang, A. Moseson, M. W. Barsoum, DrexelUniversity, USA

Alkali-activated cements are an environmentally friendly alternativeto Portland cement due to their small carbon footprint. The objectiveof our work is the recreation of reconstituted limestone based on thetechnology used in outer casing stones from the Great Pyramids inEgypt to produce low cost, sustainable cements for developing coun-tries. Compressive strength is aimed at 20 MPa as measured in sam-ples from the pyramids that have cured for over 4000 years. Prelimi-nary results of diatomaceous earth activated with lime and comparedto compositions activated by sodium hydroxide show compressivestrength of > 5 MPa after 7 days. The microstructure is further char-acterized by X-ray diffraction, SEM/EDS, FTIR, and MAS-NMR, andshows a cementing phase of Ca-Silicates.

9:00 AMSilica-based Nanostructures and the Pyramids of EgyptM. W. Barsoum*, E. Jud Sierra, A. Sakulich, A. Moseson, Drexel University,USA; K. J. MacKenzie, Victoria University of Wellington, New Zealand; S. C.Vogel, L. L. Daemen, Los Alamos National Laboratory, USA

The cementing phase, mainly consisting of Ca-silicates, CS, of aninner casing limestone from Khufu as analyzed by SEM/EDS has a mi-crostructure that is identical to the outer, previously identified as syn-thetic, Ca-phosphate layer of the same limestone. The same cement-ing phase was found in an outer casing of another pyramid. 29Si and43Ca MAS NMR spectra show that Si is present mainly as SiO2, withsmaller peaks corresponding to Si-OH and CS, whose 43Ca spectrumis comparable to an amorphous CS hydrate. Neutron vibrationalspectroscopy confirms the presence of water, which appears as a lig-and in a well-defined structure and stoichiometry. Several frequenciescharacteristic of silanol groups appear in the spectrum, compatiblewith the presence of a hydrated silicate. These findings corroboratethe synthetic nature of these stones and may, once reproduced, proveto be a useful building material with a small CO2 imprint.

9:20 AMAlkali-Activated Cements As A Sustainable Building Material; CaseStudy of Slag Cement using Design Of ExperimentA. J. Moseson*, A. Sakulich, A. Curtin, E. Jud, M. W. Barsoum, DrexelUniversity, USA

Globally the Portland cement industry is one of the largest producerof CO2 emissions. Alkali-activated concretes (AACs) are an attractivealternative, with comparable performance and cost, but little CO2emissions. In this talk, our recent progress on the development of aniron slag AACs will be discussed, including XRD and SEM analysis,and application of Design of Experiment (DOE). Using DOE, a sta-tistical method to develop and analyze empirical work, has yieldedvaluable models of the system. This allows, amongst other things, abetter understanding of mixture component interactions, and theability to run virtual experiments. We focused on iron slag activatedby natron (sodium carbonate), with a limestone aggregate, and devel-oped a formula that cures at room temperature to a 40 MPa compres-sive strength that in bulk could cost on the order of $30 USD/ton. Theuse of AACs in the Egyptian Pyramids, a major source of our inspira-tion, will also be discussed.

10:00 AMGreen Process for Separation of Metals from Sulfide OresA. Apblett*, K. Barber, Oklahoma State University, USA

The production of metals or metal oxides from sulfide ores is prob-lematic since it entails “roasting” of the ores to convert them to oxidesthat can subsequently be reduced to metals. Roasting produces largequantities of sulfur dioxide and other pollutants that must betrapped. We are developing an alternative approach in which the sul-fide ions are oxidized to sulfur or sulfur oxyanions leading to solubi-lization of the metal ions. Treating the solution with potassiummolybdate then precipitates the metals. Subsequent washing withpotassium hydroxide yields the solid metal hydroxides and a potas-sium molybdate solution that may be reused. Overall, the processavoids the generation of gases that contribute to acid rain and pro-duces components of fertilizer as the main by-products. The applica-tion of the process to a variety of ores will be discussed.

10:20 AMExploiting Hall-Petch Strengthening for SustainabilityR. Heard*, Carnegie Mellon University, USA; U. Erb, University of Toronto,Canada; G. Palumbo, Integran Tecnologies Inc., Canada

Sustainable engineering embraces conservation of materials and energy.Nanomaterials, and in particular nano-metal materials, can play a sig-nificant role in reducing the negative impact that we have on our planetthrough the exploitation of properties derived from the Hall-Petch rela-tionship. Designers can reduce section mass in moving parts thus en-hancing energy efficiency and reducing greenhouse gas emissions (e.g.,MetaFuse™ nanometal-polymer hybrids for lightweight automotivecomponents). They can also design for longer product lifecycles, thusreducing scrap rates and landfill requirements. Moreover, Hall-Petchstrengthening of environmentally benign alloy systems can lead to thereplacement of incumbent toxic materials and processes (e.g., nano CoPcoatings as a replacement for hexavalent chromium plating; nano-cop-per coaxial composite wire for the replacement of toxic Beryllium al-loys). In this paper, an overview is provided of these “sustainable” nano-materials which are rapidly finding market acceptance.

10:40 AMEffect of Bismuth on the Dry Machinability of Al-12 Si AlloysP. Chen*, A. T. Alpas, University of Windsor, Canada

Aluminum adhesion to the tool during dry machining of cast Al-Sialloys is a major problem. The machinability of Al-Si alloys can beimproved by adding low melting point elements during casting. Inthis work, the effects of bismuth addition on the mechanical proper-ties and dry machinability of an Al-12% Si alloys have been investi-gated. Different strontium /bismuth ratios (0.05 to 0.4) and cooling

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 171

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania172

rates were used to refine the Si morphology. The T6 treatment of anAl-12.7Si-0.1Sr-0.5Bi alloy resulted in a tensile strength of 258.1 MPa,and a Charpy impact energy absorption of 3.4 J/cm2. With increasingSr/Bi ratio, the fracture surfaces exhibited fewer fractured particlesand a higher frequency of dimples indicating an increase in ductility.Dry orthogonal turning tests, performed at a cutting speed of0.43m/s and feed rate 0.16 mm/rev, indicated that Bi enhanced thediscontinuous chip formation.

11:00 AMNovel process development with continuous casting and preciseforging for Al-Si alloys to produce an engine pistonO. Umezawa*, Yokohama National University, Japan; H. Takagi, Toyama AlloyCo., Japan; T. Sekiguchi, Miyamoto Industry Co., Japan; T. Yamashita,Toyama Alloy Co., Japan; N. Miyamoto, Miyamoto Industry Co., Japan

An adiabatic mold continuous casting method has been developed toproduce a billet with smooth surface for hyper-eutectic Al-Si-Cu-Mg-(Ni, Fe, Mn) alloys. Without peering and hot-extrusion processes thecast billet with 83 mm in diameter has been successfully applied towarm forging. Although primary Si crystals and intermetallic com-pounds were mostly refined under high cooling condition in the cast-ing, coalesced Si crystals or compounds were still remained at thecenter part in the cross section. A working and annealing step hasbeen installed due to increase formability of the cast with a modifica-tion of its microstructure. The isothermal forging with greener lubri-cant and precise mold technologies has been developed and a proto-type of motorbike engine piston was produced. It showed an excellentstrength such as fatigue and creep at high temperature (523 and/or573 K). This process may give an up-grade solution to the recycle ofsecondary aluminum alloy.

Environmental & Energy Issues:Thermoelectric Materials: Science,Technology and Applications

Thermoelectric Antimonides, Tellurides, and BoridesRoom: 324Session Chairs: Hsin Wang, Oak Ridge National Lab; Øystein Prytz,University of Oslo

8:00 AMFilled Skutterudites: from single to multiple filling (Invited)W. Zhang*, L. Xi, J. Yang, L. Chen, Shanghai Institute of Ceramics, China; J.Yang, Materials and Processes Laboratory, USA

By using ab initio calculations and thermodynamic analysis, our grouphas made progresses in understanding the filling fraction limit (FFL)for filler atoms in single-element-filled CoSb3. The calculated andmeasured FFLs show good accordance so far. Based on our theory,ultra-high FFLs in a few alkali-metal(AM)-filled CoSb3 have been pre-dicted and then proven by experimentalists. Thermoelectric perform-ance of the AM-filled CoSb3 is shown to be surprising good. Electricalperformance is studied by Boltzmann transport theory under the re-laxation time approximation for acoustic phonon scattering. We foundthat the multiple-element-filled CoSb3 systems with filler atoms beingselected from rare-earth metals (La, Ce, Eu, Yb), alkaline-earth metals(Ba, Sr), and alkaline metals (Na, K), when possessing different reso-nance frequency ranges by categories, may be good for thermal con-ductivity reduction and therefore for TE performance enhancement.

8:30 AMLow and high temperature thermoelectric properties of n-typemultiple-filled skutteruditesX. Shi*, J. R. Salvador, J. Yang, General Motors R&D Center, USA; C. Uher,University of Michigan, USA

n-type CoSb3 based filled skutterudites have good electrical transportproperties with power factor values over 40 micro-W/cm-K2 at high

temperatures. Filling multiple fillers into the crystallographic voids ofskutterudites would help scatter a broader range of lattice phonons,thus result in lower lattice thermal conductivity values. We report onthe thermoelectric properties in n-type multiple-filled skutteruditesystem. The combination of different fillers inside the voids of theskutterudite structure provides enhanced phonon scattering, andconsequently a strong suppression of the lattice thermal conductivityis observed. Very good power factor values are achieved in multiple-filled skutterudite, comparable to single-filled materials. The dimen-sionless thermoelectric figure of merit for n-type filled skutteruditesis improved through multiple-filling in a wide temperature range.

8:50 AMElectrical transport properties for filled CoSb3 skutterudites: atheoretical studyJ. Yang*, General Motors R&D Center, USA

We present ab initio calculations of electrical transport properties forfilled CoSb3 skutterudites. The electronic structure is performed byprojected augmented plane-wave method, and all the systems arestudied in a 2*2*2 supercell of Co4Sb12. The effect on conductionband bottom due to different filler atoms and filling fractions is re-vealed. Electrical transport properties are calculated in the frameworkof the Boltzmann transport theory with the group velocity evaluatedby the momentum matrix method, and a relaxation time for acousticphonon scattering is used. With our implementation, the tempera-ture dependence of Seebeck coefficient, electrical conductivity, andpower factor is studied, and good agreement with experimental datais obtained. Optimal filling fraction for n-type filled CoSb3 skutteru-dites and related compounds is revealed.

9:10 AMThermoelectric properties of the ββ-Zn4Sb3 compoundE. Flage-Larsen*, O. Løvvik, University of Oslo, Norway

In the recent years the β-phased Zn4Sb3 compound has received at-tention due to the promising thermoelectric properties at moderatetemperatures. This is mainly due to an exceptional low thermal con-ductivity. However the true nature of the structure is still unknown.First principle calculation of the thermoelectric properties are herepresented within the framework of density functional theory. We cal-culate the Seebeck coeffcient based on Boltzmann theory within therelaxation-time approximation for the different proposed structures.

10:00 AMIn search of the elusive high-ZT: Thermoelectric performance of(AgSbTe2) (PbTe)m through variations in synthesis andstoichiometry (Invited)F. Drymiotis*, D. Thompson, T. Drye, T. Tritt, Clemson University, USA

The LAST ((AgSbTe2)(PbTe)m ) compound is one of the most prom-ising thermoelectric material for high-temperature applications. Un-fortunately, reproducibility of the originally reported high ZT still re-mains elusive. Intrigued by the complexity of the structure and thepotential for technological applications we decided to perform a sys-tematic study of the compound. Our goal is to establish a method ofpreparation which will consistently yield high-ZT values. We will bepresenting our data on LAST compounds with m ranging from 0.5 to18. Specifically we will be discussing the variations in thermopower,resistivity and thermal conductivity, as we vary the synthesis proce-dure and the stoichiometry.

10:30 AMThermoelectric Properties of Quaternary MolybdenumAntimonidesT. Holgate*, S. Zhe, T. Tritt, Clemson University, USA; H. Xu, H. Kleinke,University of Waterloo, Canada

We have successfully demonstrated that Te-substituted Mo3Sb7 mayreach high ZT values at elevated temperatures. With this contribu-

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 172

Wed

nes

day

AM

www.matscitech.org 173

tion, we report on our ongoing attempts to further optimize the ther-moelectric performance, for example by varying the Sb:Te ratio andadding different cations.

10:50 AMSeebeck’s Effect on Amorphous-Crystalline Transition Zone andAmorphous-Crystalline ThermocoupleM. Finkel*, DAATH-Scientific Center, USA; J. Chen, Temple University, USA;D. Finkel, DAATH-Scientific Center, USA

The Thermo-Electric Seebek’s phenomenon on Amorphous-Crys-talline transition Zone is being studied for various alloy composi-tions. One of the simple methods proposed for Amorphous-Crys-talline thermocouple (ACT) preparation involves crystallization ofthe melt-spun amorphous ribbon on the part of its length, using aheterogeneous temperature field. A sharp natural amorphous-crys-talline transition zone, formed in such conditions, plays a role of athermocouple hot junction. The magnitude and sense of Differentialthermo-power, α, depends on alloy composition. A thermocouplemade from as-cast Co-Fe-Si-B alloy demonstrates constant α=8.1μV/K in the temperature range from 293 to 593 K. An ACT can beeasily stabilized by anneals. Several other methods are proposed forthermocouple fabrication. It is suggested that, for low and moderatetemperatures, ACT could be technically and economically more ad-vantageous than crystalline thermocouples. Patent is issued.

11:10 AMThermoelectric Properties of FeSb2 Single CrystalQ. Jie*, R. Hu, C. Petrovic, P. Khalifah, Q. Li, Brookhaven National Lab, USA

Recently, the colossal Seebeck coefficient(S) was reported in singlecrystal FeSb2, a type of Kondo insulator and strongly correlated elec-tron system with low charge carrier density, where localized d or fstates hybridize with conduction electron states leading to the forma-tion of a small hybridization gap that may result in high S. In this talk,we report our investigation on thermoelectric properties of largeFeSb2 single crystals, grown by flux method. Electrical resistivity(ρ),S, and thermal conductivity(κ) along b/c-axes were measured in both0 and 9T magnetic field. κ is generally lower in magnetic field. Ataround 10K, S reaches -6000μV/K along b-axis, and -2000μV/K alongc-axis, respectively, but is lower than what was reported by A. Bentienet al. Magnetic field has strong effect on ρ and S. Transverse field de-presses S at temperature between 5K and 15K, but gives rise to highermagneto-resistance. The interplay of the electron correlation andthermoelectric property in this material will be discussed.

11:30 AMThermal expansion behaviors of LAST and LASTT thermoelectricmaterials as a function of temperatureF. Ren*, B. D. Hall, E. D. Case, E. J. Timm, Michigan State University, USA; R.M. Trejo, E. Lara-Curzio, Oak Ridge National Laboratory, USA

LAST (Pb-Sb-Ag-Te) and LASTT (Pb-Sb-Ag-Te-Sn) materials exhibitgood thermoelectric (TE) properties, which can be potentially ap-plied in waste heat recovery. Thermal expansion behavior of TE ma-terials is critical to the fabrication and performance of TE devices,which are subject to temperature gradients and/or thermal cyclingunder in-service conditions. In this study, the coefficient of thermalexpansion (CTE) of LAST and LASTT fabricated by both casting andhot pressing were determined via thermomechanical analysis be-tween room temperature (RT) and 673 K. Also,the lattice parametersof LAST materials were calculated from high temperature XRD pat-terns obtained between RT and 623 K. The mean CTE values rangedbetween 20 x 10-6 K-1 and 23 x 10-6 K-1. While the temperature de-pendent CTE of Ag0.43Pb18Sb1.2Te20 composition increased withincreasing temperature, a peak between RT and 450 K in the CTEversus temperature curve was observed for the Ag0.86Pb19SbTe20concentration.

Fundamentals & Characterization: ACerSSosman Award Symposium: KineticEngineering of Interfacial TransportProcesses

Robert B. Sosman SessionRoom: 406Session Chair: Gregory Rohrer, Carnegie Mellon University

8:00 AMFirst Principles Modeling of Diffusion Kinetics and Sliding ofAlumina Grain Boundaries: Implications for Oxide Growth andCreep (Invited)E. A. Carter*, Princeton University, USA

We present results of first principles density functional theory (DFT)calculations used to test hypotheses about dopants that may extendthermal barrier coating (TBC) lifetimes. Hindering alumina growthin the TBC is thought to be critical. Empirically, it is known that TMssuch as Pt, Hf, and Y improve TBC stability, although their mecha-nism of action is not well characterized. Some of these TMs (e.g., Y)segregate to grain boundaries in alumina, and it has been suggestedthat alumina growth may be inhibited by their presence. We presentpredictions of the behavior of the alumina Σ11 || tilt grain boundary.As it is thought that growth of alumina is controlled by Al and O dif-fusion at grain boundaries, we explore the energy landscape for segre-gation, diffusion, and sliding of this grain boundary for Al, O, and avariety of metal dopants, yielding new insights into growth and creepinhibition.

8:40 AMOxygen and Aluminum Diffusion in αα-Al2O3: How much do wereally understand? (Invited)A. H. Heuer*, Case Western Reserve University, USA

The major diffusion processes in α-Al2O3 are reviewed, includingoxygen and aluminum lattice diffusion, Doxy and DAl, respectively,oxygen grain boundary diffusion, Db-oxy, and pipe diffusion, Dp.Their relevance to creep of Al2O3 and oxidation of Al2O3 scale-forming alloys are considered. The answer to the question in title is“not a great deal”. Eight major issues are identified for future research:i)What is the nature of the “buffering” that appears to control Doxy?ii)What process(es) are occurring during annealing that eliminatenon-Fickian behavior when measuring Doxy? iii)How should themeasured activation energies for Doxy be interpreted? iv)Have all thedefect types involved in oxygen diffusion been identified? v)Doesoxygen diffusion occur by an interstitialcy mechanism? vi)What is theorder of magnitude of DAl/Doxy? vii)What is the order of magnitudeof Db-Al /Db-oxy? viii)It appears that the activation energy for Db-oxy is greater than that for Doxy. How should this be understood?

9:40 AMAn Overview of Normal versus Abnormal Grain Growth (Invited)A. Rollett*, Carnegie Mellon University, USA

This presentation will attempt an overview of our understanding ofnormal versus abnormal grain growth. Long standing theories ofgrain growth in 2D have been supplemented by new theory in 3Dgrain growth such as MacPherson-Srolovitz theory. This has raisedinteresting questions about how we measure objects in 3D. Turning toabnormal grain growth, it is clear that this is a common phenomenonwith multiple causes. Small differences in stored energy can occur be-tween grains from either variations in dislocation content, for exam-ple. Abnormal growth has long known to be facilitated by variationsin mobility on a theoretical basis but recent work by Harmer’s grouphas shown how transitions in grain boundary structure can give riseto such variations. Dispersed second phase particles have long been

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 173

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania174

known to be associated with abnormal growth but making a quanti-tative connection has been hard to demonstrate. Nevertheless, theoryand simulation point to some possible mechanisms.

10:20 AMGrain boundary films in silicon nitride (Invited)M. J. Hoffmann*, University of Karlsruhe, Germany; P. F. Becher, Oak RidgeNational Laboratory , USA; R. L. Satet, University of Karlsruhe, Germany

Si3N4 ceramics are densified by liquid phase sintering to obtain a mul-tiphase microstructure with in-situ grown elongated grains that areseparated by intergranular films (IGF) formed by the sintering aids.The paper will review the current understanding of the impact ofIGFs on microstructure and properties. Growth anisotropy is shownto be a function of the rare earth elements used as sintering aids incombination with MgO or Al2O3. Experimental observations will bediscussed in terms of a different adsorption behaviour of the rareearth on Si3N4 basal and prism planes. The mechanical behaviour hasbeen proven to be not only a function of grain size and aspect ratiobut to a large extend to depend on the characteristics of the IGFs.Data of fracture toughness and strength show a clear dependency onthe composition of the IGF and raise the issue that the toughest ma-terial is not the strongest. R-curve measurements show that the R-curve rises slower but to higher levels for the weaker materials con-taining larger rare earth elements.

11:00 AMInterface Stability: The Variety and Conditions for ComplexionTransitions (Invited)W. C. Carter*, M. Tang, Massachusetts Institute of Technology, USA

armer, his colleagues, and other groups are collecting data that areconsistent with the hypothesis that grain boundaries undergo struc-tural and chemical transitions; these grain-boundary transitions arenot phase transitions per se, because confusion may arise if one as-cribes phase-like character to them. Thus, a new term, “complexions”has been coined to identify the various equilibrium states in a crystalthat is constrained to have a misorientation. In addition, Shen et alhave identified a number of physical and processing implications ofcomplexion transitions. We will describe a large set of intensive andgeometric parameters upon which complexion transitions depend.Many, but not all, of these conditions were anticipated by Gibbs,Smith, and Cahn. The complexion transitions include, but are notlimited to, complete wetting, facetting/roughening, premelting, aswell as the chemical and structural transitions analyzed by Tang et alusing KWC method.

Fundamentals & Characterization: Discoveryand Optimization of Materials throughComputational Design

Multiscale Materials Design IIRoom: 303Session Chairs: Carelyn Campbell, National Institute of Standardsand Technology; Zi-Kui Liu, Pennsylvania State University

8:00 AM3D Materials by Design (Invited)G. B. Olson*, Northwestern University, USA

Under the ONR/DARPA “D3D” Digital Structure consortium pro-gram, a systems approach to computational design of hierarchicallystructured materials is extended to explicit 3D microstructural designemploying a suite of multiscale tomographic characterization tools toinform a new generation of 3D microstructural simulation tools. Theapproach combines materials science, applied mechanics, and quan-tum physics in addressing multiscale particle distributions governingthe strength, toughness and fatigue resistance of ductile alloys. The

toolset is being actively applied to high performance steel designs fora range of Navy applications.

8:40 AMProgress in MatCASE: Automation and New Capabilities (Invited)Z. Liu*, The Pennsylvania State University, USA

The framework of the MatCASE (Materials Computation and Simula-tion Environment) project supported by the National Science Founda-tion integrates first-principles calculations, multi-component modeling,multi-phase phase-field simulation, and finite element analysis to com-putationally predict phase stability, phase transformation and materialsproperties [J. Comput-Aided Mater. Des.,Vol.11, 2004, 183–199]. In thispresentation, some recent developments will be discussed, includingprediction of self and impurity diffusion coefficients by first-principlescalculations, automation of thermodynamic modeling, simulation ofnucleation, and the establishment of the Center for Computational Ma-terials Design (CCMD) supported by NSF, national labs, and industrycompanies [Proceedings Education and Professional Development, Ma-terials Science & Technology 2006, Cincinnati, Ohio, 2006, pp. 111-118].

9:40 AMMulti-Million Atom Simulations of Strain and ElectronicStructure with NEMO 3-D (Invited)G. Klimeck*, N. Kharche, M. Usman, Purdue, USA; T. B. Boykin, Universityof Alabama in Huntsville, USA

At the nanometer scale the concepts of device and material meet anda new device is a new material and vice versa. While atomistic devicerepresentations are novel to device physicists, the semiconductor ma-terials modeling community usually treats infinitely periodic struc-tures. NEMO 3-D bridges the gap and enables 52 million atom elec-tronic structure simulations of quantum dots, quantum wells,nanowires, and impurities with relevant device dimensions. Two ex-amples will illustrate the importance of atomistic disorder in realisti-cally large systems. For strained Si quantum wells on wafer-miscutSiGe substrates valley splitting is computed as a function of magneticfield. For InAs quantum dots embedded in an InGaAs strain reducinglayer on top of a GaAs substrate NEMO 3-D can model the non-linearoptical transition energy dependence as a function of In-concentra-tion. Both simulation sets match experimental data without adjust-ment to the NEMO 3-D material parameters or device geometries.

10:20 AMDiffusion Mobility Descriptions in Ordered Phases: Applicationsin Ni-base Superalloys and Bond Coat Materials (Invited)C. Campbell*, National Institute of Standards and Technology, USA

Aluminde containing bond coats are key components that enable gas-turbine engines to operate at higher temperatures. The stability of cur-rent bond coat materials must be improved to increase current operat-ing temperatures. This requires modeling the interdiffusion reactionsbetween the Ni-base superalloy substrate and the bond coat materialduring processing and service. Diffusion mobility descriptions for theordered fcc (γ′-L12) and ordered bcc B2 phases are essential for model-ing these interdiffusion reactions. The phenomenological model de-veloped by Helander and Ågren is used to determine the diffusion mo-bility descriptions for the γ′ and B2 phases in the Ni-Al-Cr system. Thedescriptions reproduce the experimental data for tracer diffusivities,interdiffusion coefficients and the activation energies for the γ′ and B2phases. These mobility descriptions are then used to predict the mi-crostructure evolution in model diffusion couples of γ+γ′/B2+γ alloys.

11:00 AMThermodynamic Stability of Materials: Integration of Finite-Temperature Ab Initio Methods and CALPHAD Modeling(Invited)R. Arroyave*, Texas A&M University, USA

Historically, the CALPHAD approach has been limited by the qual-ity/quantity of the data used for parameter optimization. This diffi-

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 174

Wed

nes

day

AM

www.matscitech.org 175

culty can been overcome by using data derived from ab initio calcula-tions. In this talk, recent work on the prediction of finite temperaturethermodynamic properties will be discussed. An analysis of the con-tribution of different DOF (including anharmonicity) to the phasestability of the different ordered phases studied will be presented. Ex-amples will be presented to provide an idea on the degree of uncer-tainty of the predictions. Examples will be presented in which thesetools have been applied to generate CALPHAD models for systemswith insufficient experimental data, or to refine models with suspectexperimental data. Finally, a speculative approach towards the predic-tion of melting temperatures of intermetallics through calculations ofthe properties of the solid phases and its implication in CALPHADmodeling will be presented.

11:40 AMMultiscale Computational Design of Ductile Refractory Alloys forModern Fossil Energy ApplicationsM. Gao*, O. Dogan, P. King, National Energy Technology Lab, USA

Refractory alloys are promising high-temperature materials for mod-ern fossil energy applications (e.g. oxy-fuel gas turbines). In additionto high strength and high-temperature stability, ductility and corro-sion resistance against oxidation are critically important for this classof materials. In this talk, an integrated approach to design advanced re-fractory alloys will be presented. The strategy is to combine first-prin-ciples calculations, computational thermodynamics and kinetics, andmesoscale finite element simulation. Key physical, thermodynamicand elastic properties for a range of binary, ternary and higher-ordersystems will be computed from first-principles calculations in the firstplace. The results will be used as key guidance for experimental designand data input for CALPHAD-type thermodynamic database develop-ment. Microstructure optimization including micro-texture via FEMand key experiments to validate computation will also be presented.

Fundamentals & Characterization: FailureAnalysis for Problem Solving

Tools and TechniquesRoom: 304Session Chairs: Larry Hanke, Materials Evaluation and Engineering,Inc.; David Norfleet, Engineering Systems Inc.; Craig Clauser, CCECI

8:00 AMForget Success, Lets Talk About Failure! (Invited)A. B. Tanzer*, Lehigh Testing Laboratories, Inc., USA

While “follow the recipe” approaches to failure investigations providestructure and some good general rules, engineers who use these ap-proaches often end up focusing on unimportant findings while miss-ing entirely the clues which identify failure mode, mechanism, and/orroot cause. This talk will emphasize how the failure analyst has to beflexible in applying different possible perspectives to meet investiga-tion goals. Examples of some of the critical thinking skills requiredwill be illustrated in case studies of real-world failures.

8:40 AMMethod for Cross Section Preparation for SEM Using a BroadArgon Ion Beam (Invited)N. Erdman*, C. Nielsen, R. Mierzwa, R. Campbell, JEOL USA, Inc, USA

Examination of cross sections provides essential information aboutfeatures and properties that impact performance and reliability.However, mechanical preparation methods present several problems:uneven polishing; embedded particles of hard abrasive; strain on thepolished surface; f) fine features smeared; g) preserving water-solublephases. Ultra microtome and Focused Ion Beam (FIB) are used, butrequire high skill and can lead to artifacts. A new specimen prepara-tion apparatus, the Cross Section Polisher (CP) utilizes a broad argonion beam that eliminates problems with the conventional methods.

The main advantages of the CP include: high quality cross sections ofsoft and hard materials, minimum distortion of the polished surface,grain contrast revealed clearly and easily, large cross section areascompared to FIB, and no particle embedding. Various examples willbe shown of CP application for sectioning semiconductors, soft ma-terials, paper, biological materials, metals etc.

9:00 AMFailure Analysis with Electron Microscopes and the new SiliconDrift Detectors (Invited)M. Kelsey*, Bruker AXS Inc., USA

In the field of Microanalysis, a new detector technology for EnergyDispersive Spectroscopy (EDS) has evolved. The Silicon Drift Detec-tor (SDD) offers many advantages of the traditional Lithium DriftedSilicon (Si(Li)) detector including speed, resolution and maintenancerequirements. It now makes it possible to rapidly analyze forensicallythe residue materials due to crime, contamination or chemicalchanges. This talk will explain the differences in these technologiesand how SDD makes it possible to do in minutes what used to takehours with the older Si(Li) detectors.

9:20 AMRadiography in Failure Analysis: X-ray vs. Neutron (Invited)D. Norfleet*, D. Alexander, Engineering Systems Inc., USA; J. Gauthier, NrayServices Inc., Canada; C. Cherry, YXLON International Inc., USA

Radiography is an important tool in the non-destructive evaluation ofcomponents subject to quality control and failure analysis. The abilityto “see” inside a component permits evaluation of imperfections or de-fects that might otherwise only be found through random destructivetesting of a component. Likewise, for complex mechanisms and com-ponents that might otherwise be disturbed upon disassembly. In thispresentation, two forms of radiography are discussed and compared.The more commonly used type employs X-rays; electromagnetic radia-tion whose attenuation is proportional to electron density of the mate-rial being examined. Less commonly used are neutrons whose attenua-tion is dependent on the nuclear properties of the target. In importantways, the two techniques complement one another. Additionally, thispresentation will describe the state of the art in another aspect of radi-ography – computer aided tomography or CAT scanning. Exampleswill be provided demonstrating the latest capabilities of this technique.

10:00 AMCorrelating microstructure and crystallography with fracturetopography in titanium alloys (Invited)A. L. Pilchak*, R. E. Williams, A. Bhattacharjee, The Ohio State University,USA; A. H. Rosenberger, Air Force Research Laboratory, USA; J. C. Williams,The Ohio State University, USA

High strength titanium alloys can have a range of complex microstruc-tures. As a consequence, the fracture surfaces of these alloys resultingfrom either monotonic or cyclic loading can be very challenging to in-terpret. Understanding the relationship between fracture topographyand microstructure, however, constitutes an important link betweenmaterial performance and microstructure. To this end, we have em-ployed a range of techniques, including electron backscatter diffractionand focused ion beam milling, designed to provide a direct correlationbetween fracture topography and microstructure. This talk will de-scribe these techniques and use examples to illustrate their usefulnessin interpreting the influence of microstructure on the fracture behaviorof titanium alloys. This work has been supported by the Office of NavalResearch under grants N00014-05-1-0504 and N00014-06-1-0089.

10:40 AMChemical Incompatibility Studies of a Pool Liner SystemK. Steiner*, Wiss, Janney, Elstner Associates, Inc., USA

Chemical incompatibilities of seemingly inert materials can requirerehabilitation of various types of systems. As an example, incompati-ble waterproofing systems were used for a swimming pool, resulting

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 175

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania176

in unsightly staining and a costly rehab of the pool. Simulated expo-sure tests, characterization with optical microscopy, and analysis ofthe components by Fourier transform infrared spectroscopy wereconducted to determine the cause of the staining. The staining wasreproduced in the exposure studies, and the chemical analysis of thewaterproofing systems and of the stains indicated the components re-sponsible. The staining was determined to have been caused by or-ganic components migrating from one system to the other, either re-sulting in the stain directly, or combining with components in theother systems to produce a stain.

11:00 AMQuantitative Microstructural Analysis to evaluate the Strengthand Reliability of CeramicsT. Bernthaler*, A. Nagel, G. Schneider, Aalen University , Germany; M.Hoffman, University of New South Wales, Australia

The brittle nature of ceramics means that their strength and reliabil-ity is dependent upon microstructural defects. This paper presents ameans of addressing the significant challenge of predicting thestrength reliability of ceramic components in a non-destructive man-ner. The presented approach demonstrates the effectiveness and ad-vantages of a ceramographic method, using a high-throughput mi-croscopic and image analysis procedures to visualize and quantifydefect populations in series of alumina ceramics. A model will be pre-sented which links fracture mechanics with quantitative image analy-sis data to predict the characteristic strength and the Weibull modu-lus. The results show a good correlation between mechanical andpredicted strength of 4-point bending samples. Anisotropic defectcharacteristics due to the axial forming process are considered alongwith a description of a bimodal strength distribution.

11:20 AMAdvantages of Low-Voltage SEM for Failure AnalysisL. Hanke*, R. Haase, Materials Evaluation and Engineering, Inc., USA

Scanning electron microscopy (SEM) is a common and essential toolfor failure analysis. Few users, however, take full advantages of the ca-pabilities of the SEM to obtain the best possible data for their analy-ses. One commonly overlooked operating condition that can be veryuseful is low accelerating voltage. Varying the accelerating voltage canresult in significant differences in the images obtained and the resultsof microchemical analyses. Low voltage imaging is especially usefulfor resolving fine features in low-density materials, such as imagingthin films and fractures in polymer materials. This presentation willexplain how accelerating voltage influences the interaction of theelectron beam with the sample in the SEM and varying the voltagecan improve images and analysis results.

Fundamentals & Characterization: Fatigue ofMaterials: Competing Failure Modes andVariability in Fatigue Life

Fatigue of Steels, Nickel and Titanium AlloysRoom: 305Session Chairs: P. Liaw, University of Tennessee; J. Earthman,University of California, Irvine

8:00 AMPerspective on Competing Modes Fatigue Behavior (Invited)G. T. Cashman*, University of Utah, USA

Competing Failure Modes in fatigue refers to the occurrence oftwo failure distributions in an apparent homogenous data set. Thedisparate distributions have been attributed to failures occurringon the surface of test specimens and other failures from sub-sur-face to deeply imbedded sites. Often, when this occurs significantlife differences, by a factor of ten or more have been observed.

Conversely, under different testing conditions, principally temper-ature, failure from these distinct initiation sites yields resultsdemonstrating little or marginal life differences. Competing Modesbehavior has been reported in many steel, nickel-base and titaniumalloys. Given the extent of the occurrence of this behavior it seemsreasonable that a new or at least modified perspective on fatiguebehavior is in order. Discussion will be presented relative to theclassical concept of the endurance limit and how a modified viewis seemingly necessary.

8:40 AMForeign Object Damage and Short Crack Behavior in Ti-6Al-4V AlloyB. Majidi*, Amirkabir Universityof Technology, Iran

High-cycle fatigue (HCF) failures associated with foreign objectdamage (FOD) in turbine engines of military aircrafts have beenof major concern for the aeronautic industry in recent years. Thepresent work is focused on characterizing the effects of FOD oncrack initiation and small crack growth of a Ti-6Al-4V alloy atambient and also elevated temperatures. Results show that thepreferred crack initiation site depends on applied stress and tem-perature. The fatigue crack growth rate is influenced by increasingtemperature, and the FCG rate at 300 °C is higher than that atroom temperature under the same ΔK, whereas this effect forFOD-site initiated cracks is not so remarkable. This observationseems to be due to the effect of stress relaxation at 300 °C. Resultsalso indicate that fatigue crack initiation life (N i ) and fatigue life(N f ) are expressed by three-parameter Weibull distributionfunction.

9:00 AMLow Cycle Fatigue Variability in Single Crystal SuperalloysSolidified with Liquid Metal Cooled and Conventional BridgmanProcessesC. L. Brundidge*, T. M. Pollock, J. Jones, University of Michigan, USA

Factors influencing the fatigue variability of Rene N5 single crystalstested at 538oC (1000oF) have been investigated. The role of coolingrates during solidification has been examined with the use of a liquidmetal cooling (LMC) solidification process in comparison to a con-ventional Bridgman process. Additions of Ta to increase the shearingresistance of precipitates have also been investigated. Increases incooling rates during solidification decrease primary and secondarydendrite arm spacings by as much as 184 microns and 33 microns, re-spectively, and also decrease the size of solidification shrinkage pores.Increases in cooling rates enhance fatigue life by as much as a factor ofseven. Solidification variables had a much stronger influence on fa-tigue life than minor changes in chemistry. The influence of variousfeatures of cast microstructure on fatigue variability will be discussed.

9:20 AMCompeting Fatigue Failure Modes in High Temperature Fatigue ofRené 88DT Nickel-Base Superalloy at 650CP. Chang*, G. T. Cashman, R. Chandran, University of Utah, USA

Competing fatigue failure mechanisms during high cycle fatigue testsof the nickel-based superalloy, René 88DT, at 650C, is examined. Theobjective is to examine how the cleanliness of the material affects thecompeting fatigue failure mechanisms. One group of specimens con-taining purposely-seeded Al2O3 inclusions is evaluated and a secondgroup of coupons prepared from normal production material istested as well. Fatigue specimens with two different test volumes werealso used to examine how the volume of material under fatigue mod-ifies the failure competition between surface and interior initiatedfailures. A complete characterization of size and distributions of in-clusions in the microstructure has also been performed. A statisticalframework is developed to model the connection between inclusiondistribution, failure competition and fatigue life.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 176

Wed

nes

day

AM

www.matscitech.org 177

10:00 AMHigh Stress Fatigue Behavior of Fine Grained Thin Film NickelJ. G. Collins*, C. Muhlstein, Pennsylvania State University, USA

The high stress fatigue behavior of nanocrystalline direct currentelectrodeposited and micrograined pulse electrodeposited thin filmnickel samples was explored for the two different material systems.Tensile tests utilizing a strain rate of 0.003 sec-1 evaluated the me-chanical properties of the films. Incremental step tests were con-ducted at 90% of the yield strength with a strain rate of 0.003 sec-1

and utilized either 20 steps or 30 steps per block. The test was stoppedwhen the material cyclically stabilized. Both the DC electrodepositedand PED nickel cyclically hardened and stabilized after five blocks oftesting, or approximately 20 minutes of testing. Post-fatigue tensiletests demonstrated an increase in tensile strength of 10% comparedto the as-received specimens. DC electrodeposited and PED thin filmnickel specimens reached steady-state fatigue behavior in less than 20minutes when incrementally step tested at their yield strength, result-ing in increased tensile strength and cyclic hardening.

10:20 AMDevelopment of a low cost hold-time fatigue (SPLCF) test systemJ. L. Myers*, B. H. Lawless, W. H. Buttrill, GE Aviation, USA

A historical standard method for performing hold time fatigue orSPLCF (sustained peak low cycle fatigue) tests has been to performthese tests on servo-hydraulic or servo-electric type fatigue systems.The testing cost associated with running these types of tests can beprohibitive for tests that are weeks or months (not days) in duration.Additionally, for long time tests, there are continuing risks of test sys-tem shutdown or calamity due to: a) loss of electrical power, and b)long periods of motionless actuator activity that can ultimately leadto the loss of load control and an invalid test. GE Aviation has devel-oped and patented a unique testing system, which significantly re-duces the costs to perform long-time fatigue testing, and provides anadditional level of fail-safe protection against loss of control. Thiscurrent system is limited to tension only loading due to the construc-tion of most lever-arm creep-rupture machines.

10:40 AMEffect of Alloying on the Elevated-Temperature Fatigue Behaviorof Ti Alloys Reinforced with SiC Fibers or TiB WhiskersW. Chen, J. Quast, C. J. Boehlert*, Michigan State University, USA

The effect of B on the isothermal fatigue behavior of Ti-6Al-4V(wt%)and Ti-6Al-2Sn-4Zr-2Mo(wt.%) at T>400C was evaluated. The Bconcentration ranged between 0-1wt% and the alloys were evaluatedin the as-cast and cast-then-extruded conditions. B additions in-creased the average fatigue lives, and the cast-then-extruded alloys ex-hibited significantly longer fatigue lives than the as-cast alloys. Thiswas partially attributed to the finer alpha-lath width exhibited by thecast-then-extruded alloys. In addition, the out-of-phase (OOP) ther-momechanical fatigue behavior (TMF) of Ti-24Al-17Nb-xMo(at.%)/SiC continuously-reinforced MMCs was evaluated. TheMMCs containing matrices with larger Mo contents exhibited greaterOOP TMF lives. They also exhibited greater creep resistance. S-Ncurves and the microstructure of each material will be presented, andthe fracture and deformation behavior and fatigue-life variability willbe compared.

11:00 AMFatigue properties of pre-FPP (fine particle peening) treated andgas nitrided austenitic stainless steelS. Kikuchi*, Y. Nakahara, Graduate school of Science and Technology, Keiouniversity, Japan; J. Komotori, Keio university, Japan

Nitrided layer is extremely thin due to the existence of passivationfilm at the surface of austenitic stainless steel. In order to encouragethe nitrogen to diffuse into the material, we introduced a fine particlepeening (FPP) treatment before gas nitriding. The effects of pre-FPPtreatment on gas nitriding behavior and fatigue properties of AISI

316 steel were evaluated. Surface microstructures of the FPP treatedspecimens before nitriding were characterized by micro-vickers hard-ness tester, scanning electron microscope (SEM), optical microscope,electron probe micro analyzer (EPMA) and X-ray diffraction (XRD).Rotational bending fatigue tests were carried out. After fatigue tests,fracture surfaces were observed by SEM. Pre-FPP treatment gener-ated the local stratification pattern which has high dislocation densi-ties. Therefore, nitrogen diffused into this unique structure, resultingin increasing surface hardness. And fatigue fracture mechanism wasalso discussed.

11:20 AMElectron Microscopy Analysis of Crack Propagation Behavior ofAluminaH. Matsuo*, K. Ikeda, S. Hata, H. Nakashima, Kyusyu University, Japan

In order to clarify the mechanism of crack propagation of alumina,the direction of crack propagation and fracture surfaces indexes wereinvestigated by electron microscopy techniques. Cracks were propa-gated in mode I loading. Macroscopic features of transgranular cracksin polycrystalline alumina and cracks in singlecrystal alumina wereanalyzed by SEM-EBSD technique. It was revealed that zigzag crackspropagated along the cleavage planes. In addition, length of step-ter-race cracks in singlecrystal alumina was long with decreasing stress.Fracture surfaces in a singlecrystal alumina were observed byHAADF-STEM tomography. It was revealed that fracture surface ofzigzag cracks were composed of flat and uneven fracture surfaces. Theflat fracture surfaces were near the cleavage plane. The uneven fracturesurfaces were introduced near the basal plane. The results indicate thattransgranular crack propagation behavior of alumina depends on thecleavage plane, the basal plane and magnitude of applied stress.

Fundamentals & Characterization:International Symposium on Defects,Transport and Related Phenomena

Defects and Transport in Ceramics IIRoom: 307Session Chairs: Doreen Edwards, Alfred University; Stefan Adams,National University of Singapore

8:00 AMIon transport in oxides investigated by means of current-assistedtracer diffusion and impedance spectroscopy (Invited)J. Fleig*, A. Schintlmeister, M. Gerstl, M. Ahrens, H. Hutter, Vienna Universityof Technology, Austria

Diffusion of tracer ions and subsequent analysis of the profiles by SIMS isa powerful tool for investigating ion transport in the bulk and across in-terfaces of oxides. However, ion exchange at phase boundaries or surfaces(e.g. oxygen incorporation quantified by a k-factor) is often very sluggishand thus high temperatures are frequently required for achieving meas-urable tracer concentrations; shallow tracer profiles are difficult to obtain.In this contribution it is shown how an electric current drastically in-creases the effective ion exchange factor k in tracer experiments and thusenables the preparation of very shallow diffusion profiles at low tempera-tures. A model for quantifying the relation between current density andeffective k factor is presented.The approach is illustrated by several exper-imental examples. Complementary impedance spectroscopic studieshelp in consistently interpreting bulk and interfacial transport properties.

8:40 AMConductivity Behaviour of V2O5 Pressed Bodies and Correlationto the Catalytic BehaviourM. Harth, O. Goerke, D. Habel, H. Schubert*, Berlin University of Scienceand Technology, Germany

V2O5 has been successfully tested for dehydrogenation of propene.The reaction is commonly described by a donation of one oxygen

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 177

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania178

atom from the catalyser surface which reacts with two hydrogenatoms. For reoxidation a redox type reaction is needed which requireselectron mobility. Thus, conductivity measurement were carried outfor pressed bodies of V2O5 and for TiO2, SiO2 and Al2O3 supportedV2O5 in a temperature interval from RT up to 500°C in oxygen, N2and CO. The two characteristic measurements were AC impedancespectroscopy and Hebb-Wagner polarization for electronic contribu-tion. At lower temperatures an activation enthalpy of 0.35eV was ob-served followed by a 0.6 eV region higher than 450°C, probablycaused by the formation of V4+. This reduction coincides with thestart of the catalytic activity. AC and DC conductivity, Measurementon the change of the material stoichometry and catalytic testing willbe reported.

9:00 AMIonic transport in intercalation compounds from first principles(Invited)A. Van der Ven*, The University of Michigan, USA

While much progress has been made in the first-principles predictionof the thermodynamics of solids, predicting kinetics in the solid-stateremains a major challenge. Lithium diffusion in intercalation com-pounds (LixC6, LixCoO2, Li(Ni0.5Mn0.5)O2, LixTiS2) plays an im-portant role in determining the rate capabilities of Li-batteries. Sincethe Li concentration of the cathode material can range from zero tocomplete filling of interstitial sites, Li diffusion occurs predominantlyin the non-dilute regime. Hence, interactions among Li ions becomeimportant and variations in the degree of short and long-range orderaffect dominant hop mechanisms and introduce important correla-tions between successive hops that lead to diffusion coefficients witha strong concentration dependence. In this talk, I will describe howfirst-principles electronic structure methods combined with statisti-cal mechanical techniques from alloy theory have elucidated complexdiffusion mechanisms in intercalation compounds.

10:00 AMBond valence analysis of ionic conductivity in disordered ceramicmaterials (Invited)S. N. Adams*, Nat. University of Singapore, Singapore

Defects and their transport in crystalline or non-crystalline ceramicscan be effectively studied by an augmented bond valence (BV) ap-proach. As an example the conduction mechanism of scandiumtungstate has been studied in detail by in situ XRD methods, imped-ance spectroscopy, molecular dynamics (MD) simulations and ourBV analysis. BV models of ion transport pathways and MD simula-tions accordingly suggest that the diffusing species is the entiretungstate anion. A novel dynamic BV pathway analysis demonstratesthat the hopping (or rather rolling) of WO4

2- defects follows the in-stantaneous diffusion pathways, while the creation of WO4

2- defects isa rare high energy process. Similarly the BV analysis has proven to besuccessful in predicting ionic conductivity including the mesoscopicmultiphase effect in nanostructured interface-dominated materialsor the mixed alkali effect in local structure models for glasses basedon reverse Monte Carlo fits to experimental diffraction data.

10:40 AMImpedance and phase stability studies on the 1-dimensionalconductor AxGa4+xTi1-xO8 (AGTO) (x ~ 0.7, A = Na+, K+, Li+, Ag+, H+)J. W. Amoroso*, D. D. Edwards, Kazuo Inamori School of Engineering atAlfred University, N.Y.S. College of Ceramics, USA

NaxGa4+xTi1-xO8 (NGTO) (x ~ 0.7) is a 1-dimensional conductor dueto its crystal structure. The material is monoclinic and possesses tun-nels running parallel to the unique b-axis which contain and providea path for the mobile sodium ions. The electrical conductivity ofpolycrystalline NGTO ranged from ~10-7 S/cm at 300°C to ~10-3

S/cm at 1000°C. High temperature X-ray diffraction (HTXRD)shows NGTO beginning to form at 950°C and remains stable up to~1200°C. Ion-exchange methods are utilized to replace the sodium in

NGTO with other monovalent ions (K+, Li+, Ag+, H+). The electricalconductivity and phase stability of NGTO and its exchanged analogshas been studied using HTXRD and impedance spectroscopy (IS)under wet and dry atmospheres. Results for the atmosphere and sta-bility measurements are discussed to better understand and explainthe conduction mechanisms occurring within this one-dimensionalconductor.

11:00 AMFrom Weak Electrolytes to Superionic Solids: Discussion of theCoulombic Interaction Potential (Invited)D. S. Mebane*, R. Merkle, J. Maier, Max Planck Institute for Solid StateResearch, Germany

An increase in the conductivity above the ideal behavior as tempera-tures rise toward the melting point is often found in ionic solids. Evenif not ultimately leading to a superionic transition, as is the case forsilver iodide, this conductivity behavior may be seen as a manifesta-tion of an overall attractive defect interaction. In this talk, variousmethods of quantitatively describing the interaction energy are re-viewed, beginning with various descriptions of coulombic interac-tion as developed in the context of liquids. The appropriateness ofthese liquid theories to the solid state is discussed, particularly in lightof the empirical success of a quasi-Madelung approach that leads to acube-root power law in the chemical potential.1-3 1. Hainovsky, N.and Maier, J., Phys. Rev. B 51 (1995) 15789. 2. Maier, J. and Münch,W., Z. Anorg. Allg. Chem. 626 (2000) 264. 3. Merkle, R. and Maier, J.,Z. Anorg. Allg. Chem. 631 (2005) 1163.

11:40 AMAnalytical and Numerical Treatment of Tracer Diffusion in Oxidesfrom a Heterogeneous Thick Film SourceJ. D. McGuffin-Cawley*, Case Western Reserve University, USA

Tracer experiments are standard practice in diffusion studies. Manyparticular solutions to the diffusion equation have been developed topermit calculation of expected concentration profiles for comparisonto experimental data. The advent of ink jet printing and advances indepth profiling technologies have given rise to a new class of experi-ment in which a uniform film of one oxide enriched in tracer is de-posited on a semi-infinite sample of a second oxide. It becomes of in-terest to analyze the cases in which the tracer diffusion coefficients inthe two materials are different. Both closed form solutions and nu-merical modeling results will be presented and compared to pub-lished results for cases where the D(film) is less than, greater than,and equal to D(substrate).

Fundamentals & Characterization: Micro-and Nano- Mechanical Behavior of Low-Dimensional Structures and Materials

Micro- and Nano- Mechanical Behavior of Materials -CeramicsRoom: 308Session Chairs: Xiaodong Li, University of South Carolina; DavidBahr, Washington State University

8:00 AMNanoindentation Behavior of Nanoclay-Zirconia Multilayers andits Implications for Synthesis and DesignZ. Wei, X. Wang, G. Zhang*, Louisiana State University, USA; H. Chen, J. Luo,Clemson University, USA

A new class of nanostructured multilayers consisting of alternatinglayers of ultrathin ZrO2 and exfoliated clay nanoplatelets has beendeveloped via solution-based layer-by-layer deposition and anneal-ing. Nanoindentation testing was conducted on these multilayers pre-pared under different annealing temperature, clay size, exfoliation

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 178

Wed

nes

day

AM

www.matscitech.org 179

method, film thickness, and deposition process to understand theirmechanical properties, structural integrity, and the processing-struc-ture-property relationship. To extract the accurate hardness and elas-tic modulus, we developed a special nanoindentation technique com-bining the DCM and XP loading modes for shallow and deepindentation respectively, and applied the Tuck et al. (2001) and Saha-Nix (2002) models to fit the experimental data. Results reveal the sig-nificant dependence of mechanical properties on synthesis condi-tions. These findings are expected to provide guidance on optimizingthe design and synthesis process of the multilayers.

8:20 AMHardness and deformation mechanisms of Ti3SnC2, a ternarynanolaminate carbideC. Tromas, N. Ouabadi, V. Gauthier, M. Jaouen, S. Dubois*, LaboratoirePHYMAT, France

Hardness and Young’s modulus of Ti3SnC2 [1] has been determinedby nanoindentation. The sample was composed of 80.5% ofTi3SnC2, 16.2% of TiC, 0.3% of FeSn, 0.8% of FeSn2 and 2.2% of Sn.Due to the complex nature of the sample, a statistic analysis has beenperformed over 400 indents, organised in a regular square shapedarray, with a step size of 7μm. A hardness cartography has been estab-lished and superimposed to an optical microscopy image of the sam-ple. In this way, the different hardness values have been related to thedifferent phases. Moreover, hardness has been measured as a functionof the penetration depth. It is demonstrated that the experimentalvariation is related to indentation size effects [2]. Finally, the intrinsichardness value is 9.3 GPa which is larger than other values measuredon ternary carbides. [1] S. Dubois, T. Cabioc’h, P. Chartier, V. Gau-thier and M. Jaouen, J. Am. Ceram. Soc., 90, 8 (2007) 2642. [2] W. D.Nix and H. Gao, J. Mech. Phys. Solids, 46 (3) 1998, 411.

8:40 AMRoom Temperature Creep of Brittle Solids Studied by SphericalNanoindentationS. Basu*, Drexel University, USA; M. Radovic, Texas A&M University, USA;M. W. Barsoum, Drexel University, USA

With the continual shrinkage in the size of devices, dimensions areshrinking and stresses, thermal and other, can become significant. Itfollows that understanding the time dependent deformation, aroundroom temperature, becomes crucial in predicting the failure modesand/or lifetimes of such devices. However, room temperature plasticdeformation of brittle solids and their time dependencies are not eas-ily measured. By converting load/displacement nanoindentation, NI,results to NI stress/strain curves and using a feedback loop we wereable, for the first time, to carry out constant-stress NI experiments onA-plane (11-20) ZnO single crystals and show that creep at roomtemperature follows a power-law, with a stress exponent of ≈ 3.1±0.3,attributed to the movement of dislocation pile-ups on the basalplanes. The implications and importance of being able to carry outconstant stress experiments using a nanoindenter will be discussed.

9:00 AMSpherical Nanoindentation Stress-Strain Curves, KinkingNonlinear Elastic Solids and Low Dimensionality Solids (Invited)M. Barsoum*, Drexel University, USA

Recently we postulated that solids with high c/a ratios – that renderslip, other than basal, prohibitively expensive - belong to the sameclass we designated as kinking nonlinear elastic, KNE. The signatureof KNE solids is the formation of fully reversible, hysteretic, stress-strain loops, on repeat loadings. This full reversibility is due to the for-mation of incipient kink bands, that are comprised of two, nearly par-allel, dislocation walls of opposite polarity that are attracted to eachother; when the load is removed they annihilate. The energy dissi-pated per cycle is substantial and increases with increasing stress. Re-cently we have shown that repeated spherical nanoindentation, NI, re-sults - when converted to NI stress strain curves - on the same

location is a technique that is ideally suited to characterize KNEsolids, that tend to be layered and thus of lower dimensionality. Ex-amples on Ti3SiC2, mica, graphite, sapphire, LiNbO3, among othersare presented.

10:00 AMApproaching the Theoretical Strength of Silicon: Tensile Behaviorof Silicon NanowiresM. Steighner*, The Pennsylvania State University, USA; D. C. Miller,University of Colorado, USA; B. L. Boyce, Sandia National Laboratory, USA;C. L. Muhlstein, The Pennsylvania State University, USA

Nanoscale volumes of materials with very low, controlled defectdensities can be realized with a variety of nanowire fabricationstrategies. In this empirical study, the tensile deformation and fail-ure behavior of silicon nanowires manufactured using a vapor-liq-uid-solid (VLS) growth system were characterized with a micro-machined loadframe and actuator. The diameter and orientation ofthe silicon nanowires were first characterized in a transmissionelectron microscope (TEM). Subsequent testing was performed invacuum after manipulation in a scanning electron microscope(SEM) equipped with a Ga focused ion beam. A series of tensiletests revealed that the elastic moduli of the nanowires approachedthat of bulk silicon and the fracture strength approached the theo-retical value for the absolute strength of silicon. Images of the fail-ure surfaces were used to compare the nanoscale failure mecha-nism to the ideally brittle behavior that is characteristic of bulksilicon.

10:20 AMQuantitative Fracture Toughness Measurements of Thin FilmsD. Morris*, National Institute of Standards and Technology, USA

Quantitative fracture toughness measurements of thin films aremuch more difficult than the well-understood measurement of elas-tic and plastic properties. A very acute probe like a cube-corner mayused to create indentation flaws on the scale of the film thickness. Thestress field about a cube-corner indenter is very different from that ofa Berkovich indenter, such that the stresses are less Hertzian and morelike that of a surface-located wedge. Furthermore, even though cracksmay be contained in the film, film-substrate coupling is very strong,and is manifested in three distinct ways. After film-substrate couplingphenomena are identified, they may be combined with a model ofacute indentation to form a toughness measurement method that is,in principle, applicable to any brittle-film-on-substrate system. Ex-periment and theory will be demonstrated for nanoporous low-di-electric-constant (low-k) films on silicon substrates.

10:40 AMBulk Synthesis of Silica Nanowires and Self-assembledHierarchical StructuresZ. Liu*, J. C. Yang, University of Pittsburgh, USA

One-dimensional (1D) nanostructures have attractive properties andcan be integrated into various nanodevices. Thus, the synthesis of 1Dhas become the focus of intensive research. Hierarchical nanostruc-tures that have both the properties of nanoscale materials and pro-vide an attractive alternative for bottom-up fabrication. They can beprepared by growing nanoscale structures of materials with differentdimensions scales. In addition, the core and branch of a hierarchicalstructure can be composed of different chemical elements, makingthem suitable for assemble into a nanodevices with multiple func-tions. Bulk quantities of silica nanowires, braided helical silicananowires and hierarchical nanostructures on silicon wafers havebeen synthesized by direct annealing of the 10nm iron thin film on Siwafer. The resultant silica nanowires and heterostructures were char-acterized by SEM, TEM, and EDS spectra. The possible mechanism tocontrol the nanostructure formation is discussed.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 179

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania180

11:00 AMSynthesis and Characterization of MgO-Y2O3 nanocompositesynthesized using argon-shrouded plasma systemJ. Al-Sharab*, R. Sadangi, V. Shukla, B. Kear, Rutgers University, USA; J.Bentley, Oak Ridge National Laboratory, USA

Polycrystalline Y2O3 is receiving a significant attention due to its im-portance in infra-red applications. This material will be replacing theAl2O3–sapphire due to its excellent optical properties in the visible,near infrared and mid wave (3-5 micron) region. However, currentprocessing techniques which include heat treatments at high temper-atures result in larger grain size (~ 150 microns) which will have anegative impact on the hardness and erosion resistance. Our currentresearch concentrates on the far-from-equilibrium synthesis andnano scale characterization of new class of Y2O3-MgO nano com-posite with improved integrity of mechanical and optical properties.Moreover, optical and dielectric properties of this nanocompositewill be estimated from the low loss EELS spectra according to theKramers-Kronig formula.

Fundamentals & Characterization:Performance and Growth of Bulk and ThinFilm Materials - Role of Surface and InterfacePhenomena during Growth and Processing

Recent Advances in Growth of Thin Film MaterialsRoom: 306Session Chair: N. Singh, Northrop Grumman Corporation, ES

8:00 AMMorphology of Nanodots and Nanocubes of Detector Materials(Invited)S. McLaughlin, B. Wagner*, N. B. Singh, A. Berghmans, D. Kahler, D.Knuteson, M. Fitelson, M. Singh, M. House, N. Paraskevopoulos, NorthropGrumman Corporation, ES, USA

For several decades, attempts have been made to find high tempera-ture infrared detectors based on PbSe-type heavy metal selenides. Toachieve this goal, attempts have been made to grow high quality highresistivity materials. We have developed nanodots and arrays ofnanocubes on Silicon (Si) wafers with and without catalyst. We usedsilicon (111) substrates for the growth runs. Several growth experi-ments were carried out and growth conditions were varied to studythe nucleation and growth of dots. The morphologies of the nan-odots were very much dependent on the growth conditions. We ob-served that the morphology was nanocubes and nanodots on waferswith and without catalyst. Larger oriented PbSe dots grew at hightemperature substrate temperature.

8:40 AMThin Film Medical Sensors (Invited)R. J. Narayan*, University of North Carolina, USA

Membrane biofouling and inflammation play significant roles in in-stability of implantable biosensors. An ideal biosensor membranematerial must both exhibit limited protein adsorption and promotetissue-biosensor integration. Furthermore, biosensor membranesmust exhibit low thickness and high porosity values in order to allowthe biosensor to respond to analyte fluctuations. In this study, the useof pulsed laser deposition to prepare thin films on anodized alu-minum oxide membranes for biosensor applications is discussed. Thenanoporous membranes were examined using several techniques, in-cluding scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and plateletrich plasma testing. We anticipate that these novel materials couldfind use in bioartificial organs, kidney dialysis membranes, drug de-livery devices, and other devices facing biocompatibility issues thatlimit in vivo function.

9:20 AMLong-term ordered crystals and their multi-layered film analoguesS. L. Pyshkin*, Academy of Sciences, Moldova; J. M. Ballato, ClemsonUniversity, USA

The useful for application in optoelectronics results of the long-termordering of impurities and host atoms of the crystal lattice in dopedGallium phosphide, presented here and at the 2005-2008 TMS andMS&T conferences, give a new stimulus for growth on a crystallinesubstrate or an semi-fabricated microchip of the multi-layered devicestructure having a periodic 1-, 2-, 3-d disposition of impurities. Nowwe present elaborated by us combined methods of molecular beamand laser assisted epitaxies for growth of these structures, well-matched with a substrate on the type and the identity parameter ofany crystal lattice and having due to this fact the perfect interface andsurface. Thus, we develop the artificial analogue of naturally formedfor over 40 years the nitrogen impurity superlattice with the identityperiod of the order of the Bohr dimension of the N-bound exciton,and it means creation of a new crystal-like excitonic medium with anextremely low intensity threshold for non-linear optic phenomena.

10:00 AMSynthesis and characterization of bandgap reduced p-type Cuincorporated ZnO films (Invited)S. Shet*, K. Ahn, Y. Yan, J. Turner, M. Al-Jassim, National Renewable EnergyLaboratory, USA; N. M. Ravindra, New Jersey Institute of Technology, USA

Cu doped ZnO thin films with significantly reduced bandgaps weresynthesized by incorporation of Cu at room temperature and fol-lowed by post-deposition annealing at 500°C in air for 2 hours. All thefilms were synthesized by RF magnetron sputtering in O2 gas ambienton F-doped tin oxide-coated glass. We found that annealing at 600 oCcaused the formation of the CuO phase in the ZnO:Cu films, whereas500 oC films did not. Optical absorption indicated that some of theCu in as-grown ZnO:Cu films is metallic. It can be converted intoCu+1 acceptor states by postdeposition annealing at 500 oC in air.Mott-Scottky plots, open circuit response to illumination, and illumi-nated I-V curves along with optical-absorption measurements re-vealed that ZnO:Cu thin films with p-type conductivity and signifi-cantly reduced bandgap were successfully synthesized by Cuincorporation.

10:40 AMModeling and Simulation of Magnetic Field Assisted AssemblyG. Devrani*, R. D. Rivero, M. R. Booty, A. T. Fiory, N. M. Ravindra, NewJersey Institute of Technology, USA

A simple model to simulate the magnetic field distribution, usingVizimag, has been implemented. Solenoids of different shapes havebeen utilized to serve as electromagnets. Magnetic shielding tech-niques have been deployed to isolate the influence of one solenoidover the other. These solenoids are used to move the devices that needto be placed in recesses in the substrate. The devices are made from avariety of materials such as Gallium Arsenide (GaAs), Gallium Ni-tride (GaN) etc, to perform different functionalities. The devices andthe recesses are coated with magnetic materials to facilitate the move-ment and placement of devices within recesses.

11:00 AMEvolution of a 3D Grain within a Thin Film: Surface DiffusionEffects (Invited)A. Vilenkin, Hebrew University of Jerusalem, Israel; A. Novick-Cohen*,Technion-IIT, Israel

To understand the influence of surface diffusion on grain growth andthe stability of thin polycrystalline films, we study the evolution of asingle grain which is initially a circular cylinder embedded within athin film composed of a single crystal. A numerical code is used tofollow the 3D coupled motion by mean curvature of the grain bound-ary, and the motion by surface diffusion of the external surfaces. Our

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 180

Wed

nes

day

AM

www.matscitech.org 181

physical modeling is based on classical discussions of Mullins. Our re-sults indicate that, depending on the values of the geometric and ma-terial parameters, the grain can either annihilate, or grooving can re-sult in pinch off, and diagrams of the transition are presented. Thenumerics show that the delay of grain shrinkage due to grooving dif-fers from Mullins’s predictions, and that grain growth dynamics inthin film can be dramatically affected by surface grooving.

11:40 AMTEM Research on the Growth of Pt Clusters Deposited on γγ-Al2O3/NiAl(110)Z. Zhang*, L. Li, University of Pittsburgh, USA; S. I. Sanchez, University ofIllinois at Urbana-Champaign, USA; Q. Wang, Yeshiva University, USA; L.Wang, D. D. Johnson, University of Illinois at Urbana-Champaign, USA; A. I.Frenkel, Yeshiva University, USA; R. G. Nuzzo, University of Illinois atUrbana-Champaign, USA; J. C. Yang, University of Pittsburgh, USA

The structure of deposited Pt nanoclusters is related mostly to thesubstrate. A well oriented epitaxial oxide film will influence thegrowth of metal clusters because of its long-range order and uniformstructures. Many researches have demonstrated that the controlledoxide films will determine the growth of nanopartiles including size,uniformity or morphology. However, mechanism dominated innanopartiles growth is still unclear. In this presentation, we plan tosynthesis a well ordered epitaxial γ-Al2O3 film on the NiAl (110)alloy. The nanometer sized Pt particles are then deposited throughvapor deposition method onto the film. The surface characterizationsof Pt/γ-Al2O3 are investigated by X-ray diffraction, transmissionelectron microscopy and atomic force microscopy. The relation be-tween particle growth and substrate structure is discussed. Throughdifferent temperatures and deposition rates, the dominant growthmode of nanocluster has also been debated.

Fundamentals & Characterization: PhaseStability, Diffusion Kinetics and TheirApplications (PSDK-III)

Diffusion Kinetics IIIRoom: 302Session Chairs: Nagraj Kulkarni, Oak Ridge National Laboratory;Liang Jiang, GE Central Research & Development

8:00 AMDiffusion Path Development in Single-phase Cu-Ni-ZnMultilayered Assemblies (Invited)M. A. Dayananda*, Purdue University, USA

Selected multilayered diffusion assemblies (MDAs) investigated at775oC with α(fcc) Cu-Ni-Zn alloys are presented in this study. Singlephase, multilayered diffusion assemblies (MDAs) sandwiching anynumber of finite layers of multicomponent alloys between two bulkterminal alloys are analyzed for temporal and spacial evolution ofconcentration profiles and diffusion paths. The analysis is based on atransfer matrix method utilizing a set of constant interdiffusion coef-ficients applicable to all alloys in the MDA. Concentration profilesand diffusion paths are simulated for MDAs with only one finite alloymiddle layer between the terminal alloys. The simulated diffusionpaths evolve with time initially from two S-shaped segments to an S-shaped path corresponding to the solid-solid couple assembled withjust the terminal alloys. The evolution of the diffusion paths is dis-cussed in the light of the middle alloy layer thickness and the devel-opment of zero-flux planes in the diffusion zone.

8:40 AMCarbon diffusion in pure iron under a magnetic fieldH. Fujii*, Tohoku University, Japan; S. Tsurekawa, Kumamoto University, Japan

This study was conducted at the aim of investigating the effect of amagnetic field on the carbon diffusion and its solubility in pure iron.

An Fe/Fe-0.87mass%C diffusion couple explosively welded was an-nealed at temperatures between below the Curie temperature(1043K) of iron and above the α-γ transformation temperature(1184K) without and with a magnetic field up to 6T. We evaluated thecarbon diffusivity in iron from the penetration profiles of carbon iniron measured by secondary ionization mass spectroscopy (SIMS).The diffusivity of carbon in both α- and γ-iron was decreased in amagnetic field. A decrease in the diffusivity was more significant inα-iron than in γ-iron. The diffusivity in α-iron at 1000K exponen-tially decreased with increasing a magnetic field strength. The activa-tion energy for carbon diffusion in α-iron was not different irrespec-tive of whether a magnetic field was applied. The solid solubility ofcarbon in α-iron increased by approximately twice under a 6T mag-netic field.

9:00 AMMicrostructural Simulation and Life Prediction for Advanced GasTurbine Coatings (Invited)L. Jiang*, J. Zhang, G. Singh, GE Global Research, USA; C. Hardwicke, GEEnergy, USA

In the severe operation environment of gas turbines, advanced metal-lic coatings are used as environmental coatings or as bond coats be-tween superalloy substrate and ceramic thermal barrier coating forprotecting substrate superalloy from oxidation and hot corrosion.Both oxidation and interdiffusion between the metallic coatings andsubstrate alloys result in progressive degradation of the metallic coat-ing. Coupled with thermodynamic and kinetic databases, a simplifiedmodel with consideration of multicomponent diffusion in singlephase was developed for the calculation of interdiffusion profiles andlifing of metallic coatings. A more sophisticated model with consider-ation of multicomponent diffusion in multiphase was developed forthe microstructural evolution in coatings. The models help under-stand the failure mechanisms of metallic coatings for gas turbinesand can capture the detrimental effects resulting from oxidation andinterdiffusion.

10:00 AMInstrument Error and its Propagation through DiffusionCoefficient Measurement Procedures (Invited)J. C. LaCombe*, A. V. Jaques, University of Nevada, Reno, USA

In current practice, there is typically no quantitative connection be-tween instrument uncertainties (resolution, etc.) and the analytically-derived [D] values. In lieu of these, we typically identify only qualita-tive uncertainties when reporting diffusivity data. To measure howerrors propagate through the analysis of concentration data and in-fluence [D], we performed a series of Monte Carlo simulations (nu-merically-generated concentration profiles), to learn how instrumentspot size and positioning uncertainties affected the derived [D] val-ues. We identified several useful scaling relationships. For example,errors in the diagonal terms, δDii scale parabolically with the instru-ment spot size, and inversely to the diffusion time. Such relationshipsallow researchers to make more rigorous and quantitative estimatesof the errors in their measured data, and are valuable in experimentdesign to achieve a desired level of precision for a given experiment.

10:40 AMDetermining Diffusivities and Solid Solubilities of Yb and Er in Alby Microstructural Characterization of Aged Al-Yb and Al-Er AlloysM. E. van Dalen, R. A. Karnesky, D. Dunand, D. N. Seidman*, northwesternuniversity, USA

Aluminum alloyed with 0.03-0.06 at.% RE (RE=Yb or Er) was agedto produce nanosize Al3RE precipitates (L12 structure). The evolu-tion with aging time at 300°C of the mean precipitate radii and ma-trix supersaturation, as measured by transmission electron mi-croscopy and Local-Electrode Atom-Probe (LEAP) respectively, are

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 181

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania182

consistent with the Lifshitz-Slyozov-Wagner model. The rate con-stants for these processes are used to determine, for each RE, the dif-fusivity in and the Al/Al3RE interfacial free energies at 300°C. REmaximum solid solubilities in Al are also measured near the eutectictemperature. As compared to Sc, RE exhibit higher diffusivity andAl/Al3RE interfacial energy, but lower solubility in Al. This research issupported by the United States Department of Energy through grantDE-FG02-98ER45721.

11:00 AMInterdiffusion Behavior and Microstructural Development of U-7wt.%Mo, U-10wt.%Mo and U-12wt.%Mo Alloys in Contact withAl and 6061Al alloy at 600°°CE. Perez*, University of Central Florida, USA; D. Keiser, Idaho NationalLaboratory, USA; Y. Sohn, University of Central Florida, USA

U-Mo dispersion fuels in Al-base alloys are being developed to fulfillthe requirements to use low enriched uranium in research reactors. Inthis study, interdiffusion behavior of U-Mo-Al system was examinedwith solid-to-solid diffusion couples of U-7wt.%Mo, U-10wt.%Moand U-12wt.%Mo vs. Al and 6061Al, which were annealed at 600°Cfor 24 hours. Scanning electron microscopy revealed the developmentof a complex interdiffusion microstructure that consisted mostly ofvery fine mixture of various aluminides. Electron probe microanaly-sis was carried out to determine the profile of average compositionacross the reaction diffusion layer. X-ray diffraction and transmissionelectron microscopy were employed to determine the exact identityof the phase constituents within the reaction diffusion zone.

11:20 AMEnhanced Carbon Diffusion in Austenitic Stainless SteelCarburized at Low TemperatureF. Ernst*, A. Avishai, H. Kahn, X. Gu, G. M. Michal, A. H. Heuer, CaseWestern Reserve University, USA

Austenitic stainless steel AISI 316L was carburized by a novel, low-temperature gas-phase process. Using calibrated scanning Auger mi-croprobe analysis of cross-sectional specimens under dynamic sput-tering, we determined the concentration–depth profile of carbon.The profile is concave – very different from the error-function-likeshape expected for concentration-independent diffusion – and indi-cates carbon fractions up to 0.15 in solid solution and a case depth ≈30 μm. Boltzmann–Matano analysis with careful evaluation of errorsindicates that increasing levels of carbon significantly enhance car-bon diffusion. For the highest carbon fraction observed (0.15), thecarbon diffusion coefficient is more than two orders of magnitudelarger than in dilute solution. The most likely explanation for thisstrong increase is that carbon-induced local expansion ofmetal–metal atom distances, manifesting itself as an expansion of thelattice parameter, reduces the activation energy for carbon diffusion.

11:40 AMExploiting anomalous diffusion near polymorphic transition toachieve deep titanium boride surface coatings on titaniumB. Sarma*, N. Tikekar, K. Chandran, University of Utah, USA

The nature of growth of titanium boride (TiB) whisker coatings onCP-titanium surfaces at temperatures near the alpha-beta polymor-phic transition temperature is examined. It is known that HCP metalslike Ti show enhanced anomalous self-diffusion near the phase tran-sition temperature within a range of about 100 degrees above thetransition temperature. We explore the nature of boron diffusion inthis anomalous region and the consequent growth kinetics of hardTiB layers. Boron was diffused into titanium for various periods oftime near the alpha-beta polymorphic transition temperature. It wasfound that there is a deeper TiB penetration in the substrate as thetransition temperature is approached. Indentation hardness meas-urements show the nature of change in hardness in coated surfacefrom the edge of the substrate to the interior. The results are analyzed

in terms of anomalous diffusion and phase accommodation near thepolymorphic transition.

Fundamentals & Characterization: PhaseTransformations and MicrostructuralChanges during Sustained MechanicalForcing

Deformation-induced Microstructural Changes andPhase Transformations IIRoom: 310Session Chair: Rainer Hebert, University of Connecticut

8:00 AMDissolution of cementite in carbon steels by severe plasticdeformation (Invited)M. Umemoto*, Y. Todaka, Toyohashi University of Technology, Japan

The dissolution behavior of cementite by heavy deformation in eu-tectoid steels with pearlitic and spheroidite structures was studied. Toexamine the thermal effect on the cementite dissolution, pulsed laserheating was also carried out. By ball drop deformation, the cementitedissolved and the matrix became nano-grained. After pulsed laserheating, re-austenitized region transformed to fresh martensite dur-ing quenching. The boundary between the re-austenitized region andmatrix exhibited similar microstructure with that observed in speci-mens subjected to ball drop deformation. It was suggested that thedissolution of cementite by heavy deformation at high strain ratewere probably due to thermal effect, that is, re-austenitization.

8:40 AMConfirmation of a Pressure-Induced Phase Transformation in ββ-Eucryptite with In-Situ Raman SpectroscopyT. Jochum*, I. Reimanis, Colorado School of Mines, USA; M. Lance, OakRidge National Laboratory, USA

β-Eucryptite (LiAlSiO4) is used as a constituent in composites with anear zero coefficient of thermal expansion. It exhibits an unusual phe-nomenon when exposed to a sufficient compressive stress, such as thatexperienced underneath an indenter; particles of the material areejected from the stressed location in a sustained stream. The source ofthis phenomenon has been previously explained by the release of veryhigh stored elastic energy or the existence of a reversible pressure-in-duced phase transformation, or some combination of the two. In-situRaman analysis during indentation revealed the growth of a new peak,likely a second phase, under increasing load. The peak subsequentlydisappears during unloading. The relation of these experiments to theobserved pressure-induced particle ejecta phenomenon is discussed.

9:00 AMThe effect of strain on the microstructural evolution in metalcutting chips in AA 2195 T81L. Dong*, J. Schneider, Mississippi State University, USA

Metal cutting experiments were conducted on AA 2195 T81 to evalu-ate the effect of strain on the resulting microstructure. Differentstrains were imposed on the chips by varying the cutting parameters.The morphology and phase content of the microstructure was docu-mented using optical microscopy, electron microscopy and x-ray dif-fraction. The results show that the machine chips were composed ofultra-fine grains with variations observed at increasing levels of strain.

9:20 AMLayer refinement of Mo-Ta multilayers during accumulative rollbondingR. Hebert, G. Marathe*, University of Connecticut, USA

Bulk Mo-Ta multilayers can be synthesized with layer thicknessesof less than 500 nm from commercial Mo and Ta foils based on ac-

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 182

Wed

nes

day

AM

www.matscitech.org 183

cumulative roll bonding (ARB). The ARB technique involves a re-peated rolling and folding process of arrays of elemental layers.Nanoindentation measurements of Mo-Ta, Mo-Mo, and Mo-Tamultilayers as well as tensile testing experiments provide inputdata for continuum mechanics modeling of plastic instability oftrilayers during cold rolling. The continuum mechanics model al-lows for a prediction of the onset of diffuse necking. Model predic-tions are compared with the analysis of cross-sectional microscopyimages. The results of the nanoindentation measurements indicatethat effects such as dynamic recovery should be taken into ac-count. The combination of mechanical measurements and contin-uum mechanics models offer a novel approach to gauge the mi-crostructure evolution of multilayers under sustained deformationconditions.

10:00 AMDegradation of Three Ni-based Superalloys Used for Gas TurbineHot-Gas Path Components after Long Term AgingsD. Saito*, TOSHIBA Corporation, Japan

In case of enhancing operation temperature of land base gas turbines,it is very important to understand the materials degradation mecha-nisms of hot-gas path components. In this study, long term agings atthe high temperature were conducted for three kinds of Ni-based su-peralloys, Hastelloy X, Nimonic 263 and IN738LC. Through the mi-crostructure observations and the identifications of the precipitatesin these three alloys aged at various conditions, new Time-Tempera-ture -Precipitation diagrams were determined for the alloys. Thequantitative analyses of intragranular precipitates, such as volumefraction, size and inter-particle spacing of precipitates, were con-ducted. The degradation behaviours of these alloys aged were evalu-ated by the creep tests at relatively higher stress conditions. The ratioof the minimum creep rate to that of the initial as-heat-treated onewas used as an indication of degradation and the ratio is called adegradation ratio in this study.

Fundamentals & Characterization: RecentAdvances in Structural Characterization ofMaterials

New Techniques and Multidimensional ApproachesRoom: 309Session Chairs: Roumiana Petrova, New Jersey Institute ofTechnology; Jacob Jones, University of Florida

8:00 AMEmergent Phenomena at Epitaxial Interfaces: A Structural View(Invited)R. Clarke*, University of Michigan, USA; P. Willmott, S. Pauli, C. Schlepuetz,Paul Scherrer Institut, Switzerland; Y. Yacoby, Hebrew University, Israel; D.Kumah, N. Husseini, University of Michigan, USA

We have applied a direct x-ray phasing method, Coherent Bragg RodAnalysis (COBRA), to epitaxial oxides such as LaAlO3 - SrTiO3, ofinterest because it is known to form a quasi-2D electron gas at the in-terface between two nominally insulating materials. This class of per-ovskite oxides is interesting because it exhibits various important“emergent” correlated electron phenomena such as novel metal insu-lator transitions, interface superconductivity and ‘colossal’ magne-toresistance. The COBRA measurements reveal the formation of ametallic La,SrTiO3 layer with an accumulation of trivalent Ti at theinterface which is responsible for the lattice dilation, minimizing theelectrostatic energy at the TiO2-terminated SrTiO3 substrate surfaceand lowering the conduction band minimum below the Fermi level.These findings establishes a structural basis for the conducting inter-face as well as suggesting interesting directions for the design of epi-taxial oxide multilayers with novel dielectric properties.

8:20 AMRaman Spectroscopy and Electron Diffraction of FunctionalCeramics (Invited)I. M. Reaney*, University of Sheffield, United Kingdom

To understand and interpret the functional properties of a ceramic,knowledge of the macroscopic crystal structure is often insufficient,since many properties are controlled by local correlations on thenanoscale. Obtaining information concerning such short range inter-actions is difficult, particularly utilising laboratory based equipment.Of the equipment typically available to most researchers, the combi-nation of transmission electron microscopy and Raman spectroscopyoffers the greatest promise. This presentation highlights new dataconcerning classic functional oxides such as barium titanate and leadzirconnate titanate which have been obtained using electron diffrac-tion and Raman spectroscopy.

8:40 AMStructure-Property Relationships in Ferroic Nanostructures(Invited)A. Petford-Long*, A. Chiaramonti, M. Tanase, D. Schreiber, Argonne NationalLaboratory, USA

We are using in-situ TEM, probe force microscopy and atom probetomography (APT) to study nanostructures including exchange-bi-ased bilayers and magnetic tunnel junctions (MTJs). These materialsshow novel properties engineered by controlling the microstructurein nm-scale layers and by lateral confinement. For example, LorentzTEM and micromagnetic modeling have allowed us to quantify theexchange bias (EB) in disks for which EB has been set in a vortex. Weare using in-situ TEM to measure local transport across the nanoscaleoxide barrier in MTJs whist imaging the nanostructure of the barrierat the exact same position. Combining APT and in-situ TEM trans-port data enabled us to show that oxidation of the ferromagnet at oneof the barrier interfaces leads to an asymmetry in the tunneling be-havior that is reduced following annealing. This manuscript has beencreated by UChicago Argonne, LLC, Operator of Argonne NationalLaboratory, a U.S. DOE Office of Science Laboratory operated underContract No. DE-AC02-06CH11357.

9:00 AMCharacterization of Defect-Structure in Acceptor- and Donor-modified Piezoelectrics by Multifrequency and Multipulse EPRSpectroscopy (Invited)R. Eichel*, Technische Universität Darmstadt, Germany

Multifrequency and Multipulse Electron Paramagnetic Resonance(EPR) spectroscopy is used to characterize the structure and dynam-ics of aliovalent iron, copper, manganese and gadolinium functionalcenters in piezoelectric ceramics. In particular, mechanisms of chargecompensation through the formation of oxygen vacancies are enlight-ened. More generally, the oxygen vacancies form defect dipoles withthe acceptor dopants. Furhtermore, models are developed that explainmacroscopic material properties, such as the hardening and softeningeffect, as well as dynamic mechanisms such as ferroelectric aging.

9:20 AMSpectroscopic Imaging of Defect-Controlled PolarizationDynamics on a Single Defect Level (Invited)S. V. Kalinin*, S. Jesse, A. Baddorf, Oak Ridge National Laboratory, USA; E. A.Eliseev, A. N. Morozovska, National Academy of Sciences of Ukraine,Ukraine; S. Choudhury, L. Chen, Pennsylvania State University, USA

Polarization switching in ferroelectric materials is controlled bystructural defects that act both as the local nucleation centers and thepinning centers for moving domain walls. Progress in nanoscale fer-roelectric device applications ranging from FeRAM to data storage totunneling barriers necessitates understanding of polarization switch-ing mechanism on a single structural or morphological defect level.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 183

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania184

Here, we report the experimental results of spatially resolved spectro-scopic imaging studies of defect controlled nucleation in ferro-electrics using combination of piezoresponse force spectroscopy, ana-lytical theory, and phase field modeling. Using the probes withcalibrated geometry, we demonstrate that the nucleation bias inPiezoresponse Force Microscopy experiment on a nearly-ideal sur-face is within factor of 2 from thermodynamic limit. Spatially re-solved mapping of local nucleation biases allows nucleation centers tobe visualized, and corresponding thermodynamic and kinetic param-eters to be reconstructed.

10:00 AMNucleation and Growth Dynamics of Individual FerroelectricDomains with High Speed Scanning Property Mapping (Invited)N. Polomoff, R. Nath, J. Bosse, A. Lucas, B. D. Huey*, University ofConnecticut, USA

Scanning Probe Microscopy provides superb resolution for mappingsurface properties, but is generally limited to static studies due to arelatively slow scanning speed (typically 4 minutes per frame orlonger). Based on a recent development, novel high speed surfaceproperty mapping is now possible allowing full frame, full resolutionimages in one second or less (>256 Hz line rates). Accordingly, the dy-namics of ferroelectric domain switching, hysteresis, and relaxationcan be directly imaged. This reveals the spatial distribution of nucle-ation sites as a function of microstructural defects, interfaces, filmthickness, composition, etc. The distributions of domain switchingactivation energies and times are also mapped.

10:20 AMPhoto-stimulated luminescence spectroscopy and high energy x-rays to advance stress measurements in polycrystalline ceramicsS. Raghavan*, P. K. Imbrie, Purdue University, USA

The photo-stimulated luminescence spectroscopy (PSLS) techniqueprovides the means to establish stress dependencies of the well-known spectral peak positions (R-lines) in polycrystalline alumina.Presented here, are the results of compression tests performed to de-termine the coefficients describing this piezo-spectroscopic (PS) be-havior. In addition to the R-line spectral peak-shifts, the less exploredvibronic band peaks in the emission spectrum are introduced and thePS coefficients of several peaks within these bands are determinedwith respect to their shifts with stress. Synchrotron x-ray experimentswere also conducted as an independent stress measurement methodupon which these optical fluorescence shifts can be calibrated,thereby advancing the accuracy of PS coefficient determination. Theresults set the foundation for the exploitation of vibronic band peak-shifts for the measurement of the complete stress state in polycrys-talline alumina.

10:40 AMDirect three-dimensional microstructural characterization ofTi-5111V. Dixit*, P. Collins, H. L. Fraser, The Ohio State University, USA

Several developments have made possible the direct 3D characteriza-tion of microstructures across length-scales. These techniques, in-cluding the Robo.Met-3D™, the Dual-Beam (SEM/FIB), and (S)TEMtomography have been used to characterize the microstructure of Ti-5111 (Ti-5Al-1V-1Zr-1Sn-0.8Mo). In general, the microstructure oftitanium alloys can be quite complex, with features of interest span-ning a broad range of length scales. Significant variations in the sizeand morphology of the microstructural features have been producedas a function of different thermomechanical histories. Subsequently,the overall morphological details of the microstructure have beencharacterized using the three techniques described above. Addition-ally, the DualBeamTM FIB/SEM was used to acquire serial EBSDmaps to provide further information to relate crystal orientation withthe microstructural features. It will be shown that such 3D informa-

tion can be used to populate databases containing structure andproperties.

11:00 AMAdvanced Microstructural Characterization of FirnI. Baker*, S. Chen, R. Lomonaco, Dartmouth College, USA; R. Obbard,British Antarctic Survey, United Kingdom; D. Iliescu, Seldon Technologies,Inc., USA; N. Spaulding, D. Meese, University of Maine, USA

Traditionally snow firn has been characterized by infiltrating thepores with a liquid, such as dimethyl phthalate; allowing the infiltrateto set; sublimating the ice; and then sectioning and examining the in-filtrate optically. Problems with this technique are that the infiltratecannot penetrate small or closed-off pores and the possibility of theinfiltrate altering the structure. In this talk, the use of both micro CTand a scanning electron microscopy to determine porosity and thesurface area/unit volume of pores will be outlined. Grain boundarygrooves are used to distinguish where previously-existing snow crys-tals are joined, and to determine the grain size. The use of X-ray spec-troscopy and electron back-scattered diffraction patterns to deter-mine, respectively, the microchemistry of impurities in the firn andthe orientations of the firn crystals will also be presented. Supportedby ARO grant DAAD 19-03-1-0110 and NSF grants 0440523 and0538494.

11:20 AMAdaptive Diffraction Phenomenon and MicrostructuralCharacterization of Nanodomained MaterialsY. U. Wang*, W. Rao, Virginia Tech, USA

A nanodomain diffraction theory is developed. It reveals drasticallydifferent diffraction phenomenon in nanodomained materials fromthat in coarse-domained materials. Since nanodomain sizes are sig-nificantly smaller than the coherence length of diffraction radiation,the scattered waves from individual nanodomains interfere with eachother, leading to an adaptive diffraction phenomenon peculiar tonanotwinned materials, where conventional peaks disappear whilenew peaks appear at positions determined by a lever rule according totwin variant volume fractions. Brillouin zone-dependent criterion fortransition between adaptive diffraction and conventional diffractionis derived. The adaptive diffraction peaks exhibit anisotropic broad-ening and diffuse reflection feature with Lorentzian shape character-istics. Quantitative information of nanotwin microstructures can beobtained from the adaptive peaks. Relevant experimental observa-tions are also presented.

Fundamentals & Characterization: The Effectof Electrical (and Electromagnetic) Fields andStress (and Capillarity) on DiffusionalTransport in Ceramics and RelatedPhenomena

Interface KineticsRoom: 311Session Chair: Rishi Raj, University of Colorado

8:00 AMInfluence of an Electric Field an Equilibria And Kinetics inCeramics (Invited)H. Conrad*, North Carolina State University, USA

Hans Conrad Material Science and Engineering Department NorthCarolina State University Raleigh, NC 27695-7907 Abstract The in-fluence of an electric field E on solid state equilibria and kinetics inceramics is presented. Included are: (a) the effect of E on phase equi-libria in glasses, (b) the effect on dynamic grain growth in oxides and(c) the effect on plastic deformation kinetics in oxides. Important inphase equilibria is the difference in dielectric constant between the

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 184

Wed

nes

day

AM

www.matscitech.org 185

matrix and the precipitate. Regarding dynamic grain growth, the in-fluence of E is mainly on the pre-exponential, presumably on thedriving force. In plastic deformation kinetics it is proposed that theinfluence of E is through its reduction of the electrochemical poten-tial for the formation of vacancies pertaining to the diffusion of therate controlling ion. Research relating to the topic of paper was sup-ported by the Army Research Office and by the Oak Ridge NationalLaboratory.

8:40 AMInfluence of Electrical Fields on Grain Growth in CeramicsS. Ghosh, A. H. Chokshi, Indian Institute of Science, India; R. Raj*, Universityof Colorado at Boulder, USA

There is growing experimental evidence for a coupling between elec-trical fields and phenomena in ceramics, such as diffusional creep andsintering, which heretofore, have been assumed to be driven by me-chanical and capillary forces. Electrical fields have been shown to re-duce the flow stress for creep in zirconia and alumina (Conrad, H, etal.), and conversely, the application of normal stress has been shownto produce an electrical potential at temperatures where interfacialdiffusion is viable (Pannikkat et al.). A theoretical model on the influ-ence of interfacial space charge on self–diffusion has been developed(Jamnik et al.). Experiments that are likely to show a significant influ-ence of electrical fields on sintering behavior are pending. In thispaper we show that the application of electrical fields can signifi-cantly retard the rate of grain growth in zirconia.

9:00 AMElectrical field enhances the grain growth in MgAl2O4 spinelB. Franck*, C. Jacques, N. Nicolas, B. Alain, University of Lille1, France

The work is presented here consists of the study of the kinetics ofgrain growth under electric field. We have annealed in air a near stoi-chiometric spinel with and without an applied electrical field. Itclearly shows that the kinetic of the grain growth always follows a t1/2law and that the electrical field enhances the grain growth rate. Weshowed in previous works the presence of a space charge near theGrain Boundary (GB). The analyse of those results have been carriedout according to Chiang and Kingery’s study on the rate of graingrowth in spinel versus stoichiometry; and with Jeong et al who stud-ied the acceleration of migration of a GB under an electric field. Weconclude that the point defect mobility across the GB is controlled bythe space charge and that the applied electrical field creates an addi-tional driving force on well oriented GB. A GB curvature analysiscombined with this effect explain that the acceleration of graingrowth retain the equiaxis shape of grains

Li+ BatteriesRoom: 311Session Chair: Rishi Raj, University of Colorado

10:00 AMLithium metal oxide electrodes with structurally integrated Li2MnO3 for advanced lithium-ion batteries (Invited)S. Kang*, M. M. Thackeray, Argonne National Laboratory, USA

Recent, newly-emerging applications of lithium-ion batteries, e.g.,(plug-in) hybrid electric vehicles, have created significant researchneeds to develop advanced electrode materials with lower cost, im-proved energy density, and enhanced thermal safety than lithiumcobalt oxide that is currently used in commercial lithium-ion batter-ies. At Argonne National Laboratory, we have adopted unique materi-als-design strategies to develop advanced, high-capacity cathode ma-terials by using a Li2MnO3 component as a structure-stabilizing unitin layered compounds. By integrating the structurally compatibleLi2MnO3 in layered LiMO2 matrix (M=Ni,Co,Mn), we could success-fully improve cycling stability as well as achieve very high capacity ex-ceeding 200 mAh/g. In this paper, a detailed account of the structural,

chemical, and electrochemical features of lithium metal oxide elec-trodes containing a structurally integrated Li2MnO3 component forlithium-ion batteries will be discussed.

10:40 AMAnalysis of Surface Interfaces and Interphases (Invited)A. Dillon*, S. Asher, C. Perkins, D. Gillaspie, E. Whitney, National RenewableEnergy Laboratory, USA; S. Lee, University of Colorado, USA

It is well known that irreversible changes and reactions occur at theinterface between the active electrodes and electrolyte when a Li-ionbattery is cycled. This is of direct interest because irreversible reac-tions occurring on electrodes have been implicated in poor cell life-times. We recently discovered that anodes fabricated exclusively fromcrystalline MoO3 nanoparticles have an unprecedented reversible ca-pacity of 630 mAh/g and durable high rate capability. However, in theMoO3 nanoparticles not all of the Li is removed reversibly after thefirst electrochemical cycle. This may be attributed to irreversible in-sertion or an irreversible reaction at the surface. X-ray photoemissionspectroscopy will be employed to study the MoO3 nanoparticles fol-lowing the first electrochemical cycle (without exposure to air) togain precise understanding of the irreversible process.

11:20 AMPolymer derived ceramics for lithium-ion batteries (Invited)D. Ahn, S. Lee*, R. Raj, University of Colorado, USA

In the past decade, considerable effort has been devoted toward de-veloping new electrode materials for Li-ion batteries. Improvementin energy density and rate capability coupled with a simultaneous re-duction in cost and material toxicity remain the subject of intensiveresearch. Here we report the synthesis and electrochemical perform-ance of a novel polymer derived ceramic (PDC) material for Li-ionbattery applications. PDC nanodomain materials have been synthe-sized directly from polymers using liquid organic precursors. Theyare chemically inert and highly stable. Most importantly, the PDCsare processed to generate a nanodomain structure containing com-plexes of Si-C-O, that form nanodomains (1-5 nm). Anodes fabri-cated from PDC nanodomain materials display both a high reversiblecapacity of 680 mAh/g and high-rate capability. These materials willimpact the next generations of rechargeable lithium-ion batteries, notonly for applications in consumer electronics, but especially for use inhybrid electric vehicles.

Iron & Steel: Steel Product Metallurgy andApplications

Material Testing and CharacterizationRoom: 330Session Chair: Lifeng Zhang, Missouri University of Science andTechnology

8:00 AMDeformation and Fracture of TRIP 700 Steel by Digital ImageCorrelationV. Savic*, L. G. Hector, P. D. Zavattieri, General Motors, USA; W. Tong,Southern Methodist University, USA

Transformation induced plasticity (TRIP) steels exhibit enhancedductility and high strength due to an austenite to martensite phasetransition that depends upon strain and temperature. Here, we pres-ent quasi-static tensile test results on TRIP 700 using a miniature ten-sile stage with a custom data acquisition system. Using a digital imagecorrelation method, two-dimensional strain fields were computedfrom a series of digital images acquired during each test. A high speedcamera with custom image acquisition algorithms was used to collectthe images. Mechanical properties were determined for coupons cutparallel with and transverse to the rolling direction. True stress-truestrain curves up to localized necking were extracted from the strain

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 185

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania186

contour maps. The Young’s modulus was determined via separateloading-unloading tests. Fracture surfaces were examined using scan-ning electron microscopy and energy dispersive spectroscopy in orderto infer the mechanism of tensile failure.

8:20 AMPropagating Deformation Bands in TWIP Steel from DigitalImage CorrelationP. D. Zavattieri*, L. G. Hector, General Motors Research and Development,USA; J. R. Fekete, General Motors, USA

Twinning induced plasticity (TWIP) steels are high Mn steels that ex-hibit extreme strain hardening and elongation. Tensile flow curves ex-hibit serrations due to dynamic strain aging associated with solute-dislocation interactions. Highly inhomogeneous plastic flow ismanifested by Portevin-LeChatelier (PLC) band propagation. In thisresearch, TWIP steel tensile coupons were quasi-statically deformedto fracture at room temperature. Images of one coupon surface wererecorded with a variable framing rate high speed digital camera andcustom image acquisition software. A digital image correlation tech-nique was used to compute incremental strain maps that quantifylocal strains and strain rates within the PLC bands. Band nucleationand the direction of band propagation were investigated in the vicin-ity of individual serrations. The impact of tensile coupon geometryon band propagation was also explored. Fracture surfaces and chem-istry were examined with SEM and energy dispersive maps.

8:40 AMComputer Modeling of Induction Heating Processes to EnsureSuperior Coil DesignsV. Rudnev*, Inductoheat, Inc., USA

Computer modelling of induction heating to show pros and cons ofpopular numerical modelling techniques including finite differencemethod (FDM), finite element analysis (FEA), mutual impedancemethod (MIM), boundary element method (BEM) are evaluated.Nonlinearity of material properties, including thermal conductivity,emissivity, specific heat, electrical resistivity and magnetic permeabil-ity, as well as convection and radiation thermal surface losses aretaken into consideration. Analysis of how different factors may im-pact transitional and final heating conditions of metal and what mustbe accomplished in the system design to maximize its effectivenessand guarantee the desired final thermal conditions. Case studies: -Multi-frequency in-line multi-coil induction heating of billets, rods,bars. - Induction surface hardening & tempering of complex-shapeparts (i.e, crankshafts, camshafts, gears).

9:00 AMDeformation and Hardening Characteristics of Low Carbon Steelat Elevated TemperatureK. Maciejewski*, O. Gregory, H. Ghonem, University of Rhode Island, USA

The microstructure and deformation properties of structural steelhave been characterized as a function of temperature and exposuretime. The amounts and morphology of carbides present were moni-tored using optical and SEM observations. It has shown that as thetemperature approaches the ferrite-austenite phase transformation,considerable diffusion of cementite plates and abnormal graingrowth occurs. Variations in hardening parameters have been exam-ined as a function of thermal exposure, by using a viscoplastic consti-tutive model to simulate the flow behavior. Monotonic and cyclictests were carried out to determine the hardening parameters re-quired for full identification of the model variables. The integratedmodel was then used to simulate the stress-strain behavior for vari-ous strain rate and temperature conditions. These equations were en-tered into a finite element procedure to simulate the progressive de-formation of a steel structure subjected to various thermal exposureconditions.

9:40 AMUsing NDT Image Processing Analysis to Study the Soundness andCleanliness of Accelerated Cooled Continuously Cast Steel SlabsM. R. Allazadeh*, C. Garcia, K. J. Alderson, A. J. DeArdo, University ofPittsburgh, USA

The continuously increasing demand for high quality cast steel slabsrequires faster casting and cooling speeds without sacrificing overallquality. Factors such as operating techniques and slab width have astrong effect on casting rate and increased productivity. One area thathas received limited attention is the accelerated cooling of slabs. Amajor objective of this work was to assess the soundness of continu-ously cast slabs that were accelerated cooled prior to completion ofthe γ to α transformation. To achieve this objective, a non-destructivetesting technique (NDT) was used to assess the level of anomalies ordefects found in the slabs. The results from the NDT analysis were as-sessed with the aid of software developed to identify the type of de-fects and their location in the slabs. These results were complementedwith a systematic microstructural analysis. This paper will presentand discuss the results of this NDT Image Processing Analysis

10:00 AMEffect of Substrate Hardness on Performance of An AlternativeStamping Die MaterialO. N. Cora*, M. Koc, Virginia Commonwealth University, USA

Newer die materials,surface enhancement techniques are needed tocircumvent the excessive friction and wear conditions emerging withthe use of alternative sheet material grades in automotive, aerospaceand appliance industries.AISI D2 is a commonly used die material incold forming industry thus far; however, because of its low galling re-sistance, it is being replaced by several other die materials such asDC53.It has higher hardness and toughness after heat treatment andincludes smaller primary carbides in its microstructure, which reducethe risk of chipping and cracking,with compare to D2.This studyaims to investigate the effect of substrate hardness on die wear resist-ance of DC 53 against several AHSS grades by utilizing the recentlydeveloped die wear test method.Die samples with different initialhardness values are coated with the thermal diffusion technique.Theassessment of wear is based on mass loss, surface roughness measure-ments, and commonly used wear parameters.

10:20 AMSpecimen Configurations for Gleeble DilatometryC. Samuel, S. Viswanathan*, The University of Alabama, USA

This study involved the design of specimens for Gleeble dilatometry ofirons and steels. In the Gleeble, specimens are rapidly heated by directresistance heating; copper grips and water cooled jaws are used to pro-vide electrical contact and heat transfer, especially for cooling. Dila-tion is measured across the sample diameter at the center of the sam-ple. Due to the use of cold grips, there is usually a steep temperaturegradient from sample center to the edge. In this work, a number ofspecimen geometries were investigated. Thermal profiles for the vari-ous specimen designs were measured, and the scatter in AC3 measure-ments for mild carbon steel were determined. Also, a finite elementmodel was used to simulate the thermal behavior of Gleeble speci-mens. The results indicate a considerable reduction in the thermalgradient (1C/mm) and corresponding scatter in measurements fornotched specimens in comparison to straight specimens (15C/mm).

10:40 AMInstrumented hole expansion testingA. Karelova*, E. Werner, Technische Universitaet Muenchen, Germany; A.Pichler, voestalpine Stahl Linz GmbH, Austria; C. Krempaszky, TechnischeUniversitaet Muenchen, Germany; T. Hebesberger, voestalpine Stahl LinzGmbH, Austria

Advanced vehicle concepts and designs in automotive industry re-quire improved steel grades with increased strengths. Challenges inimplementing these new materials, such as AHSS steels come in

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 186

Wed

nes

day

AM

www.matscitech.org 187

forming, while the increase in strength is generally coupled with thedecrease in material formability. One of the methods characterizingformability of sheet materials is hole expansion testing. An instru-mented hole expansion testing device was constructed in order to op-timize and unify this industrially widely applied testing method. Sev-eral device parameters, such as clamping force, penetration depth,lubrication, punch geometry, etc. were investigated. Industrially pro-duced dual-phase and complex-phase steel grades with tensilestrengths of 600 and 800MPa were selected for the trials. Specimenswith standard geometry and punched and wire cut holes were ana-lyzed. The experimental results are compared and discussed with re-spect to the impact of varied device parameters as well as the influ-ence of material microstructure and mechanical properties.

11:00 AMBake Hardening Steel (BH220) CharacterizationS. Ghosal*, B. R. Galgali, S. P. Joshi, M. M. Ogale, Tata Motors, India

The bake hardening effect depends on three parameters i.e. pre-strain-ing, paint baking temperature and paint baking time. The combinedeffect of all these parameters results into the increase in yield strength,called the “baking effect”. This paper explains the individual effects ofthese parameters on the baking value. Tensile test were carried out forthe 88 samples baked at varrying baking temperature, time and pre-strain. The differences of yield strength between the unbaked andbaked sample were calculated and the increase in yield strength wasnoted. This would help shop floor optimization of the process param-eters and the compatibility with various painting process Vis a Vis in-crease in bake hardening strength. It is also leading to a future work tounderstand clearly the correlation between the baking temperature,increase in strength and the micro structural changes.

11:20 AMReception of Borized Coatings Eutectic Type on Steel inConditions Self-propagating High-temperature SynthesisB. Sereda*, ZSEA, Ukraine

The researches have shown, the eutectic structured coatings are formednear the solidus. On steel the eutectic borized coatings could be re-ceived in areas above and below to temperatures of double eutectic (α-phase+Fe2B) in system Fe-B. The thickness of received borized coat-ings makes to 1.5 mm. The borized coatings is eutectic mix of α-phaseborides FeB, Fe2B and boron cementite Fe3 (C, B). On a surface thephases FeB and Fe2B is mainly fixed. The average score of fragility andparameter of fragility γ100 mainly depends on condition of superficialphase (FeB) and its quantities. For hypoeutectoid steel(0,45 %C) aver-age score of fragility γ100 = 1,4. With the increasing of temper in steelthe average score of fragility decreases for 10-20 %. Microhardness ofcoverings is H100 = 16000 MPa, and on arias of complex alloyed per-lite H100 = 6000-7000 MPa. Use of non-stationary conditions of SHS-process allows not only to accelerate saturation of a surface by boron,but also to receive coatings with the set phase structure and properties.

Iron & Steel: Refractory Innovations andNovel Applications in Iron & SteelManufacture

Refractories for Iron and Steel IRoom: 329Session Chair: Dana Goski, Allied Mineral Products

10:00 AMComposite Design Technology Development for HighPerformance Sliding Gate MaterialsP. G. Desai*, M. R. Snyder, D. L. DeBastiani, Vesuvius, USA

Over the past decade, materials performance in ladle slide gate appli-cations has increased significantly. In this period, the improvementshave been obtained through use of additives and process technology

enhancements in a single-mix plate. However, the single-mix platerepresents a compromise; mix additives that promote thermal shockresistance generally tend to reduce corrosion resistance or sliding sur-face wear resistance. This paper will present one effective approach toimprove the performance of sliding gate materials through use ofComposite Design Technology or CDT. CDT involves design of amulti-mix composite in a single automated forming step that seeks toimprove overall plate performance through effective use of multiplemixes in a one-piece refractory. While this technology has been suc-cessfully utilized in Europe and Asia, there is scope for leveraging thistechnology in the North American steel plants.

10:20 AMCasthouse Refractory SystemsY. C. Ma, R. G. Brenneman*, C. R. Larkin, F. R. van Laar, Allied MineralProducts, Inc., USA

This paper will discuss the impact of casthouse refractory designs andthe dynamic behavior of the overall system on casthouse refractoryperformance. The significance of different cooling systems, optimiz-ing refractory configuration and the evolution of casthouse refrac-tory materials to the current technology state are all discussed. Differ-ent systems and strategies to monitor the condition of the refractoryand containment structures will also be reviewed.

10:40 AMLow temperature oxidation on magnesia carbon brickY. M. Lee*, ArcelorMittal Steel, USA

Antioxidant metals have been used to protect the carbon bond in mag-nesia carbon bricks from oxidation. Antioxidant metals melt to protectthe carbon bond between magnesia grains above ~700 degree C. How-ever, antioxidant metals can not protect the carbon bond if they do notmelt at low temperature. This type of low temperature oxidation sig-nificantly reduces the mechanical strength of magnesia carbon bricksto lead catastrophic failure during use. Low temperature oxidation be-havior on magnesia carbon was investigated and will be presented.

11:00 AMModeling of Thermo-Mechanical Effects of Covering a LadleDuring Continuous Casting on Refractory BehaviorW. L. Headrick*, Missouri Refractories, USA; A. R. Hanifi, University ofLimerick, Ireland; A. Eilaghi, A. Salary, F. Golestani-Fard, Iran University ofScience and Technology, Iran; J. Canon, Wahl Refractories, USA

Thermo-mechanical effects of putting a lid on a ladle during castingon the refractories behavior will be discussed in the present work. It isimportant to steel makers that steel vessels have a long life. In this re-gard, it is necessary to comprehend the thermo-mechanical behaviorof refractories and their resistance to harmful thermal shocks. The re-sults of this research show that covering the ladle during casting savesthe heat in the refractory body but slightly increases the level ofstresses in this stage. The positive influences of using a lid in castingprocess appear during stopping time and after converter tapping. It isconcluded that using lids can affect the ladle rotation program andimprove the performance of the steel plant system considerably.

11:20 AMAn Attempt to Enhance BOF Productivity: Role of Hot MetalTransfer Ladle Lining at Durgapur Steel PlantS. Sarkar*, T. K. Pal, N. K. Ghosh, S. K. Garai, P. Chintaiah, M. K. Kujur, P. K.Dutta, A. N. Misra, Sreel Authority of india Limited, India

Newly relined hot metal transfer ladle is capable of carrying 140t liq-uid metal for producing 130t steel. The study reveals that the lininggradually builds up metal jam resulting increase in tare weight ofladle by 20t before it goes down for repair. The reduction in chargecapacity diminishes the BOF shop productivity. Experiment madewith modified lining design and application of Al2O3-SiC-C refrac-tories in critical zones both in the form of bricks and monolithics re-placing high grog bricks. Insulation was provided to arrest heat loss.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 187

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania188

Result shows easy metal jam removal due to non-stickiness of Al2O3-SiC-C refractories and is in circulation for a longer duration with ahigher heat capacity of converter. The first experimental ladleachieved a record life of 2443 heats vis-a vis 1200-1300 heats linedwith conventional refractories. The paper deals with the details ofmodifications made and its benefits towards achieving higher heatsize in BOF converters.

Materials & Systems: Advances in Biomedicaland Biomimetic Materials

Surface Modification of BiomaterialsRoom: 333Session Chairs: Bret Chisholm, North Dakota State University;Shane Stafslien, North Dakota State University

8:00 AMPolysiloxane Coatings Containing Tethered AntimicrobialMoieties (Invited)B. Chisholm*, P. Majumdar, S. Stafslien, J. Daniels, A. Kugel, North DakotaState University, USA

Using combinatorial methods, we have developed an understandingof the various compositional variables needed to generate surfacechemical compositions and surface morphologies that providedpolysiloxane coatings that exhibit broad spectrum antimicrobial ac-tivity without the use of leachable antimicrobial agents. The compo-sitional space that was explored was based on moisture-curable poly-siloxanes derived from silanol-terminated polydimethylsiloxane(PDMS) polymers and quaternary ammonium salt (QAS)-functionaltrimethoxysilanes. All variables, which included QAS concentration,QAS chemical composition, and silanol-terminated PDMS molecularweight, were thoroughly investigated. The results of the studiedshowed that all factors affected the antimicrobial activity of the coat-ings. A correlation between coating surface morphology and antimi-crobial activity was observed. Coating compositions that resulted inhighly heterogeneous surface morphologies were found to possess thegreatest antimicrobial activity.

8:20 AMSurface Modification of Implantable Neural Electrode Arrays(Invited)X. T. Cui*, A. Erdrin, C. F. Lagenaur, University of Pittsburgh, USA

Silicon based neural electrode arrays experience failure in long-termrecording due to poor biocompatibilty. One of the strategies beingexplored in our lab is surface modification using neural adhesionmolecule L1 and polyethyleneglycol (PEG). Silane and 4-Maleimi-dobutyric acid N-hydroxy succinimide ester (GMBS) were used tobind L1 on the surface of the arrays. PEG-NH2 was used to inactivatethe reactive GMBS and inhibit non-specific protein adsorption andcell adhesion. It was found in vitro that L1-PEG surface promotedneuron growth and neurite extension, but inhibited astrocyte growth.Modified neural probes were implanted in the rat brains for 1 or 4weeks. Immunohistochemical staining of the tissue sections revealeda significant increase in neurofilament and a reduction of astrocyticreaction around the modified probes. High neuronal density and re-duced astrocyte reactivity around the neural probes may lead to morestable and higher quality chronic neural recording.

8:40 AMCombinatorial/High-Throughput Methods for the RapidDiscovery of Antimicrobial Coatings and Materials for BiomedicalApplications (Invited)S. J. Stafslien*, B. Chisholm, P. Majumdar, J. Bahr, J. Daniels, D. Christianson,North Dakota State University, USA

A significant effort has been initiated to develop new and effective an-timicrobial coatings for implanted medical devices using a combina-

torial approach. Our research program is primarily focused on thedevelopment of contact active or non-leaching coating technologies.A high-throughput microbial biofilm growth and retention assay hasbeen developed to adequately accommodate the large numbers ofcoating generated with a combinatorial approach. Coating arrays areprepared in multi-well plates and challenged with a variety of mi-croorganisms associated with infection and failure of implantedmedical devices. A series of contact active antimicrobial coatings havebeen developed using the combinatorial workflow and were analyzedwith the high-throughput microbial biofilm growth and retentionassay. Several coating candidates exhibited excellent reduction in mi-crobial biofilm growth without the presence of leachate toxicity.

9:00 AMSurface Modification of Biomaterials Using Electro PlasmaTechnologyP. George*, CAP Technologies LLC, USA; V. Singh, Louisiana State University,USA; E. Daigle, CAP Technologies LLC, USA

Electro Plasma Technology (EPT) is an effective process for surfacemodification of metallic biomaterials. EPT is essentially a hybridprocess for cleaning, coating and surface modification of variousmetallic materials. It has been shown that EPT can create differentsurface morphologies on the same surface by varying the process pa-rameters. The unique nano-features created on surface with EPT pro-duces an excellent adhesion between the substrate and the coating.EPT can be also used to rapidly deposit nano-crystalline metallic andceramic coatings including hydroxyapatite, at rates as high as 1μmper second. The present study will discuss the effect of process pa-rameters, such as electrolyte composition and processing time, on thesurface morphology of 316 stainless steel and titanium alloy, the twobiomaterials extremely popular in the biomedical community. Sur-face morphology of the processed materials was studied using scan-ning electron microscope and surface profilometer.

9:20 AMInfluence of Mg and Y dopants on electrical polarization ofhydroxyapatite ceramicsS. Bodhak*, S. Bose, A. Bandyopadhyay, Washington State University, USA

The objective of this work is to investigate the influence of doping ofmultivalent cations, Mg2+ and Y3+, on polarization behavior of sin-tered hydroxyapatite (HAp). HAp samples were sintered at 1250oCfor 2h and subsequently polarized via application of an external dcfield (1 KVcm-1) at 400oC. The sign and magnitude of induced sur-face charges depend on applied dc field. Thermally stimulated depo-larization current (TSDC) technique was used to measure the storedcharge. A variety of stored charges (~ 2.1 to 5.8 μC/cm-2) was meas-ured depending on dopants, while pure HAp showed maximumcharge (~ 9 μC/cm-2). SEM and FTIR analysis were done to study theinfluence of polarization of both doped and undoped HAp on apatitegrowth under simulated physiological condition for 1, 5 and 7 days.Irrespective of dopants used, accelerated crystal growth on negativecharged surface, and decelerated apatite growth on positive chargedsurface were observed.

10:00 AMMolecular Modulation in Biomaterials (Invited)R. Qiu*, Lawrence Livermore National Laboratory, USA; M. Weaver,University of California, USA; R. Friddle, Lawrence Livermore NationalLaboratory, USA; A. Wierzbicki, University of South Alabama, USA; W.Casey, University of California, USA; J. De Yoreo, Lawrence Berkeley NationalLaboratory, USA

Biological systems have the ability to produce materials solutions totheir functional requirement by fabricating sophisticated hierarchicalstructures. Understanding the molecular mechanism by which smallmolecules and macromolecules modulate the shape of biogenic ma-terials is essential to provide rational strategies for designing and syn-thesizing biomimetic materials and engineering crystals. Over the

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 188

Wed

nes

day

AM

www.matscitech.org 189

past decades we have used in situ AFM to investigate the physics ofshape control by observing the growth of calcium carbonate, calciumphosphate, and calcium oxalate single crystals in the presence ofsmall inorganic modifiers, peptides, and proteins. We find that themolecular scale interaction that drives shape modification occurs be-tween the additives and the steps edges on existing crystal faces. Inthis presentation, we will show examples from a number of modelsystems of biogenic materials to illustrate the molecular scale modu-lation with the emphasis on the calcium oxalate, a major constituentof human kidney stones.

10:20 AMInterfacial Energetics of Protein Adsorption from Aqueous Bufferto Surfaces with Varying Hydrophilicity (Invited)P. Cha*, E. Vogler, V. Fiore, Penn State University, USA

Time-and-concentration-dependent advancing contact angle θ°(a)isotherms (AI) show little effect of biochemical diversity among 10proteins spanning 10-1000 kDa MW on amount adsorbed fromphosphate-buffered saline (PBS) solution after 1 h contact with sur-faces of various wettability (per PBS adhesion tensionτ°(a)=γ°(lv)cosθ°(a); where γ°(lv) is liquid-vapor (LV) interfacialtension and θ°(a) is of pure PBS). Max. spreading pressure,Π(a)^max (from AI) decreases with τ°(a) for hexadecanealkanethiolmonolayers (τ°(a)=-15 mN/m), polystyrene (7.2 mN/m), amino-propyltriethoxysilaned (42 mN/m), and fully-wettable SiOx (72mN/m). Likewise, apparent Gibbs’ excess [Γ(sl)-Γ(sv)], or differencebetween adsorbed amount Γ (mol/cm^2) for solid-vapor and -liquid(SV&SL) interfaces, decreases with τ° through 0 near τ°=30 mN/m(θ°(a)=65°). Results corroborate findings that protein cannot dis-place water bound to τ°≥30 mN/m surfaces, a finding applicable todisparate protein-compositions.

10:40 AMAdvances in Surface Modification of Biomaterials (Invited)V. Singh*, Q. Nguyen, T. Monroe, J. Goettert, Louisiana State University, USA

In the immediate past the miniaturization and rapid prototypingusing state of the art techniques have fueled the development of thebiomedical devices. These techniques use more than one material tofabricate the devices, which may affect their biocompatibility. In thispresentation we explore the recent advances in the area of surfacemodification of bulk as well as the nano structured biomaterials. Thisstudy discusses the immense potential of Diamond-like Carbon andParylene biocompatible coatings in playing a crucial role in revolu-tionizing the development of the biomedical devices by providing theuniform and functional biocompatible material across the whole sur-face. Also this will discuss the effect of plasma based nano patterningand/or surface modifcation of these biocompatible coatings.

11:00 AMUse of dye-embedded silicone elastomers to prevent CathetersRelated InfectionsC. Piccirillo*, I. P. Parkin, S. Perni, M. Wilson, J. Pratten, University CollegeLondon, United Kingdom

In this paper we describe how embedding a dye (methylene blue –MB) into catheter material (silicone elastomer) reduces bacteria ad-hesion on the catheter surface. Furthermore, if irradiated with an ap-propriate laser source, MB shows an antimicrobial effect, resulting inthe killing of the bacteria. Therefore, this can reduce the incidence ofCatheter Related Infections. The embedding of MB into the elas-tomers was performed with the swell encapsulation methodology. Afull characterisation of the samples was done with several analyticaltechniques. The MB bactericidal properties were tested on differentbacteria (i.e. MRSA, E. coli). Results showed a decrease in the bacteriaconcentration up to 3 orders of magnitude after less than 10 minutesof laser irradiation. MB-embedded silicone elastomer can be success-fully used as catheter material having antibacterial properties; therewould reduce the development of CRI.

11:20 AMChemical-Hydrothermal Combined Synthesis of Bioactive TiO2and CaTiO3 Films on Ti SurfacesM. Ueda*, M. Ikeda, Kansai University, Japan; M. Ogawa, Daio Steel Co.,Ltd, Japan

The chemical-hydrothermal combined synthesis of TiO2 andCaTiO3 films on pure Ti substrates was examined with a focus oncrystallinity and surface morphology of the films. Pure Ti disks werechemically treated with H2O2/HNO3 solutions at 353 K for 20 minin order to introduce a TiO2 layer with low crystallinity on the sur-face. The samples were then hydrothermally treated in an autoclave at453 K for 12 h. Anatase-type TiO2 and perovskite-type CaTiO3 filmswith high crystallinity were obtained upon treatment with distilledwater and an aqueous solution of Ca(OH)2, respectively. In addition,in vitro formation of hydroxyapatite (HAp) on the films was investi-gated. Obtained samples were immersed in SBF (Simulated BodyFluid), adjusted to 310 K. The present surface modifications wereconfirmed to drastically promote the deposition of HAp on the sur-face. The surfaces also showed excellent adhesion of osteoblast-likeMC3T3E1 cells.

11:40 AMTribological Behavior of Titanium Alloys in BiocompatibleSolutionsS. N. Paul*, Visvesvaraya National Institute of Technology, Nagpur (VNIT),India; S. Sahu, Indian Institute of Technology, India; M. Roy, DefenceMteallurgical Research laboratory, India

The use of titanium & its alloys for biomedical applications is in-creasing due to their low elastic modulus, superior biocompatibil-ity and enhanced corrosion resistance. Friction and wear play animportant role in determining the performance of biomaterials.Present investigation is therefore carried out to study the tribo-logical behavior of different titanium alloys in stimulated solu-tions. The reciprocities wear test were carried out on CP-Tita-nium, Ti-6Al-4Fe, Ti-13Nb-13Zr, Ti-18Nb-4Sn,Ti-13Ta-29Nb-4.6Zr. The wear test were performed in Hank’s,Hank’s with albumin, Ringer, Ringer-with bovine serum albuminto assess the performance of the material in stimulated bodyfluid(physiological)solutions. All the titanium alloys exhibit com-patible wear behavior in stimulated body fluid solutions. There-fore these titanium alloys have very high potential for biomedicalapplication.

Materials & Systems: Enabling SurfaceCoating Systems: Science and Technology

Environmental Barrier CoatingsRoom: 335Session Chair: H.T. Lin, Oak Ridge National Laboratory

8:00 AMFlexible Approach to Selecting and Applying EBC Coating Systemsfor Application at Elevated Temperatures (Invited)C. A. Lewinsohn*, B. Nair, H. Anderson, Ceramatec, Inc., USA

Deleterious reactions with the ambient environment often limit thelifetime of materials utilized at elevated temperatures. For example,the lifetime of silicon-based ceramic components may be limited byhydrothermal corrosion. Conditions leading to hydrothermal corro-sion are common in combustion environments and several other ap-plications related to power generation. Often, materials with ade-quate resistance to hydrothermal corrosion, or otherenvironmentally-induced failure mechanisms, do not possess the re-quired mechanical properties to be used as engine components, butthey may perform satisfactorily as coatings. Unfortunately, reliable

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 189

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania190

coatings of these materials are not possible due to significant prop-erty mismatches with desired substrate materials. Likewise, interlay-ers, and methods of applying them, to accommodate property mis-matches, must be compatible with both the substrate and coatingmaterials and not inhibit their performance.

8:40 AMDevelop SiAlCN Ceramics for Environmental Barrier CoatingApplications (Invited)L. An*, University of Central Florida, USA; Y. Wang, NorthwesternPolytechnical University, China

Si-based ceramics are promising materials for high-temperature ap-plications. However, usages of these materials are limited by their sen-sitivity to oxidation and water-vapor induced corrosion. One way tosolve the problem is to coat the materials with so-called environmen-tal barrier coatings (EBCs). Materials which can be successfully usedfor EBC applications need to fulfill a few requirements, includinghigh oxidation/corrosion resistance, high-temperature stability, ther-mal match with the substrate materials, and low oxygen permeability.In this paper, we present our recent results on the oxidation and cor-rosion behavior of polymer-derived SiAlCN ceramics. We found thata certain amount of Al can drastically improve oxidation/corrosionresistance of the materials. Mechanisms underlying such improve-ments have been proposed. Given the high-temperature stability andflexibility of PDC processing, SiAlCN could be an excellent candidatefor EBC applications.

9:20 AMEvaluation of the Corrosion Resistance of Fe-Al-Cr Alloys in aSimulated Coal Combustion EnvironmentR. Deacon*, Johns Hopkins University Applied Physics Lab, USA; J. DuPont,C. Kiely, A. Marder, Lehigh University, USA; P. Tortorelli, Oak Ridge NationalLaboratory, USA

Iron aluminum alloys have recently been identified as inexpensive al-ternatives to nickel based alloys for use as corrosion resistant weldoverlays in coal combustion environments. The role of chromium ad-ditions to FeAl alloys in these environments has not been conclusivelyidentified. In the present work, FeAlCr alloys were exposed to a simu-lated coal combustion environment for up to 5,000hours. Scanningand transmission electron microscopy of corrosion products revealedthat the addition of chromium greatly improved the corrosion resist-ance by suppressing formation of iron sulfide. At higher aluminumconcentrations, a thin (less than 100nm) layer of chromium oxidewas observed to encapsulate surface sulfide products, offering an ad-ditional mechanism for reducing further corrosion. The results indi-cate a critical concentration of both aluminum and chromium are re-quired for the long term corrosion resistance of iron based weldoverlays in coal combustion environments.

10:00 AMEffect of gelatin additions on the corrosion resistance of ceriumbased conversion coatingsW. Pinc*, P. Yu, M. O’Keefe, W. Fahrenholtz, T. O’Keefe, Missouri Universityof Science and Technology, USA

The addition of organic gelatins to the precursor solution used tospray deposit cerium based conversion coatings on Al 2024-T3 sub-strates was found to influence the corrosion performance of the coat-ing. It was determined that coatings deposited from solutions con-taining gelatin exhibited better corrosion resistance in salt fog andelectrochemical testing compared to coatings made without the addi-tive. The difference in corrosion protection was related to the re-sponse of the coatings to post-deposition treatment in a sodiumphosphate solution used to convert the hydrated cerium oxidespecies in the as-deposited coating to hydrated cerium phosphate.After post-treatment, energy dispersive spectroscopy showed thatcoatings deposited from solutions containing gelatin had a higherphosphorus to cerium ratio than coatings made without gelatin, in-

dicating conversion into cerium phosphate was more complete, andhad better corrosion performance, when gelatin was used in the coat-ing solution.

10:20 AMEffect of Phosphate Source on the Post-treatment of Cerium BasedConversion Coatings on Al2024-T3D. Heller*, M. O’Keefe, W. Fahrenholtz, Missouri University of Science andTechnology, USA

Phosphate-based post-treatments are used to improve the corro-sion resistance of cerium based conversion coatings on highstrength aluminum alloys. Salt spray results show that corrosion re-sistance is dependent on the type and concentration of phosphatesalt used to prepare the post-treatment solution. Other factors, suchas immersion time, temperature, and solution pH also impact cor-rosion performance. To better understand their effects, sponta-neous spray deposited cerium based conversion coatings were char-acterized after sealing. Electrochemical characterization, includingpotentiodynamic response and impedance spectra, was used toevaluate the coatings in addition to physical and chemical analysis.These analyses are then correlated to observations of panels sub-jected to neutral salt spray testing for 14 days in accordance withASTM B117.

10:40 AMThe effect of phosphate additions on the corrosion resistance ofcerium conversion coatings on aluminum alloy 7075 – T6S. Joshi*, M. O. Keefe, W. G. Fahrenholtz, T. O. Keefe, Missouri University ofScience and Technology, USA

Cerium conversion coatings have been identified as a potential candi-date to replace chromate conversion coatings for protecting alu-minum alloys. The coatings can be deposited by spraying a water-based solution of a soluble cerium salt onto aluminum alloy panels.Normally, the coated panels are treated in a hot sodium phosphatesolution to improve the corrosion resistance. This research is focusedon the effect of adding phosphate species to the coating solution inaddition to the post-deposition treatment in phosphate solution.Panels coated using this new method had improved corrosion resist-ance based on both salt spray testing and electrochemical measure-ments. Scanning electron microscopy also showed that the coatingshad fewer cracks and the cracks that were present were smaller. Basedon these observations, phosphate additions to the coating solutionmay result in a coating that is more resistant to cracking and corro-sion in chloride environments.

11:00 AMEffect of Al Addition on the Structure of Vapor-DepositedStainless Steel-Aluminum CoatingsU. R. Seelam*, C. Suryanarayana, University of Central Florida, USA; N.Sastry, R. Wei, Southwest Research Institute, USA

The oxidation resistance of stainless steel turbine components can beincreased by overlay surface coatings. In the present study, SS304stainless steel samples were coated with stainless steel containing dif-ferent amounts of Al, viz., 0, 3, 7 and 10 wt.% by physical vapor dep-osition using plasma enhanced magnetron sputtering technique. Theas-deposited coatings were characterized by XRD, SEM and TEMtechniques. All the coatings had columnar grain structure with theircolumn width increasing with Al content. In the absence of Al in thecoating, the microstructure consisted of the α-Fe solid solution phaseand a tetragonal precipitate phase with a size range of 5-50 nm, iden-tified as σ-FeCr. With increasing Al content from 3 to 10 wt.%, in ad-dition to the α-Fe solid solution, the coating contained the orderedFeAl phase, the quantity of which, increased with higher Al content.In summary, Al seems to have a significant effect on the microstruc-ture of the stainless steel coatings.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 190

Wed

nes

day

AM

www.matscitech.org 191

11:20 AMComparison of HVOF sprayed CoNiCrAlY coating on Incoloy 909and Inconel 718B. Mettupalayam*, K. Shanker, Standard Aero, Canada; N. Richards,University of Manitoba, Canada

MCrAlY coatings are extensively used in gas turbine engines (GTE) toimprove oxidation resistance of Superalloys at extreme service condi-tions. It is generally an accepted practice to choose optimal MCrAlYcoating based on the application requirements and not on substratephysical properties such as coefficient of thermal expansion (CTE). Itis believed that CTE of various MCrAlY and Superalloys are willwithin the compatible range that the likelihood for coating interfaceseparations is negligible. Low CTE Superalloys such as Incoloy 909are attractive to improve efficiency of GTE but can be incompatibleto traditional MCrAlY type coatings. This study was undertaken toinvestigate a MCrAlY coating applied by HVOF deposition on awidely used Superalloy (Inconel 718) and a low CTE Superalloy (In-coloy 909). The various factors such as CTE, ductility, and oxidationeffects were investigated and the result favors Inconel 718 comparedto the other alloy.

11:40 AMHigh Temperature Corrosion of some Ni-Base Superalloys in thePresence of ZnSO4G. Goyal*, Government College of Engineering & Technology, India; R.Gupta, Government College of Engineering and Technology, India; H. Singh,BBSB Engineering College, India; S. Prakash, Indian Institute of TechnologyRoorkee, India

High temperature corrosion is an accelerated form of corrosion oc-curring at higher temperatures. Superalloys are used to resist this typeof corrosion and success has been achieved to a considerable extent,however they still lack resistance to hot corrosion. Inhibitors havealso been used with varying success to combat the same. In the pres-ent investigation, hot corrosion studies were conducted on two Ni-base superalloys namely Superni 718 and Superni 601 in a simulatedenvironment of boilers (Na2SO4-60%V2O5) with and without thepresence of ZnSO4 as an inhibitor. The hot corrosion tests were car-ried out under cyclic conditions at 900C for 50 cycles, and the corro-sion products were characterized by SEM, XRD and EPMA analyses.The ZnSO4 addition resulted in a marginal reduction in corrosionrate for both the alloys. In the alloy Superni 718, a Cr2O3 layer wasseen just above the substrate, whereas for the alloy Superni 601, theCr-rich layer was thin, irregular and discontinuous layer.

Materials & Systems: InternationalSymposium on Innovative Processing andSynthesis of Ceramics, Glasses andComposites

Rapid PrototypingRoom: 336Session Chair: John Halloran, University of Michigan

8:00 AMCeramic Manufacture By Photopolymerization: StereolithographyAnd Large Area Maskless Photopolymerization (Invited)J. W. Halloran*, C. Torres-Garibay, V. Tomeckova, C. Bae, University ofMichigan, USA; S. Das, Georgia Institute of Technology, USA

Ceramic parts with complex external shapes and internal spaces canbe fabricated by layered manufacturing methods based on the pho-topolymerization of monomers containing ceramic powders. We willreview previous work on various application, and present recentprogress on a program to develop a commercial production of invest-ment casting molds from ceramic stereolithography using a commer-cial machine. We will present design of a more advanced technology

based on an advanced large area maskless photopolymerization sys-tem and discuss early results on the materials and fabrication. We willdiscuss the fundamentals of the photopolymerization process and thepractical details for several cases.

8:40 AMIntegrally Cored Ceramic Investment Casting Molds fabricated byCeramic StereolithographyC. Bae*, J. W. Halloran, University of Michigan, USA

Superalloy airfoils are produced by investment casting, which useceramic cores and wax patterns with ceramic shell molds. As an al-ternative for small production runs or designs too complex forconventional cores and patterns, we use ceramic stereolithography(CerSLA). CerSLA is an extension of the standard RP process ofstereolithography, using a photopolymerizable suspension of ce-ramic powders. Using the layer-by-layer growth enabled by Cer-SLA, it is possible to eliminate the pattern and produce a one-piece mold integrated with the core, or an Integrally CoredCeramic Investment Casting Mold (ICCM). We report on the na-ture and properties of the photopolymerizable suspension for re-fractory silica powders and the processing steps after CerSLA fab-rication (draining, binder removal, sintering). Examples ofcomplex ICCM shapes are presented, with data on accuracy andreproducibility. Progress with superalloy casting in the ICCM willbe briefly discussed.

9:00 AMCriteria for preventing segregation in layers built by CeramicStereolithography (CerSLA) : Degree of segregation parameter (ββ)C. Bae*, J. W. Halloran, University of Michigan, USA

Ceramic stereolithography (CerSLA) is a repeated layered manufac-turing process where thin liquid layers of powder in monomer aresolidified by photopolymerization with a UV laser, thereby “writ-ing” the design for each slice. Using refractory powders generatessegregation which is affected by the two competing factors; settlingtime of powder and writing time of a layer. Segregation in layerscan be preserved if the time required for the suspended particle tosettle a layer thickness is longer than the time required to write alayer. In this paper we derive the degree of segregation parameter(β), which is dependent on design factors (surface area and layerthickness), apparatus factors (laser power), and material factors(particle size distribution and resin sensitivity) to suppress segrega-tion in layers. Finally, given the degree of segregation parameter(β), the criteria for preventing segregation in layers built by CerSLAare presented.

9:20 AMTerpene-based Thermoreversible Photocurable Vehicle forCeramicsV. Tomeckova*, C. Torres-Garibay, J. W. Halloran, University of Michigan, USA

New material based on unique combination of terpenes such as cam-phene and camphor along with UV curable acrylate monomers wasdeveloped and can serve as a thermally reversible photocurable vehi-cle for ceramics. Compositions have to exhibit low viscosity at highertemperature 65 – 100°C, enough crystalline strength at room temper-ature and cured strength when polymerized. This can be onlyachieved when exact proportion of acrylate monomer and terpenes isused. At room temperature we assume existence of “interdendritic”liquid – monomer trapped in terpenes dendritic network. Up to 25acrylate monomers were tested for their suitability to meet basic re-quirements - liquidity/solidity at higher/room temperature, respec-tively. Water-dispersible monomers are of particular interest becausethey show better affinity to polar substances such as camphene. Can-didate vehicle was loaded with ceramic up to 50 vol.%, tape castedand photopolymerized upon solidification.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 191

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania192

10:00 AMTerpene System-Acrylate Monomer Phase-ChangePhotopolymerizable Material CompositionsC. Torres-Garibay*, V. Tomeckova, J. W. Halloran, University of Michigan, USA

Phase-change photopolymerizable materials (PCPM) containing acurable monomer are potential organic vehicles for ceramic particlesin digital manufacturing techniques. For ease of processing, the pre-ferred transition temperature is between room temperature and 100°C. PCPM are prepared and processed in the liquid state, and pho-topolymerized when they are solid. Hexanediol diacrylate (HDDA) isused as curable media, whereas a terpene system provides the phasechange characteristics. Camphene, which melting point is 44-48 °C, isvery soluble in presence of HDDA. Camphor, a terpenoid derived fromcamphene with melting temperature 173-175 °C, has been added tothe mix to reduce the solubility of camphene. Phase relationships be-tween HDDA, camphene and camphor are studied, and those compo-sitions who exhibit a solid phase at room temperature and liquid phaseat 100 °C are considered as PCPM. Solidification behavior and pho-topolymerization characteristics of these compositions are explored.

10:20 AMCharacterization of Highly Loaded PhotopolymerizableSuspensionsC. Torres-Garibay*, V. Tomeckova, C. Bae, J. W. Halloran, University ofMichigan, USA

Photopolymerizable ceramic suspensions for near net shape process-ing techniques require high solids volume fraction (φ) to producedense bodies. These suspensions must exhibit low viscosity duringprocessing. The type of monomer and dispersant amount influencethe viscosity of the system, whereas the photopolymerization behaviorof the suspension is highly determined by the monomer characteristicsand the optical scattering properties of the particles. Highly loaded (φ= 60 %) silica photopolymerizable ceramic suspensions were preparedby ball milling. The viscosity of the suspension was characterized interms of dispersant amount and time of ball milling. The curable com-ponent was one of two monomers with different functionalities andviscosities (hexanediol diacrylate and ethoxylated (4) pentaerythritoltetraacrylate), or a combination of them. Photopolymerization behav-ior, cure depth, polymerization kinetics, and properties are reportedusing direct measurements, photoDSC, and photorheology.

10:40 AMShrinkage During Polymerization of Ceramic SuspensionsV. Tomeckova*, C. Torres-Garibay, C. Bae, J. W. Halloran, University ofMichigan, USA

Complex ceramic shapes can be produced by polymerization of highlyloaded ceramic suspensions in monomer solutions, using thermalpolymerization for gel-casting or photopolymerization for layeredmanufacturing. This paper considers shrinkage during photopolymer-ization, resulting from double bond conversion of monomer in thesuspension medium. The degree of shrinkage is crucial with respect todistortions during photopolymerization and the final dimensions ofceramic green bodies. We propose a model relating polymerizationshrinkage measured via changes in density before and after curing toceramic volume fraction, particle size distribution, and the density andfunctionality of the monomer. Precise study of polymerization shrink-age can be adopted as a useful tool for calculation of double bond con-version percentage and calculation of critical minimum energy re-quired for photopolymerization, which is in good agreement withcritical energy values obtained from penetration depth measurements.

11:00 AMQuantifying particle size segregation by differential sedimentationof powderC. Bae*, J. W. Halloran, University of Michigan, USA

Suspensions of coarser or denser particles can undergo differentialsedimentation, leading to particle size segregation in which the popu-

lation of larger or denser particles is greater near the bottom. Thusthe particle size distribution changes with vertical position. We pres-ent data on SiO2 powders in repeated layers. Long time with coarseparticles induces repeated pattern of severe segregation with totallyseparated two regions in the green body: particle free zone at the topand segregated SiO2 powders at the bottom of the layers. However,shorter time with bimodal particles generates much less segregationso that only subtle patterns. This paper considers the influence of set-tling time and particle size distribution on the segregation in layersand addresses methods to quantify the segregation, with particularemphasis on extracting a Homonization index H by combining scat-tered data from many sequential layers.

11:20 AMRF processing for low energy glass, armor, and solar panellaminationS. M. Allan*, M. L. Fall, H. S. Shulman, Ceralink Inc, USA

Radio frequency lamination was developed for rapid processing oftransparent ceramic armor and solar panels. The process uses an RFpress, which combines RF heating and uniaxial pressure, to quicklyproduce laminates. The RF energy penetrates glass and ceramic sub-strates, and produces heat in the vinyl interlayers. Pressure was simul-taneously applied. Lamination time was less than 1 minute for severalvariations of single and multilayer laminates (glass-vinyl-glass, orglass-vinyl-insert-vinyl-glass). As a result of fast processing, 95% lessenergy was consumed compared to autoclaving. Glass, ceramics, andplastics were laminated using the RF process. Functional and decora-tive inserts of solar cells, fabrics, and printed films were inserted intothe laminates using RF lamination.

Nanotechnology: Controlled Processing ofNanoparticle Structures and Composites

Nano-enabled FilmsRoom: 408Session Chair: Ian Nettleship, University of Pittsburgh

8:00 AMProcessing, Microstructure, and Mechanical Behavior of TiO2Nanotubes on Ti (Invited)G. Crawford, N. Chawla*, Arizona State University, USA

TiO2 nanotubes exhibit remarkable photoelectrochemical, gas sens-ing, and biological properties. The properties of TiO2 nanotubes arecontrolled, in large part, by their large surface-to-volume ratio andlarge aspect ratio. In this talk we report on processing, microstruc-ture, and deformatin behavior of TiO2 nanotubes grown on pure ti-tanium substrates through anodic oxidation. By adjusting the pro-cessing conditions, the coating thickness, tube diameter and tube wallthickness were varied. Characterization of the as-processed coatingswas conducted using SEM, FIB, and TEM. Nanoindentation, using anInterfacial Force Microscope, was employed to accurately probe theYoung’s modulus of the nanotubes. This technique was also used tostudy the inelastic deformation behavior of the nanotubes. The rela-tionship between the processing parameters and nanostructure of thetubes will be described. The influence of the nanostructure on themechanical response of the tubes will be discussed.

8:40 AMReversible Transition from Superhydrophobic toSuperhydrophilic SU8 Pillars Using TiO2 NanocrystalsG. Caputo*, B. Cortese, C. Nobile, L. Manna, R. Cingolani, A. Athanassiou, D.P. Cozzoli, NNL-ISUFI University of Salento, Italy

During the last years, the attention towards superhydrophobic andsuperhydrophilic surfaces has attracted a tremendous increasing rateof publications due to their possible application in diverse technolog-ical fields such as for microfluidics, self-cleaning and biological de-

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 192

Wed

nes

day

AM

www.matscitech.org 193

vices. In this contribution we present different SU8 pillars-structuredsurfaces covered by TiO2 nanorods (NRs), which are able to improvethe initial hydrophobicity of the pillars, water contact angle (WCA)~150°, and simultaneously to undergo a superhydrophilic reversibletransition using selective UV laser irradiation (WCA ~10°). By com-bining diverse investigations, the wettability changes have been as-cribed to an increased surface roughness of the surface with respect tothe flat substrate and to the micro-nanocapillarity effect of TiO2NRs. The direct implementation of such structures into microfluidicdevices is demonstrated.

9:00 AMElectron Beam Induced Fabrication of Nanodendritic Tree-structures on Insulator SubstratesK. Furuya*, M. Song, K. Mitsuishi, National Institute for MaterialsScience, Japan

The reaction of gas molecules with electrons near materials surfacesometimes causes the solid deposit, which has a variety in size andshape depending on the substrate materials and the profile of elec-trons. Once gases containing W and Pt are introduced in a TEM,metal nanostructures can be fabricated in-situ. When insulator wasused as a substrate, inhomogeneous deposition occurs due to thecharge-up electrons and forms nanodendritic tree-structures. Atabout 0.75 A/cm2 with the flow of W(CO)6 gas, the deposits grewself-standing, separated each other and perpendicular to surface. Thelength is several ten nanometers. Branches are observed at the tipwhere the thickness is about 3 nm. It becomes a fractal-like tree struc-ture grown to 100 to 300 nm in length at about 17.9 A/cm2. These W-nanodendrites can be used for catalysis studies in combination withion sputtering method to form a compound metal-nanoparticles/W-nanodendrite structure.

9:20 AMHydrothermal Production and Characterization of StructuresGrown on Titanium MetalJ. D. Sorge*, D. P. Birnie, Rutgers University, USA

The hydrothermal growth of titanium-based nanostructures on tita-nium metal creates a thick film that may have properties, such as en-hanced conductivity and fewer defect sites, that are conducive to in-creased efficiency in dye sensitized solar cells. However, the growthmechanism of the structures and their composition variability withprocessing parameters is not well understood. In this research, thecomposition and morphology are characterized with respect to thegrowth conditions using transmission electron microscopy amongother methods. This leads us to better understand the mechanisms ofgrowth in a basic solution at low temperatures, less than 175°C, anduse these titania layers for eventual incorporation into the productionof dye sensitized solar cells.

10:00 AMProperties of Alumina Dielectrics via Ink Jet ProcessE. Koo*, J. Kim, Korea institute of Ceramic Engineering & Technology,South Korea

Low loss dielectrics below 10 μm have been fabricated on Si wafer viaink jet process. Alumina suspensions as a dielectric ink were formu-lated with alumina powder and an anionic polymer dispersants informamide/water. Alumina powders of the size of 0.2, 0.3, and 0.54μm were used, respectively. The microstructure was investigated byfield emission scanning electron microscope (FE-SEM). We also cal-culated the alumina packing density of dielectric layer using 0.2, 0.3,and 0.54 μm alumina inks. The volume fraction of alumina of the di-electric layer by ink-jet process is about 65% much higher than thatof the dielectric of around 40% fabricated by a conventional wet cast-ing method. Furthermore, the permittivity and Q factor of the dielec-tric were evaluated by impedance analyzer. The results suggest thatthe dielectrics with high Q value and dimensional stability can beused for high speed electronic applications.

10:20 AMInkjet printing of nanocrystalline titania layers for dye sensitizedsolar cellsS. Phadke*, A. Jackson, D. P. Birnie,III, Rutgers University, USA

Drop-on-demand inkjet printing allows precise control of film depo-sition parameters enabling this technique to be used for combinator-ial study of thin film systems.We demonstrate inkjet printing ofanatase titania nanoparticle thin films for making the dye sensitizedsolar cells.The main challenge is to obtain an ink formulation withsuitable surface tension and viscosity so that optimal ink droplets areformed.Boiling point elevation of the ink and modification of surfaceenergy of the substrate are taken into account to obtain uniform,continuous film with no coffee ring effect.We also control jettingwaveform, firing voltage and drop spacing parameters to optimize thetitania film uniformity. Effect of these deposition parameters on themicrostructure of the film is studied using optical and electron mi-croscopy.Libraries of titania films are built with varying number ofinkjet printed layers and titania loading which can then be used tocompare the performance of dye sensitized solar cells.

10:40 AMProcessing of Electrospun Ceramic Nanoparticles and Fibers(Invited)W. M. Sigmund*, University of Florida, USA

Electrospinning and electrospraying are exciting novel approaches inthe field of ceramics to synthesize a variety of nanostructures, be itnanoparticles, nanotubes, nanofibers, ribbons, or ceramic fiber mats.They appear to be amongst the most versatile processing strategies toachieve nanostructures under ambient conditions for many ceramics.This talk will present a short overview of electrospraying and spin-ning with focus in recent advances. Furthermore, the processing ofthese materials will be discussed for fabrication of novel sensors,novel filters and more.

11:20 AMFormation of Composite Electrodeposited Ni-WC CoatingsR. K. Saha*, T. Khan, University of Calgary, Canada

Electrodeposition is one of the most important techniques for pro-ducing nano-composite coatings, owing to the advantages includingprecisely controlled near room temperature operation, low energy re-quirements, capability to handle complex geometries, and low cost.In this study, electrodeposition techniques are used to develop Nicoatings reinforced with hard nano-sized (~20nm) dispersion oftungsten-carbide particles and the research investigates the effect ofcoating parameters i.e., the particle content and the current densityon the morphology of the deposition. The effects of post-depositionheat treatment on the hardness of the coatings are studied. The mi-crostructural features of the coatings are characterized by scanningelectron microscopy. Vicker’s micro-hardness tests are conducted tomeasure the hardness of the composite coatings. The results showthat the use of proper process parameters is crucial to achieve dense,defect free coatings containing a uniform distribution of tungsten-carbide particles.

11:40 AMOrientation Effect on Stiffness of Layer-by-Layer AssembledNano-Composite FilmsL. Sui*, N. A. Kotov, J. Kieffer, University of Michigan, USA

Multilayered films composed of cellulose nanocrystals (cellN) andpoly(diallyldimethylammonium chloride) (PDDA) were fabricatedusing layer-by-layer (LBL) assembly. Cellulose nanocrystals of 200 –400 nm and > 1 μm in lengths were aligned via shear flow to createdLBL films with oriented fiberils. The composite films’ elastic moduliwere studied using Brillouin light scattering (BLS) as a function ofthe degree of fiber alignment. BLS allows for non-invasive determina-tion of elastic constants at the nanoscale and for various orientations,

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 193

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania194

including in-plane, i.e., parallel to the fiber alignment (c11) and per-pendicular to it (c22), and in growth direction (c33). c11 exceeds c22 byup to a factor of two, more so the longer cellNs. The ratio between c33and in-plan moduli, which also varies significantly depending on thegrowth conditions, provides information about the adhesion and thedegree of interpenetration of fibers between layers.

12:00 PMNanostructured TiN/CNx Multilayer FilmsA. Vyas*, The Hong Kong Polytechnic University, China; K. Li, Y. Shen, CityUniversity of Hong Kong, China

Nanostructured TiN/CNx multilayer films were deposited ontoSi(100) and M42 high-speed-steel substrates. The bilayer thickness(with TiN layer fixed at 3.0 nm while the CNx layer thickness was var-ied from 0.3 to 1.2 nm) significantly affected the mechanical and tri-bological properties of TiN/CNx multilayer films. The chemicalstates, TiN, TiC, TiNxOy and TiO2, existed in a TiN layer. A maxi-mum hardness of ~41.0 GPa was observed in a film with TiN=3.0 nmand CNx=0.9 nm. All multilayer exhibited extreme elasticity withelastic recoveries as high as 80% at 5 mN maximum load. The com-pressive stresses was in a range of 1.5–3.0 GPa. The friction coefficientvalue for a multilayer (TiN=3.0 nm and CNx=0.9) nm was measuredto be in 0.11 and the specific wear rates of the order x 10-16. Byscratch and Rockwell-C adhesion tests, films with smaller bilayerthicknesses (TiN=3.0 nm, CNx=0.3 and 0.6 nm) exhibited the bestadhesion and cohesive strength. The critical load value obtained wasas high as ~78 N.

Nanotechnology: Nano-Materials forElectronic & Multifunctional Applications

Nanotubes, Nanorods and NanowiresRoom: 409Session Chair: Siu-Wai Chan, Columbia University

8:00 AMAdvances in Synthesis and Application of Carbon NanotubeMaterials (Invited)V. Shanov*, Y. Yun, M. Schulz, University of Cincinnati, USA

This talk will focus on the latest results in catalytic synthesis of cen-timeter long CNT arrays by CVD. The role of the catalyst design onthe substrate and its impact on the length of the oriented CNT will berevealed. Additionally, characterization of the arrays by ESEM,HRTEM, Raman Spectroscopy, and TGA will be discussed. The talkwill also illustrate exiting applications of the CNT arrays related totheir unique properties. Recent advances in the development of“Black Cotton™”, which is centimeter long CNT arrays grown onlarge substrates, will be presented. Applications of nanotechnologyunder development in our lab include spinning Black Cotton intothread to produce a new smart material with reinforcement, sensing,and actuation properties and use of CNT arrays for electrode andbiosensor development. The talk will also present current research ef-forts to scale up the cultivated process, and to develop the manufac-turing tools and methods that industry needs to “mass produce”aligned CNT.

8:40 AMProduction of nano silicon carbide rods by high temperature arcplasma heating of silicon carbide grainsB. B. Nayak*, S. K. Pradhan, B. K. Mishra, IMMT, India

The objective of this study is to develop a suitable process for growingsilicon carbide nano rods which have good applications in atomicforce microscopy, data recording,nano composites etc. Silicon carbidegrains taken in a graphite crucible were heat treated above 2800 K inargon and/or hydrogen atmosphere by employing an arc plasma.Byoptimizing process conditions, silicon carbide nano rods were grown

on the carbide grain surfaces and results are quite reproducible.HRTEM, AFM and SAD extablished the micro structure, phase andorientation of the nano rods (002 & 101) thus grown.Micro Ramanspectra of the nano rods confirmed the constituent to be silicon car-bide which got refined by introduction of hydrogen at the heat tret-ment stage.The results establish a plasma process for production ofsilicon carbide nano rods. B.B.Nayak, S.K.Pradhan and B.K.MishraInstitute of Minerals and Materials Technology Bhubaneswar-751013, India Key words: nano rods, SiC

9:00 AMGrowth of Carbon Nanotubes on Porous Microcellular CarbonSubstratesI. T. Barney*, S. M. Mukhopadhyay, A. G. Jackson, Wright State University, USA

This project focuses on the growth of carbon nanotubes (CNT) overlarger structures, including microcellular porous materials. The goalis to create multi-scale materials with increased surface area for ad-vanced thermal, catalytic and electrochemical applications. CNT havebeen fabricated on various graphitic substrates (carbon foams, fibersand model surfaces) using chemical vapor deposition (CVD). Struc-ture and morphology of CNT growth has been characterized usingFESEM and analyses of chemical states have been preformed using x-ray photoelectron spectroscopy (XPS) It is seen that a plasma en-hanced nanocoating on the uneven surface enhances its catalytic ac-tivity, and improves CNT growth. Other factors influencing growthkinetics are gas flow and pore geometry. BET surface area analysis andthermal transport measurements have been performed to understandstructure-property relationships. These results will be presented inlight of understanding and controlling growth mechanisms for futureapplications.

9:20 AMCeramic Nano-structures without Lithography (Invited)S. A. Akbar*, Ohio State University, USA

Recent work in the author’s laboratory has led to the development ofsurface modification techniques for the fabrication of nanostructuresthat are inexpensive, highly scalable and do not require use of lithog-raphy. One such process creates nanofiber arrays of single crystalTiO2 oriented along the <001> direction by gas phase etching in aH2/N2 environment. Our work on single crystal TiO2 shows that onAu-catalyzed (001) surface, oriented nano-fibers can be grown with<001> and <110> alignments using H2/N2 heat treatment. We havealso developed a process to create nanofibers of TiO2 on Ti64 alloysvia oxidation under a limited supply of oxygen. Recently, a high tem-perature anneal of a GDC film on a YSZ single crystal created a peri-odic array of single crystal nano-islands with regular size, shape, anddistance from their nearest neighbors. These nano-structures can beused as platforms for chemical sensing, photocatalysis and biomed-ical applications.

10:00 AMSynthesis, Characterization, and Properties of Metal-Oxide-MetalHeterojunction NanowiresE. D. Herderick*, N. P. Padture, The Ohio State University, USA

Oxide nanowires are being used increasingly as 1-dimensional (1-D)building blocks in “bottom up” multifunctional nanoelectronics,taking advantage of the myriad size-dependent functional propertiesof oxides. In this context, metal—oxide—metal (MOM) heterojunc-tion nanowires, where a nanoscale segment of a functional oxide issandwiched axially between two noble-metal nanowires, are likely tohave some distinct advantages over all-oxide nanowires (where theentire nanowire is an oxide), including definition of the functionalsegment of oxide and “end-on” contacts. In order to study piezoelec-tric and ferroelectric properties of nanoscale oxides, a novel synthe-sis method is developed to make MOM nanowires in the Au-BaTiO3-Au system. The synthesis method is described in detailalong with characterization results of the MOM nanowire structure.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 194

Wed

nes

day

AM

www.matscitech.org 195

Additionally, an approach for fabricating electronic devices incorpo-rating these nanowires, and subsequent property measurements arepresented.

Nanoscale Films and CoatingsRoom: 409Session Chair: Siu-Wai Chan, Columbia University

10:20 AMNovel 3-D Micro/Nanostructured Sn/SnO2 FilmsY. Sun*, University of South Carolina, USA; J. Liang, EMC Corp., USA; X. Li,University of South Carolina, USA

Both Sn and SnO2 are attractive materials, being intensively studiedfor applications in Li-ion battery anodes, gas sensors and otherphotoelectrochemical applications. A novel 3-D micro/nanostruc-tured Sn film was deposited using a simple one-step electrodeposi-tion technique. The architecture includes hollow tubes (with tubethickness in the range of ~100-200nm) with secondary axialgrowth of nanowire “arms”. The effect of the deposition parame-ters, e.g. pH, current density, etc. on the resultant morphology wasanalyzed. EDX and HRTEM were used to study the texture and ori-entation of both the tube wall and the secondary arms. Nanoinden-tation is performed on a single tube to probe its mechanical prop-erties. The original structure is transformed into SnO2 film bythermal oxidation while maintaining the unique morphology. Thenthe gas sensing and photoelectrochemical properties of the filmswere characterized.

10:40 AMAtomic Layer Deposition of ceramic films on particles using afluidized bed reactorD. M. King*, X. Liang, A. W. Weimer, University of Colorado, USA

Atomic layer deposition (ALD) was used to deposit ceramic films ona variety of particle types in a fluidized bed reactor. Both metal ox-ides and metal nitrides were deposited on primary nano- and mi-cron-sized powders for the development of advanced nanocompositematerials with enhanced optical, electrical or mechanical properties.The sintering of nanocomposite powders fabricated using ALD pro-vided a more homogeneous distribution of the core and shell mate-rials, relative to a standard solid state reaction between twonanopowders. Grain growth was significantly inhibited due to thenanothick capping films, which were conformal and pinhole-free.Particle ALD is a superior method to introduce and evenly distributelow weight percentages of dopant materials into nanocompositestructures.

11:00 AMImproved Electronics Reliability for Thin Film Smart MaterialsWhen Exposed to Severe Longitudinal VibrationsW. D. Nothwang*, M. Cole, D. Demaree, S. Hirsh, C. Hubbard, E. Ngo, U.S.Army Research Laboratory, USA

For many applications, sensors and electronic components are ex-tremely susceptible to longitudinal waves, which are a primarysource of device failure. To mitigate electronics’ susceptibility tothese waves, alternative adhesion mechanisms are addressed, andpreferred materials stacking is designed. Ferroelectric thin films ofBa80Sr20TiO3 were successfully deposited by metal-organic solu-tion deposition with a nominal film thickness of 200nm, and wereintegrated onto silicon and alternative substrates. The films werefully crystallized after annealing with dense, crack and pinhole freesurfaces, with an average surface roughness between 7.0 nm and10 nm for the crystallized films. The materials dispersion coeffi-cient and the material stiffness were measured, and the structureswere effective at decreasing the susceptibility to longitudinal en-ergy waves.

11:20 AMStructural, Mechanical and Tribological Properties ofNanocrystalline Diamond FilmsH. Gomez*, H. Jeedigunta, A. Kumar, University of South Florida, USA

The interest of diamond films is based on the unique properties thatcan be achieved using this material in particular applications, includ-ing new thin film technology and nanomaterial science. Synthesis ofdiamond thin films has a high potential for many industrial applica-tions due the outstanding properties in diamond-coated products.Diamond films with smaller grain size, often referred to as “nanocrys-talline diamond”, has a smooth surface, more grain boundaries andless highly oriented grains. Intrinsic and extrinsic nanocrystalline di-amond films were grown for silicon substrates by microwave plasmachemical vapor deposition using different CH4/Ar/H2 gas chemistries,substrate temperatures, pressures and M. W. power. Correlations be-tween process parameters and properties of the films were establishedby atomic force microscopy, scanning electron microscopy, Ramanspectroscopy, near-edge X-ray absorption fine structure, nanoinden-tation, pin on a disk and four point delamination tests.

Processing & Product Manufacturing:International Symposium on Ceramic MatrixComposites

Ceramic Fiber CompositesRoom: 413Session Chair: Raj Singh, University of Cincinnati

8:00 AMRecent Research Trends of Advanced Fiber-Reinforced CeramicMatrix Composites in Japan (Invited)Y. Kagawa*, The university of Tokyo, Japan

Ceramics fiber-reinforced ceramic matrix composites have beenknown as highly damage tolerant over monolithic ceramics. Japan hasbeen developed SiC and Al2O3 fibers and some applications usinglarge damage tolerant behavior are recently available. The research anddevelopment trends in Japan will be presented. The presentation con-tains: (i) SiC fiber-SiC matrix, Carbon fiber-SiC matrix compositesand their research trends, (ii) fiber-reinforced and monolithic hybridceramic matrix composites and (iii) new ZrB2 matrix ultra-high tem-perature ceramic composites. In addition, resent research results of X-ray and electromagnetic wave techniques for NDE of fiber-reinforcedceramic composites, which developed my laboratory, will be presented.

8:40 AMProcessing and High Temperature Mechanical Properties of Si/SiCComposites Fabricated by Melt Infiltration (Invited)R. N. Singh*, University of Cincinnati, USA

Melt-infiltration is a promising technique for fabricating fully denseand net-shape SiC fiber-reinforced Si-SiC composites. The high tem-perature mechanical properties of these composites may be limited bythe properties of the fiber and Si-SiC matrix. In particular, the matrixproperties depend on the amount of Si in the Si-SiC matrix phase.Therefore, Si-SiC composites containing 10-45 vol% Si were fabri-cated using melt-infiltration process and their microstructure andmechanical properties were measure between 1250-1550°C. Elasticmodulus, strength, and creep behaviors were studied. The influenceof the Si content on these properties will be presented and discussed.

9:20 AMEffects of Environment on Creep Behavior of Nextel720™/Alumina-Mullite Ceramic Composite at 1200 °°CM. Ruggles-Wrenn*, C. Genelin, Air Force Institute of Technology, USA

The tensile creep behavior of an oxide-oxide continuous fiber ce-ramic composite was investigated at 1200 °C in laboratory air and in

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 195

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania196

steam. The composite consists of a porous alumina-mullite matrixreinforced with laminated, woven mullite/alumina (Nextel™720)fibers, has no interface between the fiber and matrix, and relies on theporous matrix for flaw tolerance. The tensile stress-strain behaviorwas investigated and the tensile properties measured at 1200 °C. Theelastic modulus was 74.5 GPa and the ultimate tensile strength was153 MPa. Tensile creep behavior was examined for creep stresses inthe 70-140 MPa range. Primary and secondary creep regimes wereobserved in all tests. Creep run-out (set to 100 h) was achieved in lab-oratory air for creep stress levels ≤ 90 MPa. The presence of steam ac-celerated creep rates and reduced creep lifetimes. Composite mi-crostructure, as well as damage and failure mechanisms wereinvestigated.

10:00 AMMicrostructural Concepts for Robust Oxide Composites (Invited)F. Zok*, University of California, Santa Barbara, USA

Current generations of continuous fiber ceramic composites(CFCCs) exhibit two performance limitations. (i) In the absence of afiber coating, retention of matrix porosity during long-term high-temperature exposure is critical to maintaining damage tolerance. (ii)With two-dimensional fiber architectures, CFCCs are vulnerable todelamination under application of moderate out-of-plane stress, es-pecially in composites with porous matrices. The present paper willfocus on strategies to address these deficiencies. These include the useof very thin (<10 nm) fugitive coatings to decouple the fibers fromthe matrix as well as the use of 3D reinforcement topologies. Imple-mentation challenges of the latter strategy are addressed through theuse of multimodal particle size distributions (to mitigate dryingcracks) as well as a vibration-assisted route for slurry infiltration. Acritical assessment of the ensuing benefits will be made through com-parisons of the mechanical properties of these systems with conven-tional CFCCs.

10:40 AMDistinguished Functions Making the Best Use of the UniqueComposite Structures (Invited)T. Ishikawa*, Ube Industries, Ltd., Japan

We developed lots of thermo-structural ceramics composed ofunique composite structures. Using the base-technologies, we alsodeveloped numerous functional ceramics, which can be used in thewide field. The first one is a tough, thermo-structural ceramic (SA-Tyrannohex), which consists of a highly ordered, close-packed struc-ture of hexagonal columnar SiC-polycrystalline-fibers with a verythin interfacial carbon layer between fibers. The second one is astrong photocatalytic fiber produced from the same raw material forpreparing the SA-Tyrannohex, which can be used in a water-purifier.The third one is a durable, ultraluminous structure for incandescent,high-power white-LED, which consists of binary single crystals en-tangled with each other continuously. This ceramic was initially de-veloped as an excellent thermo-structural ceramic which can with-stand up to 1700 degree C in air. In my presentation, our strategyconcerning the development of unique functional ceramics will bealso appeared.

11:20 AMForeign Object Damage Behavior in Ceramic Matrix Composite atAmbient TemperatureS. R. Choi, D. Alexander*, Naval Air Systems Command, USA

Foreign object damage (FOD) behavior of an oxide/oxide (N720/AS)ceramic matrix composite (CMC) was determined at ambient tem-perature using impact velocities ranging from 100 to 400 m/s by 1.59-mm diameter steel-ball projectiles. The degree of post-impactstrength degradation increased with increasing impact velocity, andwas greater in a partially supported configuration than in a fully sup-ported one. For the fully supported configuration, frontal contactstress played a major role in generating composite damage, while for

the partially supported case both frontal contact and backside tensilestresses were the combined sources of damage generation. The mate-rial beneath impact site was compacted due to the porous nature ofthe material. The oxide/oxide composite was able to survive high en-ergy (<1.3 J) impacts without complete structural failure. A model topredict impact force in partial support was made and assessed withthe experimental data.

Processing & Product Manufacturing: Joiningof Advanced and Specialty Materials X

Joining of CeramicsRoom: 410Session Chair: Michael Halbig, NASA Glenn Research Center

8:00 AMThe sources of flaws in air brazed jointsJ. Darsell*, K. Weil, Pacific Northwest National Laboratory, USA

Air brazing is a joining method that is under investigation for sealingSolid Oxide Fuel Cells (SOFCs). This method uses an oxide com-pound dissolved in a molten noble metal solvent, in this case CuO inAg, such that ready wetting occurs on a number of oxide substrates.For SOFC use, it is critical that the resulting seal maintains hermitic-ity and mechanical strength. Flaws such as heterogeneities and poros-ity contribute to leaking and failure in the seal. Thermodynamicallyinduced flaws have been observed to form during heating by opticalobservations through a transparent oxide substrate. This presentationwill discuss the sources of theses flaws in the Ag-CuO air braze fillermetal and the means to prevent them.

8:20 AMMechanical strength of air brazed jointsJ. Darsell*, K. Weil, Pacific Northwest National Laboratory, USA

Air brazing is under consideration for joining metals and ceramicmaterials for use in high temperature devices such as Solid OxideFuel Cells (SOFC) and gas separators. In this work the mechanicalstrength of joint made with air brazes will be presented. Joint wereprepared by joining yttria-stabilized zirconia, a typical SOFC elec-trolyte material, using air brazes and tested in four-point bend. Aftertesting the fracture surfaces were examined using scanning electronmicroscopy (SEM) and energy dispersive spectroscopy using x-rays(EDS-X). We will present our latest findings and discuss the implica-tions in terms of using the method of sealing for high temperatureelectrochemical devices.

8:40 AMAtomic Structure of Molten Ag-CuO Air Brazing Filler AlloysJ. S. Hardy*, J. Y. Kim, L. R. Pederson, PNNL, USA; M. J. Kramer, AmesLaboratory, USA; R. Weber, Materials Development, Inc, USA; C. J. Benmore,Argonne National Laboratory, USA; S. Weil, PNNL, USA

Using a process known as air brazing, ceramic-ceramic and ceramic-metal joining can be accomplished using Ag-CuO based filler alloyswhich are fired in air to create brazed joints. This technique elimi-nates the need for maintaining the vacuum, inert, or reducing atmos-phere that is required during firing in most other brazing techniques.The Ag-CuO family of alloys is somewhat unique in that the phase di-agram shows appreciable levels of mutual solubility between an oxideand a metal in the liquid state. Alloys containing less than 30 – 40mol% Ag form a Cu-rich liquid when molten. Meanwhile, alloys con-taining more than 97-99 mol% form a Ag-rich liquid when molten.Alloys containing concentrations of Ag falling between these levelsform an immiscible liquid containing both phases. The atomic struc-ture of selected Ag-CuO alloy compositions in each of these composi-tional regions including the pure Ag and CuO end members weremeasured in the molten state in air using high energy x-ray scattering.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 196

Wed

nes

day

AM

www.matscitech.org 197

9:00 AMLarge area joining of Sialon to Steel by reactive brazingS. Boddapati*, D. R. Siddle, S. Brahmandam, I. Spitsberg, Kennametal, Inc, USA

Joining ceramics to steels is technologically challenging due to signif-icant difference in their thermomechanical properties such as ther-mal expansion coefficient and Young’s modulus, which result in highresidual stresses often leading to failure of ceramic during joining.Most of the ceramic/metal joining studies so far have been confinedto small joining areas (~ 1 cm2). However, many engineering applica-tions require joining areas larger than 6.25 cm2 or 1 in2. Therefore,the focus of this work is on large area joining of Sialons to H13 steelbecause of practical importance. Both finite element modeling andexperiments have been used to understand the issue of thermal resid-ual stresses and the effect of process parameters. Shear strengthsachieved are comparable to what has been achieved on smaller sam-ples (< 5 cm2 area). A main issue in testing Sialon/H13 joints was thepresence of bending load in addition to the shear load. The methodsemployed to standardize the test method will also be described.

9:20 AMEffect of Pressure on Air Brazed Alumina JointsA. Ibrahim*, F. Ul Hasan, University of Engg and tech , Pakistan

Joining of ceramic to similar and/or dissimilar materials throughbrazing is being widely studied to bring together beneficial propertiesof different base materials. In addition to the compatibility betweenthe interlayer and the base material, the mechanical properties of thejoint are governed by brazing conditions. In this study alumina blockshave been joined with thin aluminium interlayer in air and the effectof varying joining pressure, holding time and temperature on thestrength and microstructure has been investigated. It has been foundthat application of pressure under atmospheric condition yieldsjoints with better or comparable bond strength at relatively lowerbrazing temperatures and also in reduced processing time.

10:00 AMJoining of Silicon Carbide: Diffusion Bond Optimization andCharacterizationM. Halbig*, M. Singh, Army Research Laboratory, USA

Joining and integration methods are critically needed as enablingtechnologies for the full utilization of advanced ceramic componentsin aerospace and aeronautics applications. One such application is alean direct injector for a turbine engine to achieve low NOx emis-sions. In the application, several SiC substrates with different holepatterns to form fuel and combustion air channels are bonded toform the injector. Diffusion bonding is a joining approach that offersuniform bonds with high temperature capability, chemical stability,and high strength. Diffusion bonding was investigated with the aid oftitanium foils and coatings as the interlayer between SiC substrates toaid bonding. The influence of such variables as interlayer type, inter-layer thickness, substrate finish, and processing time were investi-gated. Optical microscopy, scanning electron microscopy, and elec-tron microprobe analysis were used to characterize the bonds and toidentify the reaction formed phases.

10:20 AMActive Metal Brazing and Characterization of Brazed Joints in C-Cand C-SiC Composites to Cu-clad-Molybdenum SystemM. Singh*, Ohio Aerospace Institute, USA; R. Asthana, University ofWisconsin-Stout , USA

C/C composites with CVI and resin-derived matrices, and C/SiCcomposites with T-300 carbon fibers in a CVI SiC matrix were joinedto Cu-clad Mo using two Ag-Cu braze alloys, Cusil-ABA (1.75% Ti)and Ticusil (4.5% Ti). The brazed joints revealed good bonding, pref-erential precipitation of Ti at the composite/braze interface, and atendency toward delamination in resin-derived C/C composite. Ex-tensive braze penetration of the inter-fiber channels in the CVI C/C

composites was observed. The Knoop microhardness (HK) distribu-tion across the C/C joints indicated sharp gradients at the interface,and a higher hardness in Ticusil than in Cusil-ABA. For the C/SiCcomposite to Cu-clad-Mo joints, the effect of composite surfacepreparation revealed that ground samples did not crack whereas un-ground samples cracked. Theoretical predictions of the effective ther-mal resistance suggest that such joined systems may be promising forthermal management applications.

10:40 AMJoining of Zirconium Diboride-Based Ceramic Composites toMetallic Systems for High-Temperature ApplicationsR. Asthana*, University of Wisconsin-Stout, USA; M. Singh, Ohio AerospaceInstitute, USA

Three types of hot-pressed ZrB2-based ultra-high-temperature ceramiccomposites, ZrB2-SiC, ZrB2-SiC-C, and ZrB2-SCS9-SiC, were joined toCu-clad-Mo using two Ag-Cu brazes (Cusil-ABA and Ticusil, TL~1073-1173 K) and two Pd-base brazes (Palco and Palni, TL~1493-1513 K).Scanning Electron Microscopy coupled with EDS revealed greater chem-ical interaction in joints made using Pd-base brazes than in joints madeusing Ag-Cu based active brazes. The degree of densification achieved inhot pressed composites influenced the Knoop hardness of the UHTCCand the hardness distribution across the braze interlayer.The braze regionin Pd-base system displayed higher hardness in joints made using fully-dense ZS composites than in joints made using partially-dense ZSS com-posites and the carbon-containing ZSC composites. Empirical projec-tions show a reduction in the effective thermal resistance of the joints andhighlight the potential benefits of joining the UHTCC to Cu-clad-Mo.

Processing & Product Manufacturing:Processing, Properties and Performance ofComposite Materials

Properties of Composite MaterialsRoom: 412Session Chairs: Amit Misra, Los Alamos National Laboratory; TroyTopping, University of California, Davis

8:00 AMThermal Transport in Composite Materials and Its Interfaces(Invited)A. Roy*, Air Force Research Laboratory, USA

Aircrafts use its fuel as its primary heat sink in managing thermalload. The thermal loads have steadily increased to the upper temper-ature limit of the electronics in numerous operations scenarios; thuslimiting the system performance, such as of F-22 and F-35 aircrafts.The thermal management issues for high energy laser (HEL) systemshave become even more challenging. The thermal transport in het-erogeneous materials systems, such as composites, is essentially con-trolled by the phonon scattering phenomena at the materials inter-faces due to materials property mismatch. Such phenomena are alsoprevalent in joints or component interfaces. In this presentation, themechanism of thermal transport in aerospace composite in molecu-lar to macroscopic scale will be discussed. In addition, a thermal in-terface concept, incorporating aligned MWCNT, to enhance through-thickness thermal conductivity in adhesive joints, will be presented.

8:40 AMInvestigation of Absorptivity for Fiber Laser Assisted Machiningof Silicon NitrideF. Sciammarella, S. Panguntani*, Northern Illinois University, USA

A lot of work has been carried out in the field of Laser Assisted Ma-chining (LAM) of ceramics. Most of this work was done with tradi-tional lasers (CO2, Nd:YAG) and has shown promise. With the adventof the fiber lasers, using this technology for industrial applicationshas made it more feasible. Currently there are no standards available

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 197

Wed

nesd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania198

that provide information on how much energy is needed to generatethe transformation of bulk ceramic material into the required glassyphase for machining. This type of information is critical for the de-velopment of industrial equipment to perform in optimal conditions(minimizing amount of energy required for given conditions).Therefore this investigation will build from past work and generate adatabase of parameters and outcomes using fiber lasers on Si3Ni4.The goal is to provide useful information to build and evaluate futuresystems for laser assisted machining of any type of hard material.

9:00 AMFracture and Fatigue of Implantable CablesJ. Lewandowski*, R. Varadarajan, B. Smith, Case Western ReserveUniversity, USA

The mechanical behavior of a variety of cable architectures comprised ofsilver-cored composite wires were evaluated in uniaxial tension, and incyclic strain-controlled fatigue with the use of a Flex tester operated toprovide fully reversed bending fatigue. The magnitude of cyclic strainsimparted to each cable tested was controlled via the use of different di-ameter mandrels. Smaller diameter mandrels produced higher values ofcyclic strain and lower fatigue life. Multiple samples were tested and ana-lyzed via scanning electron microscopy. The fatigue results were analyzedvia a Coffin-Manson-Basquin approach and compared to fatigue dataobtained on 316LVM cables where testing was conducted in an identicalmanner. The effects of changes in wire diameter, cable architecture, andwire composition (i.e. silver-cored composite vs 316 LVM) are discussed.

9:20 AMAging of Mechanically Alloyed Cu2Fe4W4A. O. Aning*, A. Rojas, N. Monsegue, Virginia Tech, USA

Elemental powders of Cu, Fe, and W were milled for 10 hours in aSPEX mill to form a near supersaturated solution of stoichiometricCu2Fe4W4. Age hardening treatments of the powders were performedat 800oC, 1000oC and 1100oC. Optical microscopy showed that Cu-rich precipitates evolved and coarsened with time. Micro-hardnessvalues were as high as 1500 VH, for the sample annealed at 800oC for5 hours. There were almost no cracks as a result the hardness testing,indicating the aged alloys are hard and tough. Microstructural evolu-tion and corresponding sample hardness will be discussed.

10:00 AMSliding Wear and Damping Characteristics of Fly ash reinforcedA356 Al Matrix CompositesM. K. Surappa*, S. Sarappa, Indian Institute of Science, India

Sliding wear characteristics of 6 and 12 vol.% fly ash reinforced A356Al alloy composites have been studied on pin-on-disc machine. Testswere done with loads of 10, 20, 50, 65 and 80 N at a constant slidingvelocity of 1m /sec. Composites were made by stir cast route and sub-sequently hot extruded. Results show that the dry sliding resistance ofAl-fly ash composite is similar to that of Al2O3 or SiC reinforced alu-minum alloy. Composites exhibit improved wear resistance comparedto unreinforced alloy up to a load of 80 N. Particle size and volumefraction of fly ash particle significantly affect the sliding wear andfraction characteristics of composites. At high loads (>50N), wherefly ash particles act as load bearing constituents, the wear resistance ofA356 Al alloy reinforced with narrow size range (53-106μm) fly ashparticles were superior to that of the composite having the same vol-ume fraction of particles in the wide range (0.5-400μm).

10:20 AMImproving the transverse tensile strength of power metallurgy Al-Y-Ni-Co alloy through the introduction of SiC particles intomonolithic alloyY. Wang*, R. S. Mishra, Missouri University of Science & Technology, USA; T.J. Watson, Pratt & Whitney, USA

For advanced Al-RE-TM alloys produced by the consolidation ofamorphous powders, the transverse tensile strength is often relatively

lower compared to the longitudinal direction, due to the presence ofprior particle boundaries (PPBs) oriented parallel to the longitudinaldirection. In this paper, tensile properties of unreinforced base alloyand reinforced Al-Y-Ni-Co alloy matrix composite will be presented.The results show that the addition of SiC particles into the Al-Y-Ni-Co alloy significantly improve the transverse tensile strength com-pared to unreinforced alloy. This improvement is attributed to thebreaking up of PPBs by angular SiC particles during the consolidationand hot extrusion processing. Through secondary thermomechanicalprocessing, the transverse ductility of the composite can be improvedto ~5% due to the homogenized SiC particle distribution.(Approvedby DARPA for Public Release, Distribution Unlimited).

10:40 AMMechanical Properties of TiB/Ti-6Al-4V Metal Metrix CompositePrepared by Spark Plasma SinteringH. Izui*, Nihon University, Japan

In-situ TiB whisker reinforced Ti-6Al-4V metal matrix compositeshave been fabricated by spark plasma sintering (SPS). This study wasundertaken to investigate the effect of sintering conditions and TiBvolume fraction on the mechanical properties and microstructures ofthe composites: (1) Tensile strength in the room temperature to 700°C; (2) Fatigue resistance at 600 °C ; (3) Creep rupture strength at 600°C; (4) Elastic modulus; (5) Coefficent of thermal expansion. Thetensile properties of the composites with lower TiB volume fractionby SPS show higher than those of the composites by mechanical al-loying and HIP. The microstructures were also evaluated.

11:00 AMDamage Fractography of C/C-SiC Composite at ElevatedTemperature under LoadsV. K. Srivastava*, S. Singh, Institute of Technology, India

Ceramic matrix composites are the promising materials for high tem-perature application because of their low density, high strength, hightoughness and high durability at elevated temperatures. Carbon-car-bon-silicon carbide (C/C-SiC) composite is one of the structural ma-terials, which comprises all the above properties at high tempera-tures. The main objective of present study was to characterize theeffects of high temperature in open atmosphere on the stress rupturebehaviour of C/C-SiC composite. For this purpose, tensile and com-pressive stress rupture tests were conducted on oxidized C/C-SiCcomposites at temperature, 900oC with the variation of exposuretime. Finally, Scanning Electron Microscopy (SEM) test was used toevaluate the morphology of fractured and compressed samples. It wasa practical and useful way to find out the behaviour of damage mor-phology of fibre and matrix.

Keynote & Lectures

Robert B. Sosman LectureRoom: 406

1:00 PMInterfacial Kinetic Engineering: How Far Have We Come SinceKingery’s Inaugural Sosman Address? (Invited)M. P. Harmer*, Lehigh University, USA

The manipulation of the rate of atomic transport along and acrossinterfaces (most notably grain boundaries) remains a centraltheme in the control of the microstructure and properties of inor-ganic materials. This is described as the field of interfacial kineticengineering of materials. In his opening Sosman Memorial lecturein 1973, Professor Kingery proposed a set of plausible conceptswhich he considered to be necessary and sufficient for the inter-pretation of ceramic grain-boundary phenomena, which providedan early foundation for conducting interfacial kinetic engineer-ing. This 2008 Sosman Memorial lecture will attempt to provide

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 198

Wed

nes

day

PM

www.matscitech.org 199

both a retrospective assessment and a prospective viewpoint ofthis persistently challenging field of study. A noteworthy new con-cept that has emerged is that of grain boundary complexions,which is considered to have important implications to the field ofkinetic engineering in a wide variety of both ceramic and metalsystems.

Special Topics: Industry Track 2008

Industry Track 2008, Wednesday PMRoom: Hall A

2:00 PMRoll Failure Analysis, Causes and Prevention (Invited)J. Sychterz*, Union Electric Steel, USA

Metal rolling operations can encounter roll failures (roll marks,cracks, spalling, breakage) that affect mill productivity and can in cer-tain cases be a safety concern. The purpose of this presentation is todiscuss: Roll Failure Mechanisms, Preventive Actions, Roll Inspection.

2:40 PMRoll Failure Analysis (Invited)G. Ott, J. Sychterz*, Union Electric Steel, USA

Abstract Not Available

3:20 PMRoll Inspection Equipment (Invited)A. Payling*, Sarclad North America LP, USA

Abstract Not Available

Special Topics: Perspectives from EmergingMaterials Professionals: Early Strategies forCareer Development

Key Strategies for Career Development IIRoom: 403Session Chairs: Nathan Ashmore, The Boeing Company; EmilyKinser, IBM

2:10 PMCan You Spell Entrepreneur? (Invited)L. Hanke*, Materials Evaluation and Engineering, Inc., USA

Abstract Not Available

2:50 PMASM - You and the Engineering Needs of the Future (Invited)R. Fabian*, Bodycote Thermal Processing, USA

Challenges faced by industry and society will largely be met by tech-nology – and many necessary advances will be driven by new devel-opments in materials science and engineering. Our ability to developand implement materials and process solutions will directly impactour ability to ensure the security of our citizens, create sources for al-ternative energy, improve our global environment and improve ourquality of life. As a scientific and engineering society that serves ourprofession, ASM and our Strategic Plan reflect the challenges faced byour membership and our world, particularly in terms of emergingand disruptive technologies. Progress made in the USA, as comparedwith the rest of the world, will illustrate where we stand in meetingthe engineering challenges of the future. While we have a long way togo to meet our own engineering needs in the world economy, ourEmerging Professionals have indicated a strong commitment to meetthe challenge.

3:50 PMNavigating International Waters: Perspectives from OverseasMaterials Laboratory Implementation ExperienceJ. Auliff*, Sauer-Danfoss, USA

Abstract Not Available

4:10 PMGE Aviation’s Edison Engineering Development Program and Lifeafter the ProgramM. Maly*, General Electric Aviation, USA

Abstract Not Available

4:30 PMThe Benefits of Society Involvement to the Emerging ProfessionalJ. Frafjord*, U.S. Dept. of Energy, USA

Abstract Not Available

Electronic & Magnetic Materials: Fabrication,Microstructures and Interfacial Properties ofMultifunctional Oxide Thin Films

Preparation and Properties of Oxide FilmsRoom: 315Session Chairs: Kui Yao, Institute of Materials Research andEngineering; Matthew Chisholm, Oak Ridge National Laboratory

2:00 PMHeterolayered Pb(Zr0.52Ti0.48)O3/CoFe2O4 Multiferroic ThinFilms (Invited)J. Wang, C. Sim*, R. Zheng, A. Pan, National University of Singapore,Singapore

There is a unique combination of magnetization and polarizationoffered by the magnetoelectric effect in multiferroic thin films. Dueto the incompatibility of the magnetism and ferroelectricity in asso-ciation with the transition metal d¬-electron, few real multiferroicstructures with significantly large magnetoelectric coefficient exist.We have investigated the heterolayered thin films consisting ofCoFe2O4 and Pb(Zr0.52Ti0.48)O3. To modulate their multiferroicbehaviour, the PZT constituent layer thickness was systematicallyvaried, giving rise to a number of new phenomena in association ofinter-layer stress and interfaces, as well as the coupling between theferroelectric and ferromagnetic ordering. A significant improve-ment in saturation magnetization (Ms) was observed, where the en-hancement increases with increasing PZT layer thickness. We pro-pose a unique feedback mechanism, which is shown to exist in themultiferroic structure and is responsible for the observed multifer-roic behaviour.

2:40 PMGrowth of BST Films with a Seeding Layer and Application inUncooled IR Pyroelectric Detector (Invited)Y. Li*, J. Zhu, C. Wu, W. Zhang, State Key Laboratory of Electronic ThinFilms and Integrated Devices, China

BST thin films were deposited on Pt/Ti/SiO2/Si substrate with a verythin Ba0.65Sr0.35RuO3 by RF sputtering. The microstructure wascharacterized by X-ray diffraction and atomic force microscopy, re-spectively. XRD patterns show that BSR seeding layer had a signifi-cant influence on the orientation of BST thin films with highly a-axistexture. It was found that the dielectric properties of BST films wereaffected by the seeding layer. Comparing with BST thin films directlyon Pt-Si substrates, the dielectric relaxation was greatly suppressedand dielectric constant was increased due to the reduction interface

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 199

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania200

oxygen vacancies at interface. Additionally, J-V measurement indi-cated that the leakage current could be reduced for the buffer-in-duced BST thin films. The pyroelectric coefficient is 1.1×10-6C.cm-2K-1 at 6V/μm at room temperature. We fabricated single-elementdevices with the detecting rate of devices of 8.7×107cm.Hz1/2W-1.

3:40 PMFabrication and microstructure of the BaTiO3 thin films on TisubstrateJ. Jiang*, J. He, E. Meletis, The University of Texas at Arlington, USA; Z. Yuan,J. Liu, J. Weaver, C. Chen, University of Texas at San Antonio, USA; B. Lin, V.Giurgiutiu, University of South Carolina, USA; R. Guo, A. Bhalla, Universityof Texas at San Antonio, USA

Ferroelectric BaTiO3 has excellent piezoelectric properties and isconsidered as a good candidate for developing unobtrusive piezoelec-tric wafer active sensor arrays for structural health monitoring. Suc-cessful fabrication of barium titanate BaTiO3 on Ti will have signifi-cant importance for the development of such applications. This workreports the successful fabrication attempts of BaTiO3 thin films onthe titanium substrates using PLD and their microstructures andproperties. Electron microscopy studies reveal that BaTiO3 films arecomposed of crystalline nanopillars with average sizes from 100 nmto 200 nm. The BaTiO3 films have good interface structures andstrong adhesion with respect to Ti substrates by forming a grain sizegradient rutile TiO2 intermediate layer. The ferroelectric polarizationmeasurements show that the as-deposited BaTiO3 films possessingnearly the same spontaneous polarization as the bulk BaTiO3 ceram-ics, and indicate that ferroelectric domains are formed in the films.

4:00 PMDevelopment of ferromagnetic oxide semiconductor thin filmstowards spintoronics applications (Invited)K. Fujita*, Kyoto University, Japan

Magnetic semiconductors with Curie temperature beyond roomtemperature have attracted considerable attention since they are ex-pected to be promising candidates for spintronics applications. Oneapproach toward the development of magnetic oxide semiconductorsis to explore semiconducting materials that are known to show ferro-magnetism or ferrimagnetism above room temperature. In this study,epitaxial thin films composed of ilmenite(FeTiO3)-hematite(Fe2O3)solid solution have been prepared by the pulsed laser depositionmethod, and their electrical and magnetic properties have been ex-amined. A single phase of the ordered phase can be obtained underthe limited deposition conditions. The resultant order-phased filmsare ferrimagnetic above room temperature, and the conduction type(p- and n-type) can be controlled by the composition. Research onepitaxial growth of magnetite(Fe3O4)-based room-temperature fer-rimagnetic semiconductor thin films will be also demonstrated.

Electronic & Magnetic Materials:Ferroelectrics and Multiferroics

Single Crystals/RelaxorsRoom: 318Session Chairs: Xiaoli Tan, Iowa State University; ArmenKhachaturyan, Rutgers University

2:00 PMControl of Ferroelectric and Magnetic Phases in MultiferroicCompounds through External Pressure and Substitutions(Invited)B. Lorenz*, R. P. Chaudhury, University of Houston, USA; C. R. dela Cruz,University of Tennessee, USA; C. Chu, University of Houston, USA

The ferroelectricity in multiferroic materials is strongly coupled tothe magnetism and in a large class of multiferroics the electric polar-ization is even induced by the inversion symmetry breaking magnetic

order. The control of magnetic exchange coupling or anisotropy con-stants seems to be imperative to gain a deeper insight into the com-plex relations between ferroelectric and magnetic orders, their mutualinteractions, and their coupling to the lattice. We use external pressureand ionic substitutions to achieve the goal of tuning magnetic cou-pling parameters and investigate the consequences on the ferroelec-tric state. Multiferroic compounds investigated in this study includeRMn2O5 (R = Ho, Dy, Tb, Y), Ni3V2O8, and Mn1-xFexWO4. All materi-als show a remarkable sensitivity of their multiferroic properties withrespect to the chosen control parameter (pressure or substitution).

2:40 PMDielectric and ferroelectric properties in the Pb(Mg1/3Nb2/3)O3-PbZrO3 solid solution with long range cation orderX. Zhao*, X. Tan, Iowa State University, USA

The 1:1 B-site cation order was successfully developed in thePb(Mg1/3Nb2/3)O3-PbZrO3 solid solution through slow cooling dur-ing sintering. Substituting both Mg2+ and Nb5+ with Zr4+, which has alarge ionic radius (0.72Å), facilitates the development of long rangecation order. The enhanced chemical order was revealed by x-ray dif-fraction and it is in sharp contrast to previous studies by other re-searchers, where a disordered structure was claimed. The impact ofcation ordering on the dielectric properties and the electric field in-duced phase transition in the Pb(Mg1/3Nb2/3)O3-PbZrO3 ceramicswas investigated in detail. It was found that typical relaxor ferroelec-tric behavior was preserved even in ceramics with a high degree ofcation order. The results were discussed on the basis of the relation-ships between chemical cation order and electric dipole order.

3:40 PMEnhanced piezoelectricity in relaxor ferroelectrics: aphenomenological approach (Invited)J. Liu*, Nanjing University, China

Relaxor ferroelectrics (RFs) have excellent piezoelectric perform-ances, which offer fascinating domain configuration consisting ofnanoscaled ferroelectric domains embedded in the paraelectric ma-trix. Nevertheless, an intrinsic relationship between the excellentpiezoelectric performance and the specific domain configuration re-mains to be confirmed. We intend to develop such a relationshipwithin the phenomenological framework. We start from the dipoleconfiguration of RFs doped with defects by utilizing the Ginzburg-Landau equation. We demonstrate that the role of long-range elasticenergy in RFs is less important than in normal ferroelectrics. A phasediagram of temperature-defect density for RFs is then constructed,which identifies four distinct phase regimes. Subsequently, we investi-gate the polarization and electromechanical behaviors of RFs as gen-erated above. A clean relationship between the piezoelectric responseand the characteristic size of the ferroelectric clusters is established.

4:20 PMFatigue Crack Growth Behavior of PMN-PT Piezoelectric SingleCrystalsM. Pan*, E. P. Gorzkowski, Naval Research Laboratory, USA

To date, most research on piezoelectric single crystals emphasizedcrystal growth and property enhancement and little was knownabout their fatigue and fracture behavior of under operating condi-tions. In this study we aimed to develop an understanding of thecrack growth habit in lead magnesium niobate-lead titanate (PMN-PT) due to electrical fatigue. As our preliminary observation indi-cated that most cracks occur in the primary crystallographic direc-tions, we prepared three sets of specimens with the electrode surfacenormals aligned in these directions. Unipolar electric field was usedto avoid domain switching and it was kept below the phase transfor-mation threshold. The crack growth under an AC electric field (up to2 kHz) is recorded under an optical microscope. The crack growthrates are determined as a function of crystallographic direction and

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 200

Wed

nes

day

PM

www.matscitech.org 201

electric field amplitude. The findings and their implications for trans-ducer designs will be discussed.

4:40 PMPolarized Raman spectroscopy study of relaxor-ferroeelctricPbSc0.5Nb0.5O3 single crystalA. Kumar*, R. S. Katiyar, UPR, USA; S. Lushnikov, Ioffe Physical TechnicalInstitute, Russian Federation

Lattice dynamical characteristics of PbSc0.5Nb0.5O3(PSN) single crys-tal were studied using polarized Raman spectroscopy over a widerange temperature i.e. 80-1300 K. The Raman spectra are good agreewith others cubic relaxors same as PMN or PST. The polarized lightwith off-diagonal spectra consist of the F2g Raman active mode withcharacteristic frequency ∼49.4 cm-1 and the diagonal spectra has A1gRaman active modes ∼813 cm-1. Temperature dependence of the in-tegrated intensity and Raman line widths were discussed in the lightof diffuse phase transition (DPT) and Burns temperature. High tem-perature Raman studies revealed the anomalous in Raman spectra:there are disappearing above 1000 K. Dielectric spectra showedbroader frequencies dispersion at dielectric maximum temperaturein heating process compared to the cooling process suggests chemi-cally disordered crystal. We have also observed the specific heatanomaly near the room temperature matched well dielectric spectra.

5:00 PMThe effect of NaNbO3 substitution into Pb(Zn1/3Nb2/3)O3-PbTiO3single crystal on the piezoelectric propertiesJ. Park*, Korea Institute of Science and Technology, South Korea; J. Lee,University of Pittsburgh, USA; K. Hong, Seoul National University, South Korea

The Pb(Zn1/3Nb2/3)O3-5PbTiO3 single crystal was modified by theNaNbO3 and the behavior of the E-field induced phase transition, thepiezoelectric properties and the permittivity maximum tempera-ture(Tmax) of <001> oriented crystals were investigated. When the2.5mol% NaNbO3was added in the PZN-5PT, the Tmax decreasedfrom 175oC to 150oC and the phase transition electric field decreasedfrom 22kV/cm to 12kV/cm. And the piezoelectric constant (d33) in-creased from 1600pC/N to 3500pC/N which was the remarkablepiezoelectric properties and higher than the greatest value of PZN-PTsolid solution (2500pC/N). However, when the content of NaNbO3increased from 2.5mol% to 5mol%, the Tmaxdecreased to 130oC andthe E-field induced phase transition couldn’t be found. And thepiezoelectric properties decreased to 1200pC/N. Such changes ofpiezoelectric properties with the contents of NaNbO3 were correlatedwith the ordering degree of B-site cation measured by the Ramananalysis.

Electronic & Magnetic Materials:International Symposium on AdvancedDielectric Materials & Electronic Devices

Design, Preparation, and ApplicationRoom: 317Session Chair: K.M. Nair, E.I. duPont de Nemours & Co. Inc.

2:00 PMMulti-functions of LaNiO3 Layer for Integrated BaTiO3 Film on Si(Invited)K. Kato*, S. Kayukawa, K. Tanaka, K. Suzuki, National Institute of AdvancedIndustrial Science and Technology, Japan

BaTiO3 is one of the main lead-free materials for dielectric, piezo-electric, and electro-optic applications. The films have received muchattention as the integral fulfilled capacitors. In our previous work,(100)-oriented BaTiO3 films synthesized using a Ba-Ti double alkox-ide solution have been characterized. The unique columnar structuredeveloped on Pt-coated Si substrates with LaNiO3 nucleation layers.

In this paper, the multi-functions of LaNiO3 bottom layer such as anucleation promoter, a buffer of residual stress and a conductive elec-trode, are discussed. The LaNiO3 layers were deposited using chemi-cally-designed solutions. The crystallographic, microstructural andelectrical properties were characterized in the single layer and also theintegrated structure with the BaTiO3 films. The BaTiO3 films exhib-ited good dielectric and piezoelectric properties on the multifunc-tional LaNiO3 layers. The ferroelectric to paraelectric transition wasaddressed in the dielectric constant-temperature behaviors.

2:20 PMRecent Investigations of Cobaltite Thermoelectric Materials atNIST (Invited)W. Wong-Ng*, M. Otani, G. Liu, E. Thomas, N. Lowhorn, Q. Huang, P.Schenck, M. Green, NIST, USA; J. A. Kaduk, INEOS Technologies, USA

Currently there is increased interest in research and development onthermoelectric materials because of the soaring global energy de-mand. The discovery of novel thermoelectric oxides was of consider-able importance because of their high temperature stability. The lay-ered cobaltite family that includes NaCoO2, Ca2Co3O6, andCa3Co4O9, has showed promise because of the combination of largeSeebeck coefficient and low electrical resistivity. This paper will give abrief introduction of the current thermoelectric materials research,followed by a discussion of structure and thermoelectric properties ofseveral series of layered cobaltite compounds, including those in theternary oxide system, Ca-Sr-Co-O. Our efforts using the high-throughput combinatorial synthesis approach for (Ca,Sr,La)3Co4O9films, and designing a novel screening tool to study the thermoelec-tric properties of thermoelectric thin films will also be described.

2:40 PMPercolation Modeling in Composite DielectricsV. Chaswal*, V. K. Vasudevan, R. C. Buchanan, University of Cincinnati, USA

Percolation modeling plays a doubly significant role in bulk dielectrichetero-structures. It can be used to predict sintering evolution in themanufacture of these multi-phase ceramics, and also model theirmacroscopic electronic response, like permittivity and conductivity.While complex analytical techniques have also been tried to estimatethese properties, underlying indeterminacy in interfacial area, mor-phology, shape and size of constituents phases are often not takencare of. Alternatively, percolation modeling provides a realistic andviable solution. This article investigates the scope of Percolationmodeling in structural and electronic design of hybrid dielectric het-ero-structures. We demonstrate using simple 1-D and 2-D models,on how Percolation modeling identifies important characteristics forapplication specific design, and property evaluation of bulk compos-ite, electronic dielectrics in terms of the nature, size and shape of theirconstituent phases.

3:40 PMNanocalorimetric Investigation of Interfacial Stability inAdvanced Electronic Materials (Invited)L. P. Cook*, R. E. Cavicchi, W. F. Egelhoff, C. B. Montgomery, NIST, USA

Interfacial stability is critical for the performance and reliability ofhighly integrated thin-film structures being developed for next-gen-eration device applications. Thin-film nanocalorimetry, which canmeasure the thermal signatures associated with interfacial reaction,provides an efficient method for screening of interfacial stabilities. Inthis paper, we describe use of a MEMS differential scanning calorime-ter (DSC) with a sensor area of 66 μm x 120 μm and a detection limitof < 5 nJ to measure the enthalpy of interfacial reaction in a 100 nmNi/100 nm Si bilayer. We demonstrate that the nanocalorimetricmethod can be used to investigate interfacial reaction kinetics over awide range of heating rates.at temperatures up to 560 °C. The capa-bilities and limitations of the approach for the study of interfacial re-actions in dielectric materials are discussed.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 201

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania202

4:00 PMCharacterization of SMA and polypyrrole actuator for humanoidface (Invited)Y. Tadesse*, S. Priya, Virginia Tech, USA

Various actuator technologies have been studied for facial muscleswith the goal of mimicking the face. Each of these actuators havemerits and demerits but none satisfy all the criterion in terms offorce, displacement, response time constant, power, size, and cost. Inthis presentation, we will present a comparative study of two promis-ing actuator technologies, shape memory alloy (SMA) and conduct-ing polymer composite actuators. The characterization of the actua-tors was done in terms of response time, force – displacement curves,power consumption and fabrication methods. Further, these actua-tors were used to prototype a face. Results will be presented on thisprototype to demonstrate the applicability in practical scenario.

4:20 PMPreparation and Electrical Properties of Multilayer ZnO Varistorswith Water-based Tape CastingL. Wang*, G. Tang, Tsinghua University, China; Z. Xu, City University ofHong Kong, China

Multilayer ZnO varistors were prepared by water-based tape castingwith water-soluble acrylic as binders. Zeta potentials of the dopedZnO suspensions as a function of pH with and without D134 weremeasured. Viscosity measurements were used to find the optimumdispersant concentration needed to prepare a stable slurry. Viscosityproperties of the slurry were investigated. The results showed thataqueous acrylic binders have shear thinning properties suitable fortape casting of ceramic powders. Scanning electron microscopy(SEM) studies revealed that the green sheets have a smooth defect-free surface and that the multilayer varistor ceramics have a fine grainmicrostructure with a uniform grain size and dopant distribution.The multilayer ZnO varistors prepared by water-based tape castingdisplay comparable good electrical properties to those prepared bysolvent-based tape casting. Therefore, water-based tape casting issuitable for the manufacture of multilayer ZnO varistors.

4:40 PMDielectric Properties of Rare Earth doped Sr-M HexaferritesB. Singh Anterpreet*, T. Kulwant Singh, N. Sukhleen Bindra, Guru NanakDev University, India; K. R.k, National Physical Laboratory, India

Strontium hexaferrites of a structural formula Sr1-xRExFe12O19,where RE = La3+, Nd3+ and Sm3+ with (x = 0 to 0.30) were pre-pared by a standard ceramic technique. The lattice constants, density,porosity, dielectric constant and dielectric loss tangent were studiedon a series of rare earth doped strontium hexaferrites. The dielectricconstant and dielectric loss tangent were measured in the frequencyrange of 20Hz to 1 MHz at room temperature. The dielectric constantdecreased with increasing frequency for all the three series. This be-havior of dielectric properties with frequency has been explainedwith the Maxwell–Wagner type interfacial polarization in agreementwith the Koops phenomenological theory. The substitution of rareearth ions into SrFe12O19 increases the value of the dielectric con-stant. This could be due to the electronic exchange between Fe2+ ÄFe3+ and results in a local displacement determining the polarizationof the ferrites. Curie temperature decreases as rare earth ions substi-tution increases.

5:00 PMPiezoelectric Behaviour of the Blended Systems (NYLON 6 /NYLON 11)S. A. Pande*, H Raisoni College of Engineering, India; D. S. Kelkar, Instituteof Science, India; D. R. Peshwe, Visvesvaraya National Institute ofTechnology, India

Some materials have the ability to change shape or size simply byadding a little bit of heat, or to change from a liquid to a solid almost

instantly when near a magnet; these materials are called smart mate-rials. It can adaptively respond to changing stimuli e.g., the variabledarkening of photo chromic glass or plastic on exposure to sunlight.By definition, smart structures and materials are those which cansense external stimuli, via internal sensing and/or actuation, and re-spond with active control to those stimuli in real or near-real time.Four of the most widely used classes of smart materials are piezo-electrics, electrostrictors, magnetostrictors, and shape-memory al-loys. Smart materials undergo two or more phase transformations,which can be used to tune their performance. Smart materials alsocan be manufactured by using multifunctional composites. Thesecomposites are made by combining two materials in a connectivitypattern that optimizes the functionality of the composite.

Electronic & Magnetic Materials: LowTemperature Processing for Integration ofMicroelectronics Devices

Piezoelectric IntegrationRoom: 319Session Chair: Paul Clem, Sandia National Laboratories

2:00 PMShear Mode Ultrasonic Motor and Ink-jet Head Using Lead-FreeAlkaline Niobate Ceramics (Invited)T. Tsurumi*, E. Li, R. Suzuki, Tokyo Institute of Technology, Japan; S. Uraki,Konica Minolta IJ Technologies, Inc., Japan; T. Hoshina, Tokyo Institute ofTechnology, Japan

Lead-free piezoelectric ceramics have been intensively studied inmany research groups to meet the demand of environmental protec-tion from the usage of toxic lead in electronic products. However, theperformance of most of lead-free materials is still insufficient to de-velop piezoelectric devises. We have been focused on the high piezo-electric activity of the shear mode of KNbO3-based materials and re-cently succeeded in developing ultrasonic motors and ink-jet headsusing shear mode of these materials. For the ultrasonic motor appli-cation, a piezoelectric material with a high mechanical quality factor(Qm) as well as a high piezoelectric d-constant should be developed.We have found the co-doping of CuO and Li2O to (K, Na)NbO3 ce-ramics markedly improve the Qm due to the domain pinning effectof internal bias-field and have succeed in developing a new composi-tion which showed the Qm of 1,400. A shear mode type ultrasonicmotor was designed using finite element method.

2:40 PMLow temperature processing of piezoelectric thick films bydesigning of powder morphology and composition (Invited)M. Kosec*, J. Holc, D. Kuscer, Jozef Stefan Institute, Slovenia

Paper describes key issues in processing of piezoelectric thick films onvarious substrates. In order to lower sintering temperature two ap-proaches have been used. Powder is prepared by high energy milling inorder to assure high chemical homogeneity and fine particle size. Sin-tering is conducted in a presence of transient liquid phase. PZT, PMN-PT and lead free KNN based thick films are prepared on alumina aswell as LTCC substrates. Reactivity of LTCC towards piezoelectric filmsis controlled by sintering conditions and barrier layer respectively. Aresonance pressure sensor based on PZT on LTCC is demonstrated.

3:20 PMPulse excimer laser annealing of ferroelectric thin films for MEMsapplications (Invited)S. Bharadwaja*, R. Akarapu, S. Trolier-McKinstry, The Pennsylvania StateUniversity, USA; H. Beratan, D. Arbuthnot, L-3 Communications IP, USA

Ferroelectric thin films have applications including pyroelectric de-tectors, piezoelectric transducers, and tunable microwave devices, but

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 202

Wed

nes

day

PM

www.matscitech.org 203

Pb-based ferroelectric films are crystallized at temperatures ≥ 600°C.To enable CMOS integration, we present a KrF pulsed excimer laser(248nm) annealing method. Polycrystalline, perovskite PLZT thinfilms were produced for substrate temperatures of 250°C and higher.The dielectric constant and loss tangent of laser assisted crystallizedPLZT films, processed for 2-3 minutes at 400°C substrate tempera-ture, were 406 and 0.027. Laser annealed films exhibited a pyroelec-tric coefficient ~16-18 nC/cm2K between 50-110°C, comparablewith conventionally processed PLZT thin film samples. Finite ele-ment simulations of heat propagation and the associated temperaturedistribution across the film stacks will be discussed. These results in-dicate laser annealing is an efficient method to integrate the ferroelec-tric thin films on temperature sensitive substrates.

Electronic & Magnetic Materials: PerovskiteOxides: Films, Nanostructures, Properties,and Applications

Physical Properties of Perovskite Oxides IIRoom: 316Session Chair: Ashok Kumar, University of Puerto Rico

2:00 PMMultiferroics phenomenon in Pb(B`B``)O3 relaxor thin films andceramics (Invited)R. S. Katiyar, A. Kumar*, M. Correa, I. Rivera, UPR, USA

We synthesized single phase multiferroics Pb(Fe2/3W1/3)1-xTixO3(PFWT, x=0-0.50) by chemical solution deposition,PbFe2/3Nb1/3O3 (PFN) and PbSc2/3Nb1/3O3 (PSN)-PbFe2/3Nb1/3O3 thin films using pulse laser deposition techniqueand its ceramics by solid state reaction route. PFWT (x=20) showedmultiferroicity near the room temperature. It illustrated strong com-petition between short and long range ordering with weak ferromag-netic properties. Polycrystalline PFN ceramics showed room temper-ature diffuse ferroelectric and ferromagnetic properties. A broadanti-ferromagnetic transition is observed in zero field cooled PFNthin film with a Neel temperature (TN) ~ 120K. Microstructure anddielectric properties of PbSc0.50Nb0.25Ta0.25O3 (PSNT) thin filmsrevealed an in plane compressive strain producing the relaxor behav-ior. Multiferroic properties of PSN-PFN thin films and nano ceramicswill be discussed.

2:40 PMStudies on Gas Sensing Performance of(Ba0.8Sr0.2)(Sn0.8Ti0.2)O3 Thick Film ResistorsV. B. Gaikwad*, K.T.H.M. College, Nashik, India; L. A. Patil, Pratap.College,Amalner, India

The (Ba0.8Sr0.2)(Sn0.8Ti0.2)TiO3 (BSST) was preparedmechanochemically sintered at 1000°C. Thick films of BSST wereprepared by screen-printing techniques. The gas sensing performanceof the BSST was tested for various gases. The BSST showed tempera-ture programmed sensitivity, The BSST showed exceptional, interest-ing and unique results. BSST could select different gases at differentoperating temperatures. For example, it selects NH3 at 250°C, H2S at300°C, ethanol at 350°C, and Cl2 at 400°C. The gas response, selectiv-ity, response and recovery time of the sensor were measured and pre-sented. The role played by surface copper species in the gas sensingperformance is discussed.

3:40 PMPreparation and Electrical Properties of lanthanum-manganese-nickel and lanthanum-manganese-indium oxides (Invited)C. Kao*, P. Hsu, National Cheng Kung University, Taiwan

The precursors of lanthanum-manganese-nickel and lanthanum-manganese-indium oxides were prepared by chemical coprecipita-tion. Firstly,indium oxide were reacted with hydrochloric acid to ob-

tain the corresponding chloride. Coprecipitation was carried outfrom the appropriate ratios of ammonium hydroxide to lanthanumnitrate, manganese nitrate,and nickel nitrate or indium chloride. Co-precipitates were collected by filtration and drying. The better crys-tallinity of the powder occurred at 973 K for 10 h for La-Mn-Ni ox-idesas examined by XRD. And occurred at 1073 K for 10 h forLa-Mn-In oxides. Calcined powder was pressed into a disk then sin-tered at various temperatures and times. The electrical resistivity ofmaterial doped with nickel is lower than that of doped with indium.The dielectric constant of material doped with calcium or doped withindium was also determined.

4:20 PMMetal oxides as possible thermoelectric material (Invited)Q. Li*, Pennsylvania State University, USA

Layered cobaltates have recently been considered for thermoelectricapplications, stimulated by the discovery of a large thermoelectricpower in metallic NaxCoO2. The thermoelectric figure of merit ofNaxCoO2 can be comparable to semiconductors at high temperatures.Unconventional mechanism of spin entropy effect due to strongly cor-related electrons has been proposed to be responsible for the large See-beck coefficient. We have fabricated and studied epitaxial thin films ofseveral cobaltates including NaxCoO2, LixCoO2, and layered Bi-Sr-Co-O. Both in situ epitaxial films grown by pulsed- laser deposition aswell as topotaxial films converted from epitaxial Co3O4 films havebeen achieved. Their electrical properties varies from metallic to semi-conducting and their Seebeck coefficient changes from 100 μV/K to380 μV/K at room temperature. Electrical and thermoelectric proper-ties of these cobaltate films will be discussed and the thermoelectricproperties of epitaxial and topotaxial films will be compared.

5:00 PMThe Effect of Electrode Materials on Resistive Switching inHeterostructures Containing Manganese PerovskitesJ. Meador*, S. Choi, M. Noman, R. Hussin, J. A. Bain, M. Skowronski, P.Salvador, Carnegie Mellon University, USA

Resistive switching in top electrode (TE) / functional-layer (FL) / baseelectrode (BE) heterostructures is thought to occur, in part, by themovement of oxygen vacancies near the FL/electrode interfaces. In thiswork, a comparative investigation was carried out in which SrRuO3,LaNiO3, La0.6Sr0.4CoO3, and Pt were used as TE and BE materials withA0.7Sr0.3MnO3 FLs, where A = La and Pr. Results indicate that the switch-ing behavior is a strong function of electrode material, as BE materialswith higher oxygen affinities show a larger delta-R than those with loweroxygen affinities. I-V characteristics were registered and were consistentwith the existence of large interfacial resistances. These results will bediscussed with respect to FL thickness and electrode type. The work pre-sented here discusses the interfacial nature of resistive switching andsupports the theory that resistive switching is caused by mobile defects.

Environmental & Energy Issues: Frontiersin Materials Science: Closing the NuclearFuel Cycle

Advanced Nuclear FuelsRoom: 326Session Chair: Srinath Viswanathan, University of Alabama

2:00 PMThermodynamics of Advanced Oxide Nuclear Fuels (Invited)M. Stan*, Los Alamos National Laboratory, USA; P. Cristea, University ofBucharest, Romania; S. Y. Hu, Pacific Northwest National Laboratory, USA; B.Mihaila, M. Valone, A. D. Andersson, L. A. Morales, K. J. McClellan, LosAlamos National Laboratory, USA; J. C. Ramirez, Exponent, Inc. , USA

Thermodynamic properties of nuclear fuels containing significantfractions of minor actinides (advanced fuels) strongly depend on

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 203

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania204

temperature, composition and microstructure. In particular, the ac-cumulation of fission products and the formation of gas bubbles candecrease the thermal conductivity, leading to the overheating of thefuel element. In this presentation the effects of multi-scale phenom-ena on properties such as thermal conductivity, oxygen diffusivity,and phase stability are reviewed. Based on atomistic evaluations offree energies, a model of point defects concentrations and interac-tions is proposed and applied to oxide nuclear fuels based on PuO2-xand UO2+x to predict equilibrium stoichiometry and oxygen diffu-sivity. Furthermore, the phase field method is employed to study theeffect of microstuctural changes on thermal conductivity of fuel andcladding materials. The phase field model takes into account the gen-eration of gas atoms, gas atom diffusivity inhomogeneity, and gasatom segregation.

2:40 PMAdsorption of Uranium and Cadmium from Process Solutions(Invited)Z. Zhang, R. Reddy*, University of Alabama, USA

Studies were carried out on the adsorption of uranium and cadmiumfrom process solutions by zeolites. Effects of time, pH of the solutionand type of zeolite viz. chabazite, mordenite, erionite and clinoptilo-lite on the adsorption of U and Cd from solutions were investigated.Chabazite has been found to be most effective. The adsorption onchabazite was higher followed by clinoptilolite, erionite and morden-ite. The higher adsorption capacity of chabazite has been attributedto (i) higher pore volume: Chabazite has higher pore volume, 35.3pct. in comparison to other zeolites and (ii) Si/Al ratio: chabazite hasthe lower Si/Al ratio of all the other zeolites. If all the factors areequal, a lower Si/Al ratio in zeolites corresponds to higher zeolite ca-pacity. Studies showed that chabazite is the most effective adsorbentin comparison to other zeolites. Increase in temperature moderatelyincreased the removal of cadmium. Possible sorption mechanismswere proposed.

3:40 PMFabrication of (U,Dy)N Fuel PelletsB. J. Jaques*, B. M. Marx, M. F. Hurley, D. D. Osterberg, D. P. Butt, Boise StateUniversity, USA

The complex mix of actinides that are separated via the uranium ex-traction (UREX)-type processes must be synthesized into useful fuelforms to enable a closed fuel cycle. Nitrides have been identified aspossible fuel materials for several Generation IV reactor designs.They are favored over other fuel forms due to a combination ofhigher actinide loadings, higher thermal conductivities, and lowerthermal expansion coefficients. In order to avoid the difficulties ofworking with actinide bearing materials, 238U and dysprosium ni-trides were used in place of 235U and americium nitrides. DyN hasbeen identified as a surrogate for AmN primarily due to its volatilenature as well as crystal structure and lattice parameter. In the presentstudy, UN, DyN, and their solid solutions (Ux, Dy1-x) (x = 1 to 0.7)were studied. The effects of sintering were investigated by varying thesintering temperature, time, and atmosphere to determine the effectson the density and final microstructure. Insight to the kinetics of sin-tering is also presented.

4:00 PMPhysico-chemical Properties of Erbia-Bearing Super HighBurnup FuelS. Yamanaka*, M. Katayama, K. Kurosaki, M. Uno, Osaka University, Japan;M. Yamasaki, T. Kuroishi, Nuclear Fuel Industries, Ltd, Japan

Addition of low density erbia to all the uranium powders with en-richment more than 5wt% will make it possible to develop super highburnup fuel in Japanese nuclear facilities which is now under the re-striction of the upper limit of fuel enrichment 5wt%. In order to de-velop the erbia-bearing super high burnup fuel it is necessary to studyon the physco-chemical properties of erbia added urania as the fresh

fuels. In this study, U1-xErxO2 (0<0.1<) pellets with O/M ratioabout 2.00 were made by sintering the sample powders at 1873K inflowing H2-Ar gas for 5 hours and then at 1373K in a desired reduc-ing gas for 40 hours and the physico-chemical properties were meas-ured. Young’ modulus decreased with erbium content. The thermalexpansion of the samples increased slightly even if 10% addition ofErbium was made to UO2. Thermal conductivity decreased withtemperature and Erbium content.

4:20 PMCharacterization of Oxide Precipitates Observed as a Gray Phasein High-Burnup Mixed Oxide Fuels for Fast ReactorsK. Kurosaki*, Osaka University, Japan; K. Tanaka, M. Osaka, Japan AtomicEnergy Agency, Japan; T. Maekawa, H. Muta, M. Uno, S. Yamanaka, OsakaUniversity, Japan

It is very important to understand the behaviour of the fission prod-ucts (FPs) for evaluation of the fuel performance. For example, in thehigh-burnup oxide fuels, some FPs dissolve in the fuel matrix andothers form the oxide or metallic precipitates, which would affect thephysical and chemical properties of the fuels. Here we show the char-acteristics of the oxide precipitates; especially we focused on (Ba,Sr)-Mo-O ternary compounds because they would take various chemicalforms under the different oxygen potentials. We found that the ther-mal conductivities of (Ba,Sr)MoO3 are approximately 10 times higherthan those of (Ba,Sr)MoO4 (~3 Wm-1K-1). Present study includes theresult of “Study on the physical properties of nuclear fuels with multiphase system: Toward establishment of the closed cycle system withlow-decontaminated oxide fuel” entrusted to Osaka University by theMinistry of Education, Culture, Sports, Science and Technology ofJapan (MEXT)

Environmental & Energy Issues: Fuel Cells:Materials, Processing, Manufacturing,Balance of Plant and Systems Operation

Corrosion, Degradation and Protection TechnologiesRoom: 325Session Chairs: S.K. Sundaram, Pacific Northwest National Lab;Chun Lu, Siemens Energy

2:00 PMStructural Degradation Mechanisms of SOFCs Anode and FEA forLong Term Anode Material Behavior in Coal Syngas Environment(Invited)G. Iqbal, B. S. Kang*, West Virginia University, USA

Coal Syngas based SOFCs is the future technology for clean power gen-eration. Several degradation mechanisms damage SOFCs anode mate-rial depending on loading and working conditions. Thermal stresses,thermal aging and redox cycle in coal syngas environment can degradethe anode structural integrity by reducing their load carrying capabilityand service life. Continuum Damage Mechanics (CDM) predicts theonset and evolution of material damage in an apparently undamagedmaterial, its remaining strength and life. This research aims to developa CDM model in ABAQUS through a user defined material subroutine,which takes into account damage mechanisms that degrade the SOFCanode to predict the long-term structural integrity of the anode undersyngas environments. The proposed model will be validated by experi-mental data. The extent of degradation will be determined by measur-ing the deformation profile of button cells subjected to various tests.

2:40 PMDevelopment of a New Aluminizing Process to MitigateChromium Volatility in Planar SOFC StacksJ. Choi*, S. K. Weil, Pacific Northwest National Laboratory, USA

The resistance of alloys against high temperature oxidation dependson the formation of a protective scale, such as Cr2O3, Al2O3, or

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 204

Wed

nes

day

PM

www.matscitech.org 205

SiO2. Among these, low-cost chromia-forming steels find widespreaduse in SOFCs at temperature below 1000°C. However the vaporiza-tion of Cr-containing species from this scale poisons the cathode ma-terial in the cells and subsequently causing power degradation inthese devices. This presentation will discuss the development of a newprocess (reactive air aluminizing; RAA) that results in a stable, Cr-freeoxide coating. The process is a powder-based technique that employsdiffusion between stainless steel and aluminum in an air environ-ment. The basic concept will be outlined and results (Cr volatility,thermal expansion, etc.) obtained in using this technique to coat var-ious ferritic stainless steel stack components will be described. In ad-dition, a mechanism of how the process provides oxidation and Crvolatility protection will be discussed.

3:40 PMAutomotive Composite Fuel Cell Bipolar Plates: EnvironmentalStress Cracking and Adhesive Bonding ConcernsR. H. Blunk*, D. Lisi, Y. Lai, V. Kumar, General Motors R&D Center, USA

Polymeric composite bipolar plates for PEM fuel cells are formulatedat high graphite loadings and molded thin in an attempt to reduceelectrical resistances and, in turn, compete with metal plates in volu-metric power density. The unipolar composite plates are joined to-gether with conductive adhesives and assembled into stacks at highcompressive loads to further reduce electrical contact resistances.These stack compressions and gas pressures can generate undesirabletensile and compressive/shear stresses in the manifold and land/chan-nel flowfield regions, respectively. The plates are subjected to harshfuel cell conditions—elevated stresses, 80°C, 100% RH—and are thussusceptible to environmental stress cracking and adhesive bond fail-ures. Results from long-term creep and voltage-drop studies indicatethat composite plate materials are sufficiently durable throughproper plate designs and adhesive selection.

4:00 PMOxidation behavior of Crofer 22 interconnects for SOFC incoal syngasY. Li*, R. Ravi Dastane, Y. Jiang, X. Liu, West Virginia University, USA; C.Johnson, R. Gemmen, National Energy Technology Laboratory , USA

Coal syngas is of interest for its economic use as a fuel for solid oxidefuel cells (SOFC). The oxidation behavior of Crofer 22 has been stud-ied separately in air and coal gas atmosphere at 1073K for up to 500hours. The scale thicknesses in both atmospheres were almost thesame. However, the morphology of the corrosion surface and the re-sults of a line scan of the cross section were much different. Thespinel broke out in chains in coal syngas while it broke out in clustersin air. Fe could diffuse to the surface of the scale in the coal gas butthere was little Fe on the sample surface obtained in air. Differences ofoxidation formation have been explained by thermodynamic stabil-ity. In addition, the ASR results showed that with the pre-oxidizedfilm formed in air 100h at 1073K, the material was hard to oxidize insyngas.

4:20 PMEmbrittlement of Palladium Membrane Grain Boundary by SulfurSegregationR. Le Gall*, A. Hassini, H. Mourton, Nantes University, France

Palladium membranes are widely used to separate hydrogen fromother gases in order to avoid contamination of fuel-cells. Thin palla-dium membranes (20 μm) aged about 150 hours at 600°C under purehydrogen, were found to exhibit many cracks along grain boundaries.Measurements of intergranular chemistry of aged membranes usingAuger microscopy showed that some boundaries were significantlycontaminated by sulfur. This is a direct evidence that sulfur segregatesat palladium grain boundaries. Sulfur is well known to embrittlegrain boundaries in many metals and alloys such as nickel, copper,thus it is reasonable to estimate that this mechanism can be, at leastpartially, responsible for live time limitations of palladium mem-

branes in such applications. Moreover, Auger analysis suggest thatsulfur comes from the inconel porous subtrate that supports themembrane, although its sulfur nominal concentration is as low as 100wt ppm.

4:40 PMDefects in CaFeO3-δδ perovskiteS. Lee*, V. R. Manga, Z. Liu, The Pennsylvania State University, USA

(LaxCa1-x)FeO3-δ is a potential candidate for cathode materials in solidoxide fuel cell. However, its defect chemistry and energetics have notbeen completely understood. Therefore, a combined approach offirst-principles calculations and CALPHAD (CALculation of PHAseDiagram) modeling of this phase can lead us to a better understand-ing of its defect structure. For the first step of modeling, it is requiredto model the CaFeO3-δ phase. It has been reported that the major de-fect mechanism for the CaFeO3 is the charge disproportionation of Fewhich brings structural change, charge ordering, magnetic ordering,and metal-insulation transition below 290 K. In this work, the chargedisproportionation in CaFeO3 is investigated by first-principles cal-culations and subsequently applied in the thermodynamic modeling.The enthalpy of formation of oxygen vacancy as a function of com-position is presented. The oxygen vacancy concentration as a func-tion of partial pressure of oxygen and temperature are obtained.

Environmental & Energy Issues: GreenTechnologies for Materials Manufacturingand Processing

Environmentally Benign Process IIRoom: 323Session Chairs: Mrityunjay Singh, Ohio Aerospace Institute; KojiWatari, AIST

2:00 PMMicrowave Assisted Technologies for Ceramics and ChemicalProcessing (Invited)S. M. Allan*, Ceralink Inc, USA

Microwaves are being used to assist ceramic and chemical processingwith surprising results, including fast reactions and new materialsproperties. Many discoveries have been limited to laboratory scalework, waiting on appropriate industrial microwave equipment. Theneed for equipment and process development to occur in concert isnow being addressed. This talk focuses on the scale-up and commer-cialization of microwave assisted processes and equipment. New com-mercially available equipment will be described, including microwaveautoclaves and microwave assist kilns. A review of important applica-tions relevant to diverse industries will be given. These include cata-lysts, phosphors, electroceramics, and nanomaterials. Specific exam-ples will be discussed, including 1) calcination reactions and sinteringof ceramic products using Microwave Assist Technology (MAT) and2) precious metal reclamation with microwave autoclaves.

2:40 PMGreen Manufacturing Strategy and Approach for ReducingOrganic BindersK. Watari*, K. Sato, T. Nagaoka, AIST, Japan

Environmental process technologies relating binder process for ce-ramic fabrication have been devoloped. One is to minimize greatlythe amount of organic binders. Other is to employ inorganic sub-stances instead of organic binders for conventional processing. Wehave focussed a thin-film of chemically bonded organic binder onparticles surface by microwave irradiation as new organic binder andhydraulic alumina as a inorganic binder to consolidate Al2O3 ceram-ics. The processing strategy and its experimental result will bedemonstrated.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 205

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania206

3:40 PMEnvironmentally Benign Utilization of Fossil Fuel ResourcesS. K. Sundaram*, G. G. Muntean, Pacific Northwest National Laboratory, USA

Pacific Northwest National Laboratory (PNNL) has worked for overthirty years in the area of gasification and hydrocarbon conversions.Focusing on indigenous coals as the raw material and recognizing thecritical constraints of air and water neutrality, the Energy ConversionInitiative (ECI) has recently been created to address the conversion ofcoal (and other hydrocarbon feed stocks) to synthetic fuels and prod-ucts. The ECI aims to better understand and develop the various coal-to-products systems in an integrated way, seeking to identify the sci-ence and technology challenges and needs as well as define theconditions for commercial success of coal gasification-derived syn-thetic products. Once the process capabilities have been demon-strated in pilot or full-scale commercial plants, further deployment ofthe technologies should help reduce the nation’s dependence on for-eign oil and mitigate market uncertainties. An overview of our re-search on materials and sensors for coal gasification will be presented.

4:00 PMSintering Behavior of Si3N4 Ceramics Prepared by Energy-savingPost-reaction TechniqueT. Wakihara*, H. Yabuki, J. Tatami, K. Komeya, T. Meguro, YokohamaNational University, Japan; H. Hyuga, H. Kita, Advanced Industrial Scienceand Technology, Japan

Si3N4 ceramics are known to be important materials as structuralmaterials. Post-reaction sintering technique is one of the fabricationprocess of Si3N4 ceramics, which has received much attention as en-ergy-saving, cost-effective process. Many researches on the develop-ment of this method have been performed, so far in order to improvetheir properties; however, sintering shrinkage behavior, which is veryimportant information to optimize the firing condition, has not beenwell clarified. In this study, we focused on Si3N4 and SiO2 powders asdiluents for nitridation of Si (exothermic reaction) in Si-Y2O3-Al2O3 system, and investigated the effect of the additives on the sin-tering shrinkage behavior of post-reaction sintering process for thefabrication of Si3N4 ceramics by dilatometory.

4:20 PMUltrahigh Porous Cordierite with Micrometer-sized Cells forEnvironmetal PurificationM. Fukushima*, M. Nakata, Y. Yoshizawa, National Institute of AdvancedIndustrial Science and Technology (AIST), Japan

Ultrahigh porous cordierite with oriented micrometer-sized cells,which is useful for environmental purification, was prepared by novelgelcasting method. Gelation agent, water for pore former andcordierite powder were mixed and gelled. The resultant gel obtainedwas cooled, dried around 10-35°C, degreased at 600°C and sintered at1200-1400°C for 2hr. The porous cordierite showed ultra highlyporosity around 87-93%. SEM observations of porous cordieriteshowed the microstructure of orderly uni-directionally oriented mi-crometer-sized cell. The cell in the cross section had the size around20-50um in the diameter and the wall thickness of 2-5μm. Number ofcell was about 400-1500 cells/mm2. Compared to previous reports,the porosity and the number of cell are larger, and size and wall thick-ness of cell are much smaller. The pore size distribution by Hgporosimetry showed a bimodal distribution. The resulting porouscordierite with 87% total porosity showed a compressive strength ofabout 4MPa.

4:40 PMLow-cost Solid Geopolymeric Material for Water PurificationM. Alshaaer*, B. El-Eswed, R. Yousef, F. Khalili, H. Khouri, University ofJordan, Jordan

This research aims to develop water purification geopolymers withhigh mechanical properties produced at low temperatures from nat-

ural raw materials. As a case study, the adsorption of heavy metalsions onto these geoploymers prepared by solid-state conversion wasinvestigated. The adsorption isotherms were obtained and the lang-muir parameters were calculated in order to make a comparison be-tween the adsorption capacities of geopolymers and those of theirconstituents. The results showed that geopolymerization in the pres-ence of natural zeolitic tuff leads to an increase of adsorption towardheavy metals ions, Cd(II) , relative to the precursors. This is due tothe increase of surface area upon destruction of the precursor’sstructure, as shown by XRD, and the generation of new cation ex-change sites upon geopolymerization. In addition, these geopolymersshow high strength, 20 MPa, with relatively low density. Thus, theycould be used in water transportation, storage and other construc-tion applications.

Environmental & Energy Issues:Thermoelectric Materials: Science,Technology and Applications

Thermoelectric Materials Properties andCharacterizationsRoom: 324Session Chairs: Jihui Yang, General Motors R&D Center; ThierryCaillat, NASA Jet Propulsion Laboratory

2:00 PMInfluence of Microstructure on Transport Properties of BulkThermoelectrics (Invited)H. Wang*, Oak Ridge National Lab, USA

Bulk thermoelectrics are used in both refrigeration and power gener-ation applications. These semi-conducting compounds or alloys havecomplex microstructures and behave like typical brittle ceramics.Thermal and electrical transport properties are the most importantparameters to evaluate thermoelectric material performance. In themeantime, these properties are highly sensitive to the microstructureof the materials. In addition to the intrinsic transport properties,thermoelectric material research must also pay close attention to themicrostructure development. A number of bulk materials, such asbismuth telluride, skutterudites and TAGS, are used as examples todemonstrate the influence of microstructure on transport properties.It is also pointed out that the mechanical properties of the bulk ther-moelectrics are also dependent on the microstructure. This is moreimportant to module and device level design and practical applica-tions of thermoelectrics.

2:30 PMLanthanum Telluride for High Temperature ThermoelectricApplicationA. F. May*, Caltech, USA; J. Fleurial, Jet Propulsion Laboratory, USA; G.Snyder, Caltech, USA

The thermoelectric properties of lanthanum telluride (La3-xTe4) arecharacterized to 1273K for 0.03<x<0.33. A low temperature, mechan-ical alloying synthesis reduces concerns associated with the tradi-tional, high-temperature synthesis that tends to alter composition.The carrier concentration is directly proportional to the number oflanthanum vacancies, which results in a metal-insulator transition asx changes from 0 to 1⁄ 3. Therefore, varying x allows the influence ofcarrier concentration on thermoelectric properties to be examined.The thermoelectric properties demonstrate trends of a heavily-dopedsemiconductor for x≤0.33: the Seebeck coefficient and electrical resis-tivity increase as temperature increases and carrier concentration de-creases. Several compositions are found to have zT greater than one at1273K. A single-band analysis indicates lanthanum vacancies are im-portant in reducing lattice thermal conductivity at large x, and elec-tron-phonon interactions reduce thermal conductivity at small x.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 206

Wed

nes

day

PM

www.matscitech.org 207

2:50 PMEffect of V, Nb and Ta Additions on Thermoelectric Propertiesof Directionally Solidified Single-Phase Half-Heusler(Zr,Hf)NiSn AlloysY. Kimura*, H. Ueno, Y. Mishima, Tokyo Institute of Technology, Japan

Thermoelectric power generation is an appealing approach for con-serving energy. We focus on half-Heusler compounds that can beused to convert the waste heat into clean electrical energy at hightemperatures around 1000K. Half-Heusler compounds MNiSn(M=Zr,Hf) are well-known to show excellent n-type thermoelectricproperties. The additions of n-type dopants V, Nb and Ta were con-ducted on base-alloys of (Zr0.5Hf0.5)NiSn whose lattice thermalconductivity can be most effectively reduced by the solid solution ef-fects. In order to evaluate actual thermoelectric properties, nearly sin-gle-phase alloys were fabricated by directional solidification using thefloating zone melting method. The additions of V, Nb and Ta effec-tively reduce electrical resistivity and thereby enhance the power fac-tor, while thermal conductivity increases with carrier concentration.The 0.25at%Nb addition is the most effective among all the alloysprepared in this work.

3:40 PMStructural analysis of thermoelectric AgSbTe2 and(AgSbTe2)x(PbTe)1-x using high resolution transmission electronmicroscopy (Invited)L. Wu*, J. Zheng, J. Zhou, Q. Li, Brookhaven National Laboratory, USA; J.Yang, General Motors R&D Center, USA; Y. Zhu, Brookhaven NationalLaboratory, USA

(AgSbTe2)x(PbTe)1-x (or AgPbmSbTe2+m: LAST-m) compound is ofgreat interest due to its exceptionally high thermoelectric figure ofmerit (zT) and potential thermoelectric power applications. To under-stand the origin of the physical properties, an extensive structuralanalysis has been carried out using aberration corrected high-resolu-tion transmission electron microscopy. For LAST-18, nanoparticleswith different shape, size and structure have been observed and char-acterized. The nanoparticles were found generally rich in Ag and Sband well oriented within the matrix of the rock-salt type crystal withcoherent interfaces. The lattice mismatch of 1% to 6% at the interfacesresults in a localized strain field. For AgSbTe2, we found that the atomsorder along the [111] direction. Our Density Function Theory calcula-tions show that the ordered structure is energy favorable and may shedlight into the origin of the low thermal conductivity of this compound.

4:10 PMTEM Investigation of Nanoscale Substructures in IntermetallicThermoelectric MaterialsJ. Zhou*, L. Wu, J. Zheng, Y. Zhu, Brookhaven National Lab, USA; J. Yang,GM R&D Center, USA; Q. Li, Brookhaven National Lab, USA

Thermoelectric material can convert heat directly into electricity andhence may play an important role in the future energy production,conversion and utilization. The performance of thermoelectric mate-rials has been enhanced substantially in the last decade mostly due tothe nanoscale substructures in these materials. We report detailedTEM studies in a number of intermetallic thermoelectric materials,such as (AgSbTe2)x(PbTe)1-x and filled skutterudites. In particular,the evolution of the nanostructures and matrix materials as a func-tion of temperature up to the melting point has been investigated byin-situ TEM. The relationship between their nanostructures andthermoelectric properties will be discussed in this presentation.

4:30 PMEffect of porosity on the mechanical properties of Lead-Antimony-Silver-Tellurium (LAST) thermoelectric materialsJ. E. Ni*, F. Ren, E. D. Case, E. Timm, Michigan State University, USA; R. M.Trejo, E. Lara-Curzio, Oak Ridge National Laboratory, USA

Effect of porosity on the mechanical properties of Lead-Antimony-Silver-Tellurium (LAST) thermoelectric materials There is consider-

able interest in thermoelectric generators for a variety of applications,including the conversion of waste energy into electricity. LAST (Lead-Antimony-Silver-Tellurium) has a ZT (dimensionless figure of merit)of 1.7 at 700 K, which implies potential application of LAST materialsin the fabrication of thermoelectric generators with relatively high ef-ficiency at high temperatures. Porosity is important when looking atthermoelectric materials as porosity in brittle materials affects a rangeof electrical, thermal, and mechanical properties. Using the non-de-structive method of resonant ultrasound spectroscopy (RUS), the ef-fect of porosity on the room temperature Young’s modulus, shearmodulus, and Poisson’s Ratio are investigated for two LAST composi-tions and two fabrication processes (casting and hot pressing).

4:50 PMElectronic Structure and Thermoelectric Transport Properties of(Bi0.25,Sb0.75)2Te3: First-Principles CalculationsM. Oh*, B. Kim, S. Park, H. Lee, Korea Electrotechnology ResearchInstitute(KERI), South Korea

Bismuth-antimony telluride, (Bi, Sb)2Te3, is one of the most famousthermoelectric materials. Due to the dependency of the thermoelec-tric properties on electronic structures, the electronic structure ofBi2Te3 was intensively studied. However the result for (Bi, Sb)2Te3 isscarcely reported. In this study, the electronic structure of (Bi0.25,Sb0.75)2Te3, which is known as the best p-type thermoelectic materi-als in the vicinity of room temperature, was calculated within theframework of the density functional theory. To place the integer num-ber of each atom into the unit cell, the unit cell was enlarged twicealong the a- and the b-axes, which means 2×2×1 supercell. Two Biatoms are placed in the enlarged unit cell. The dependency of the totalenergy on the configuration of Bi-Bi pair was not observed. From theresult of the electronic structures, the thermoelectric transport prop-erties was estimated with the constant relaxtion time approximation.

Fundamentals & Characterization: CeramicSurfaces, Grain Boundaries and Interfaces

Self Organization and BiomineralizationRoom: 301Session Chairs: Helen Chan, Lehigh University; Ivar Reimanis,Colorado School of Mines

2:00 PMUsing Ice to Mimic Nacre: From Structural Materials to ArtificialBone (Invited)A. P. Tomsia*, E. Munch, E. Saiz, Lawrence Berkeley Lab, USA

In this presentation we describe new processing technique to fabricate hy-brid materials with unique lamellar and “brick and mortar” microstruc-tures that resemble nacre. The technique uses the directional freezing ofwater-based ceramic suspensions under conditions that promote forma-tion of lamellar ice. The ice crystals expel the ceramic particles and thesubsequent sublimation of water leaves a scaffold whose microstructureis the negative replica of ice. The scaffold is filled with a soft phase (metalor polymer) in order to combine a strong and hard phase with a “lubri-cating” layer in between to permit stress relaxation. Several approacheshave been formulated to control adhesion at the hard/soft interfaces. Theparameters (speed of the freezing front, particle size and additives) thatdetermine the microstructure of the materials are discussed. Our resultsshow ceramic-polymer and ceramic-metal hybrid materials with tough-ness well in excess of those expected from a rule of mixtures construction.

2:40 PMNano to Macroscale 3-D Biomineral Architecture of Red Coral(Invited)D. P. Vielzeuf*, N. Floquet, J. Garrabou, CNRS, France

Deciphering the structure of biominerals is challenging because oftheir complexity, the requirement of a wide spectrum of techniques,

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 207

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania208

and the integration of spatial observations covering several orders ofmagnitude. We used SEM, TEM and EMP to characterize the struc-ture of red coral. Annual growth rings correspond to the stacking ofstrata with tortuous interfaces due to the presence of micro protuber-ances. Strata are made of fibers, themselves composed of sub microncrystalline units possibly assembled by an oriented aggregationmechanism. HRTEM studies show that in spite of showing singlecrystal scattering behavior, the submicron units are made ofnanograins again possibly aggregated by a mechanism of oriented at-tachment. Submicron crystalline units and fibers can be both definedas mesocrystals. The red coral skeleton is thus a hierarchically organ-ized organic-inorganic composite with porosity, structural and com-positional order on length scales from the nm to the cm.

3:20 PMInfluence of electrical polarization on in vitro dissolutionbehavior of sol gel derived hydroxyapatite coatingS. Bodhak*, S. Bose, A. Bandyopadhyay, Washington State University, USA

We have investigated the influence of electrical polarization of sol-gelderived HAp coating on apatite crystal growth in SBF medium. A uni-form 20 μm thick HAp film was deposited on Ti substrate with HApslurry using a spin coater. HAp coating was polarized by application ofan external dc field (1 KVcm-1) at 400oC. The sign and magnitude ofinduced surface-charges depend on applied external dc field. Thermallystimulated depolarization current (TSDC) technique was used to meas-ure the stored charge within HAp coating. A moderate amount ofstored charge (1.7 μC/cm-2) was calculated from the TSDC spectra.The enhanced biomineralization of polarized HAp coating over un-treated HAp coating was demonstrated by in vitro SBF dissolutionstudy for 1, 5 and 7 days. SEM investigation revealed that accelerated ap-atite crystal growth was occurred on the negative charged surface, whereas apatite growth was decelerated on the positively charged surface.

3:40 PMDissociative chemisorption of water onto silica surfaces andenhanced hydronium ion formationS. Garofalini*, Rutgers University, USA

A new interatomic potential for water that allows for dissociation of thewater molecule and matches experimental liquid properties, such as theliquid equation of state, structure, diffusion, cohesive energy, dipolemoment, and frequency spectrum, was developed. No other interatomicpotential for water matches so many bulk water properties and also al-lows for dissociation. In addition to matching bulk water properties, ap-plication of this potential to simulations of water on silica surfacesshows dissociative chemisorption of the water molecules onto surfacesites, hydroxylation consistent with experiment, and, most importantly,surface reactions indicating the important role of hydronium formationin this behavior. These results are consistent with ab-initio calculationsof small systems as well as interpretation of experimental data. Applica-tion to water confined within nanoscale dimensions matches the anom-alously high expansion seen experimentally

Fundamentals & Characterization: Discoveryand Optimization of Materials throughComputational Design

3D Modeling and Design of MicrostructuresRoom: 303Session Chair: Nik Chawla, Arizona State University

2:00 PMThe development of anisotropic grain boundary characterdistributions: experimental observations and modeling (Invited)G. Rohrer*, CMU, USA

Recently developed techniques to measure the five-dimensional grainboundary character distribution or GBCD (the relative areas of dif-

ferent boundary types, distinguished by lattice misorientation andgrain boundary plane orientation) have been applied to a range ofmetals and ceramics. Based on these results, we are beginning to un-derstand how the GBCD evolves with time and is influenced by im-purities and processing conditions. One observation is that grainswithin polycrystals have preferred habit planes that correspond to thesame low energy, low index planes that dominate the external growthforms of isolated crystals. A second observation is the probable exis-tence of a steady state GBCD that is correlated to grain boundary en-ergies. Is this talk, the results of experiments and simulations are dis-cussed in terms of a simple theory for the development of steadystate, characteristic grain boundary character distributions will bedescribed.

2:40 PMMicrostructural Design of Materials for Optimized Performance(Invited)K. Thornton*, University of Michigan, USA

Microstructures are important in a wide range of materials becausetheir properties and performance depend on it. This is especially truein multifunctional, multiphase or composite materials in which dif-ferent phases perform different functions. Therefore, controlling mi-crostructures in these materials is one of the main routes for materialsdesign for optimal performance. Various simulation methods that canbe applied to examine processing, property, and degradation duringoperation, including the phase-field simulations and finite elementmodeling, will be discussed. Through coupling of simulations of mi-crostructural evolution and transport that uses realistic microstruc-tures, we examine microstructural design for optimized performance.Specific examples will include microstructures found in solid oxidefuel cell electrodes and those resulting from phase separation.

3:40 PMUsing Image-based Mesoscale Simulations to Identify CriticalMicrostructural Features (Invited)A. C. Lewis, Naval Research Laboratory, USA; S. Qidwai, Science ApplicationsInternational Corporation, USA; A. B. Geltmacher*, Naval ResearchLaboratory, USA

3D mesoscale image-based finite element models are used to identifycritical features in a 3D beta-Ti microstructure under mechanicalloading conditions. The microstructure is reconstructed using serialsectioning techniques, which provide information on grain morphol-ogy and crystallography. The reconstructions are inputted into 3D fi-nite element models using different mesh generation techniques toanalyze the spatial evolution of state variables in the microstructureunder loading. These models incorporate anisotropic elasticity andcrystalline plasticity to represent material response. The data ob-tained from simulations is used to interrogate correlations betweenmicrostructural features and local stress state. In this beta-Ti mi-crostructure, high stresses and strains are observed at grain bound-aries, and the morphological and crystallographic properties of theseboundaries have been analyzed to determine which factors generatehigh local strains under a variety of loading condition.

4:20 PMComputer Simulations of Realistic Three-DimensionalMicrostructures (Invited)A. M. Gokhale*, Y. Mao, Georgia Institute of Technology, USA

Current methodologies for microstructure simulations mostly in-volve idealized simple particle/feature shapes; uniform-random spa-tial distribution of microstructural features; and isotropic feature ori-entations. However, the corresponding “real” microstructures oftenhave complex feature shapes/morphologies; non-random/non-uni-form spatial distributions; and partially anisotropic feature orienta-tions. Consequently, such simulations do not capture these aspects ofmicrostructural reality. We present a methodology that enables simu-lations of realistic three-dimensional microstructures where feature

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 208

Wed

nes

day

PM

www.matscitech.org 209

shapes/morphologies, spatial arrangement, and feature orientationsare statistically similar to those in the corresponding real microstruc-tures. The simulation parameters used for generation of these mi-crostructures can be correlated to the process parameters. The corre-lations permit generation of a set of “virtual” microstructures thatcover a wide range of process conditions.

5:00 PMUnderstanding Deformation Behavior of Materials byMicrostructure-Based Simulations (Invited)N. Chawla*, Arizona State University, USA

A thorough understanding of microstructure is crucial in under-standing properties of engineering materials. In this talk, microstruc-ture-based finite element modeling of materials, in two and three di-mensions (2D and 3D), will be discussed. Realistic and accuratedescriptions of the microstructures are incorporated into the finiteelement model. In 2D, optical or scanning electron micrographs areused as a basis for the model. In 3D, a serial sectioning approach isused to obtain 2D sections through the depth of the material, fol-lowed by reconstruction and visualization of the 3D “virtual mi-crostructure.” This is followed by incorporation into a FEM code toelucidate both macroscopic and microscopic aspects of deformation.Examples applied to three important materials, Sn-rich Pb-free sol-der alloys, SiC particle reinforced Al composites, and sintered steels,will be discussed. The opportunities for discovery and optimizationof materials using this approach will be described.

5:40 PMStrain Prediction for Open-Celled Foams through 3D Imaging in aScalable Modelling EnvironmentJ. K. Farooqi*, F. C. Plaza, L. Margetts, P. Mummery, M. A. Sheikh, TheUniversity of Manchester, United Kingdom

Mechanical behaviour of open-celled foams is very complex due tolarge deformations and complex material response. Investigationshave been carried out by initial X-ray Tomography scanning, prepar-ing solid geometric models that are then analysed through finite ele-ment analysis. In a normal computing environment, the complexityof foam structure and associated 3D finite element mesh sizes com-pletely overshadow the scientific and engineering exercise in foam’scrush test to densification. This has been solved by using high per-formance computing systems for compression simulations on theselarge models across hundreds of parallel processors in a distributed-memory architecture platform. A specialised code ‘ParaFEM’ is usedwhich addresses the challenging task of running finite element analy-ses across that many processors while dealing with very large datasetseffectively. As a result bulk as well as localised straining has been suc-cessful predicted against actual in-situ strain maps.

Fundamentals & Characterization: FailureAnalysis for Problem Solving

Historical Case StudiesRoom: 304Session Chairs: Daniel Dennies, The Boeing Company; Brett Miller,IMR Test Labs; David Moore, Packer Engineering, Inc.

2:00 PMSWA Flight 1248 Incident at Midway Airport (Invited)D. Moore*, P. Fenoglio, Packer Engineering, Inc, USA

On December 8, 2005, Southwest Airlines (SWA) flight 1248, a Boe-ing 737-700, ran off the departure end of the runway after landing atChicago Midway Airport (MDW). The airplane rolled through a blastfence, and airport perimeter fence, and onto an adjacent roadway,where it struck an automobile before coming to a stop. A child in theautomobile was killed, several others were injured, and the airplane

was significantly damaged. Details of the investigation findings andexplanation of the causes and contributing factors will be presented.

2:20 PMPhoenix Wrought Iron Circa 1863 - Mechanical Fibering (Invited)F. E. Schmidt, Jr. - P.E.*, Engineering Systems Inc, USA

ASM designated the Phoenix Column an Historic Landmark in2006.These solid flanged/riveted columns were manufactured in 4, 5,6, 8, and 10 sections approximately 20 feet in length by a hot rollingmethod. A review of the mechancal properties and the microstruc-tural constituents reveals a dispersion of macro & micro inclusions.Controlled macro fracture tests were performed to establish the roleof composition and morphology on the surprising strong & flexiblecolumns. One of the most significant elements of composition is thepresence of ~0.40 percent Phosphorus. Nomarski metallographictechniques were especially useful. Phoenix columns were the orignalstructures used in early sky scraper design.

3:40 PMTexas A&M University Bonfire Collapse (Invited)D. Moore*, T. Carlson, Packer Engineering, Inc, USA

For over 90 years, the weeks leading up to the annual University ofTexas football game had seen the students of Texas A & M University(TAMU) building Bonfire, culminating in the ceremonial lightingand burning on the eve of the game. At approximately 2:30 a.m. onthe morning of November 18, 1999, while Bonfire was still underconstruction, there was a catastrophic structural collapse causing thefour existing log stacks to fall. The collapse resulted in 12 fatalitiesand 27 injuries. This presentation will provide details of the collapseinvestigation including the Bonfire construction history, specific 1999Bonfire construction conditions, and analysis to determine the causesof the collapse.

4:00 PMRevisiting the Molasses Spill of 1919 (Invited)G. A. Wildridge*, IMR Test Labs, USA

In January of 1919 residents fo the inner harbor area of Boston werestartled by “loud popping noises, like a machine gun”. Soon a wave ofmolasses approximately 15 feet high and traveling an estimated 35miles per hour tore through the area, claiming the lives of up totwenty-two people and numerous animals along with extensive dam-age to surrounding structures and houses. The disaster was the resultof catastrophic failure of a large molasses storage tank. A conclusiveroot cause has yet to be determined and remnants of the tank are nolonger available for examination by modern day failure analysts. How-ever, review of the available information using simplified fracture me-chanics and metallurgical engineering suggests that a combination oflatent causes and physical causes stemming from incomplete knowl-edge of fracture mechanics in design and inadequate design reviewand testing may be the most likely reasons for the disaster.

4:40 PMAn Historical Review of Fracture Control in Bridges (Invited)A. W. Pense*, Lehigh University, USA

Learning how to control failures in bridges has probably been an in-cremental process from the beginning of history, however, startingwith the use of iron and steel for major members in the 19th century,the failures of some bridges built with these materials, either in erec-tion or in service, have played a significant role in shaping our currentbridge design, fabrication and materials codes. Like it or not, it wasthe failures of these structures rather than laboratory experimenta-tion that led to the safer bridges we ride over today. This presentationtraces the failures or partial failures of five major bridges over the last100 years and describes how they changed the codes and standards bywhich we design and construct them. The bridges are the QuebecBridge (1907), the Tacoma-Narrows Bridge (1940), the Ohio Silver

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 209

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania210

Bridge (1967), The I-79 Neville Island Bridge (1977) and, finally, theI-35 Minneapolis Bridge (2007). The failure of this latter bridgedemonstrates that the process continues today. The presentation willdemonstrate that these failures did not only occur because of insuffi-cient or erroneous engineering but also because of many human fac-tors that are, unfortunately, still with us today.

Fundamentals & Characterization: Fatigue ofMaterials: Competing Failure Modes andVariability in Fatigue Life

Fatigue of Advanced MaterialsRoom: 305Session Chairs: D. McDowell, Georgia Tech; T. Nakamura, HokkaidoUniversity

2:00 PMThe Fatigue Behavior of Bulk Metallic Glasses and TheirComposites (Invited)P. K. Liaw*, G. Wang, university of Tennessee, USA; Y. Yokoyama, TohokuUniversity, Japan; L. Huang, M. Freels, D. Qiao, university of Tennessee, USA;A. Inoue, Tohoku University, Japan

Bulk-metallic glasses (BMGs) have been fabricated successfully since1990s. BMGs are being studied widely due to their great potential asstructural materials. For applications as structural materials, the fa-tigue behavior and a fundamental understanding of that behavior areimportant for the design of new alloy systems and the development ofnew processing techniques. High-cycle fatigue has been performed indifferent loading conditions and environments in our lab. The factorsaffecting the fatigue behavior are discussed, with particular emphaseson the fatigue-crack initiation and crack-propagation characteristics.The mechanism of crack initiation will be clarified. Moreover, the fa-tigue-crack-growth experiments were conducted to understand thecrack-propagation behavior in BMGs. The crack-growth mechanismwill be proposed.

2:40 PMFatigue Crack Initiation in Nickel-based Superalloy René 88DTat 593°°CJ. Miao*, T. M. Pollock, J. W. Jones, University of Michigan, USA

The fatigue behavior of a polycrystalline nickel-based superalloy,René 88DT, was investigated in the lifetime regime of 105- 109 cyclesat 593οC in both laboratory air and inert gas environment using anultrasonic fatigue testing apparatus. At 593οC in air, all fatigue cracksinitiated internally. Large crystallographic facets were observed atcrack initiation sites of most failed fatigue specimens. Critical mi-crostructure features associated with fatigue crack initiation wereidentified by the combination of serial sectioning, orientation imag-ing microcopy and quantitative fractographic analysis. Cyclic defor-mation substructures were characterized by transmission electronmicrocopy. The influence of the variation of critical microstructurefeatures on fatigue crack initiation and the variability of fatigue lifewere analyzed. The environmental effects on fatigue crack initiationin this alloy at 593οC will be discussed.

3:00 PMInfluence of Electrical Discharge Machining on the FatigueBehavior of Nano-Crystalline NiL. Lai, University of California, Irvine, USA; W. Chiou, University ofMaryland, USA; J. C. Earthman*, University of California, Irvine, USA

Electrical discharge machining (EDM) has been applied on variousfields for high precious machining purposes. However, its effects onthe fatigue behavior of nano-crystalline (nc) materials are not wellunderstood. The influence of electrical discharge machining (EDM)on the fatigue properties of electro-deposited nc Ni was investigated.

The presence of an EDM affected zone resulted in a dramatic de-crease in fatigue life for the same stress range. Rationale for theweaker resistance to fatigue damage can be attributed to grain growthand sulfur segregation at the grain boundaries in the EDM affectedzone. Also, the fatigue behavior of the nc Ni specimens that were fab-ricated using EDM was not strongly dependent on R ratio for valuesranging from 0.2 to 0.5. It appears that the influence of EDM resultsin early initiation of fatigue cracks which is affected little by loweringthe mean stress.

4:00 PMFatigue in High-Performance Titanium Hybrid Laminates(Invited)R. Dauskardt*, M. Oliver, Stanford University, USA; K. Blohowiak, BoeingPhantom Works, USA

Titanium-graphite (TiGr) thin foil laminates posses a range of supe-rior thermomechanical properties for high-performance aerospacestructures. These properties are closely linked to the performance ofthe interphase region comprising a number of thin-films between themetal and reinforced polymer layers. We describe recent researchleading to the development and characterization of state-of-the-artinterphase films consisting of thin (~100nm) adhesion-promotinghybrid sol-gel films and toughened epoxy adhesive layers with bond-line thicknesses of a few tens of microns. The effect of testing envi-ronment, temperature, loading mode mixity, and fatigue loading onfailure in the interphase region is described. We describe methods toboth process and characterize wide ranges of compositions and glassstructures to assess the effects on the laminate properties. Implica-tions for TiGr laminate reliability are discussed.

4:40 PMSmall fatigue crack growth modeling and its implications forworst-case life predictionA. Shyam*, E. Lara-Curzio, Oak Ridge National Laboratory, USA; J. Jones,University of Michigan, USA; J. E. Allison, Ford Motor Company, USA

An interesting aspect of structural materials that exhibit competingfatigue failure mechanisms is that the lifetime of “short-life” failurescan be estimated based on small fatigue crack growth behavior. Amodel for small fatigue crack growth and its application for cast alu-minum, wrought aluminum, nickel-base and titanium alloys will bedescribed. The model is predicated on dislocation-based fracture me-chanics concepts and the applicability of the model is verified bycharacterization of the small fatigue crack growth rates in a variety ofexperimental conditions. The assumptions of the model are experi-mentally assessed by studying the behavior of a 2024 type aluminumalloy and in particular by measuring the striation spacing on the frac-ture surface. In addition, the striation spacing measurements provideinsight into the variation of the slopes of the small crack growthcurves. A worst-case fatigue lifetime prediction methodology basedon the described model will be presented.

5:00 PMFatigue Crack Growth Resistance of Nanocrystalline CopperR. K. Rajgarhia*, C. Jackson, A. Saxena, University of Arkansas, USA

Fatigue crack growth behavior of 99.99% nanocrystalline copperwith grain size less than 100 nm has been studied and compared to itsmicrocrystalline counterpart. The nanocrystalline samples were pre-pared using equal channel angular extrusion process as per the 4Eprocessing route at room temperature. The microcrystalline sampleswere prepared from commercial Cu-101 (99.99%) material and nor-malized at 500 °C for 2.5 hours. All samples were tested as per theASTM E647 standard at room temperature under tension-tensionloading and data over a wide range of stress intensity levels has beenpresented. A cross-over in the behavior of two materials has been ob-served showing that the nanocrystalline copper has a higher fatiguecrack growth resistance over the middle Paris regime but a lower fa-tigue crack growth resistance in the near threshold regime. Micro-

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 210

Wed

nes

day

PM

www.matscitech.org 211

hardness and TEM measurements will be conducted in the plasticzone near the crack tip to check for any grain growth that may causethe cross-over behavior.

Fundamentals & Characterization:International Symposium on Defects,Transport and Related Phenomena

Defects and Transport in Ceramics IIIRoom: 307Session Chairs: Thomas Mason, Northwestern University; DavidCann, Oregon State University

2:00 PMKinetics of Cation Distribution and Diffusion in CobaltContaining Olivines (Invited)K. D. Becker*, J. Shi, Technische Universität Braunschweig, Germany

In the olivine structure, the divalent cations occupy two inequivalentsites, M1 and M2. In cobalt containing olivines, (CoxMg1-x)2SiO4, theCo2+ ions prefer the smaller M1 site. With rising temperatures, how-ever, the M2 site becomes increasingly populated by cobalt ions.Thus, the redistribution of cations over M1 and M2 sites in (CoxMg1-

x)2SiO4 olivines can be induced by sudden temperature changes. Inthis presentation, the kinetics of Co-Mg intersite exchange in(CoxMg1-x)2SiO4 olivines with x=0.1 and 0.6 have been studied from500-800°C by means of in-situ optical spectroscopy combined withthe temperature-jump relaxation technique. Cation diffusivities inthe olivines derived from the kinetic data were found to be 3 orders ofmagnitude smaller than those extrapolated from high-temperatureliterature data, which is explained in terms of crystallographic orien-tation and point defect association effects.

2:40 PMEXAFS of ZITO Thin FilmsD. Proffit*, D. Buchholz, R. Chang, M. J. Bedzyk, T. O. Mason, NorthwesternUniversity, USA; Q. Ma, Northwestern Synchrotron Radiation Center atAdvanced Photon Source, USA

Zn-In-Sn-O materials (ZITO) are promising alternatives to In-Sn-O(ITO) for transparent electrode and transparent semiconductor ap-plications. The local structures of crystalline and amorphous Zn-In-Sn-O (c-ZITO, a-ZITO) thin films grown by pulsed laser depositionwere determined by x-ray absorption spectroscopy (XAFS). Measure-ments around the Zn-, In-, and Sn-K absorption edges were taken atthe Advanced Photon Source at Argonne National Laboratory andthe first nearest neighbor and second nearest bond distances and co-ordination numbers were obtained. The short bond distances and rel-atively large coordination numbers of Sn-O provide evidence for theFrank-Köstlin cluster, which was first seen in ITO. Two distinct Zn-Ofirst nearest neighbor distances indicate a more complicated defectmechanism associated with the substitution of Zn for In. These re-sults are discussed with reference to the underlying defectstructure(s) of ZITO and ITO.

3:40 PMUsing Isotope Exchange and Diffusion to Probe Space-chargeLayers at Interfaces in Complex Oxides (Invited)R. De Souza*, RWTH Aachen Universtiy, Germany

The combination of 18O / 16O exchange and Secondary Ion MassSpectrometry (SIMS) analysis constitutes a powerful tool for probingoxygen transport processes in oxides. In this contribution, after abrief introduction to the technique and its capabilities and limita-tions, I demonstrate the application of this method to two unusualcases in which the diffusion coefficient, because of the presence of thespace charge, varies at a function of position. Specifically, I present re-cent work on 18O transport (i) in dense ceramics of nanocrystalline

yttria-stabilised zirconia (YSZ) [1] and (ii) through the space-chargelayer at the surface of single crystal SrTiO3 [2]. 1. R. A. De Souza, M. J.Pietrowski, U. Anselmi-Tamburini, S. Kim, Z. A. Munir and M. Mar-tin, Phys. Chem. Chem. Phys., (2008). DOI:10.1039/b719363g 2. R.A.De Souza and M. Martin, Phys. Chem. Chem. Phys., (2008).DOI:10.1039/b719618k

4:20 PMNew Aspects of Defect Structure in CaTiO3-BaTiO3 Solid SolutionsS. Lee*, G. Yang, C. A. Randall, The Pennsylvania State University, USA

Defect structures in CaTiO3-BaTiO3 solid solutions have been sys-tematically investigated in regard to the electrical properties forMLCC applications. A conventional conductivity measurement wasused to understand the defect chemistry in the Ca multi-site occupiedCaTiO3-BaTiO3 solid solutions. With the phase transition tempera-ture and lattice volume variations, the site occupancy was confirmedby modifying Vegard’s law. Unlike the conventional plot of log σ vs.log Po2, the electrical conductivity as a function of oxygen partialpressure (Po2) shows much more complicated Po2 dependence underlow Po2 conditions and also shows a different profile with differentgas mixture, such as H2/N2 and CO/CO2 gas mixtures. From the con-ductivity data as a function of temperature we were able to obtain thedefect energetics with different compositions. This study will discussthe Ti4+/Ti3+ reduction and also hydrogen and/or proton effects in thedefect chemistry analysis.

4:40 PMTransport and Capacitance Behavior of CuO/ZnO HeterocontactInterfaces (Invited)D. Cann, Y. Jeon, B. Gibbons*, C. Dandeneau, Oregon State University, USA

Heterocontact sensors based on p-CuO/n-ZnO exhibit a strong DCand AC electrical response to the presence of reactive gas species.These sensors operate on the principle of measuring a change in in-terfacial impedance due to the adsorption of surface reactive gases atthe interface. In this work, the critical factors that determine the elec-trical response will be examined. Thin film and bulk ceramic hetero-contact sensors were prepared and the transport characteristics weremeasured in the presence of multiple gases at temperatures up to500°C. Furthermore, through modeling of time-dependent conduc-tivity measurements, the kinetics of gas adsorption at the interfacecan be analyzed. The capacitive response was explored in both the fre-quency and time domain and the response was dominated by the dif-fusion capacitance while the depletion layer capacitance was largelyunaffected. With these findings, an improved understanding of theimportant sensor mechanisms will aid in optimizing heterocontactsensors.

Fundamentals & Characterization: Micro-and Nano- Mechanical Behavior of Low-Dimensional Structures and Materials

Micro- and Nano- Mechanical Behavior of Materials -Soft MatterRoom: 308Session Chairs: Charles Lu, University of Kentucky; MichelleDickinson, Hysitron, Inc.

2:00 PMNanoindentation in Polymeric Materials (Invited)S. Lee*, C. Liu, C. Lin, National Tsing Hua University, Taiwan

The problem is considered polymeric materials under an action ofnanoindentation load. This problem can be solved using a modelbased on the Burgers viscoelastic concept. The Burgers model con-sists of Maxwell element connected with Kelvin element in series. The

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 211

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania212

displacement at the indenter tip was derived from the analog of gov-erning equation of elasticity in the time domain to that of viscoelas-ticity in the Laplace transformation coordinate system. Using the an-alytical solution of elastic displacement at the indenter tip andLaplace inverse transformation, the viscoelastic displacement at theindenter tip is yielded. Nanoindentation and creep tests for polymericmaterials such as PMMA, polycarbonate were proceeded to verify thetheoretical model. Young’s modulus and hardness were obtained andcompared with those in literature. *This work was financially sup-ported by the National Science Council, Taiwan.

2:20 PMAccuracy Improvements in the Mechanical Analysis of Polymerswith an Atomic Force Microscope (AFM)G. Moeller*, Arkema Inc., USA

Understanding the mechanical behavior of nanostructured polymersis of great academic and practical interest. We applied AFM nanoin-dentation to measure mechanical properties of such materials. WhileAFM is generally acknowledged as a high-resolution imaging tool, ac-curate quantification of AFM nanoindentation results is a challenge.We report significant accuracy improvements for modulus measure-ments of polymers when special large end-radius tips are used for in-dentation and viscoelastic contact models are applied for data analy-sis. Using these tips results in only minor loss of imaging resolutionso that very small regions of interest can be identified and indentedfor mechanical analysis. We show AFM results obtained with differenttips and under different loading conditions for five polymers and twopolymer blends and a comparison with instrumented indenter re-sults. Accuracy improvements achieved range from 10% to 70% de-pending on polymer and loading conditions.

2:40 PMNano scale deformation mechanisms in semi-crystalline polymer:in situ atomic force microscopy study and modellingF. Detrez*, Universite des Sciences et Technologies de Lille, France; S.Cantournet, Ecole des Mines de Paris, France; R. Seguela, G. Coulon,Universite des Sciences et Technologies de Lille, France

The aim of this work is to study the deformation mechanisms at thenano-scale within the spherulitic structure of semi-crystalline poly-mers. The deformation mechanisms are imaged by Atomic Force Mi-croscopy (AFM). The originality of this work is to place a home-made tensile drawing stage under the AFM head in order to performin situ tensile tests. The observations performed on several semi-crys-talline polymers (polyamide 6, polybutene, polycaprolactone) showthat the fragmentation of crystalline lamellae is the dominant mech-anism of plastic deformation. Cyclic tensile tests reveal the damagingcharacter of fragmentation mechanisms. Mechanical models are pro-posed to account for both macroscopic mechanical behavior andspherulitic morphology evolution.

3:40 PMCharacterizing the inelastic properties of polymer thin films andcoatings through cylindrical indentationY. Lu*, University of Kentucky, USA; D. M. Shinozaki, University of WesternOntario, Canada

Cylindrical indentation is used to characterize the inelastic propertiesof materials, mainly polymers, in small dimensions. The method isfirst used to measure the plastic properties of bulk polymers. Under acylindrical indenter, the material can quickly reach a fully plasticstate. The size of the plastic zone is constant in large strain regionsand unaffected by the exact tip profile. The indentation stress-dis-placement curve at large strains is linear as a result of the steady-stateplastic flow, from which the mean indentation pressure can be readilyextrapolated. The method is then extended to measure the interfacialfailure of polymer coatings adhering to rigid substrates. As the tip ap-proaches the substrate, the deformation field is constrained andforced to move outwards, which generates a large shear stress at the

interface. The critical interfacial shear strength can be estimatedbased on a modified shear-lag model.

4:00 PMNon-Destructive High-Resolution Nano-Mechanical Mapping OfLow-Dimensional Structures and MaterialsN. Gitis*, M. Vinogradov, V. Khosla, CETR, Inc., USA

Evaluation of nano-mechanical properties has been performed onpolyimide coatings in LCD displays and on composite polymers usedin automobiles and aircraft, utilizing a Nano+Micro Tester UNMT-1.We measured scratch-hardness of coatings, utilizing the same nano-tip for both scratching and nano-imaging under the constant load.We measured scratch-adhesion with the same diamond tip under thecontinuously-increasing load. We evaluated homogeneity of nano-composites by Young’s modulus and topography nano-mapping.<p>Nano-scratches of polyimide coatings at increasing and constantloads generated adhesion and scratch-hardness data, respectively. Wedetermined both the critical load of coating delamination and a cor-responding lateral force. The mutually complimentary nano-imagesand force graphs coincided nicely. <p>The Young’s modulus maps al-lowed us to evaluate the distribution of silica particles embedded inaraldite, revealed the effects of particle agglomeration.

4:20 PMNanomechanics of Self-Assembled Chiral Lipid Tubes (Invited)J. Fang*, L. An, University of Central Florida, USA

The rigidity of lipid tubes is a key factor that has a strong impact in theirapplications. In this talk, we present our work in understandingnanomechanics of chiral lipid tubes made of 1,2-bis(tricosa-10,12-diynoyl)-sn-glycero-3-phosphocholine (DC8,9PC). The interface ten-sion of shrinking liquid droplets exerts a compression force on the endsof the trapped tubes, and causes them to buckle. The axial Young’s mod-ulus of chiral lipid tubes is estimated to ~ 1.07 GPa. The local radial elas-ticity of chiral lipid tubules is studied by AFM indentation, coupled withfinite element analysis. A reduced stiffness is found to extend a distanceof ~ 600 nm from the ends of chiral lipid tubes. The middle section ofchiral lipid tubes is homogeneous in terms of their elasticity with a ra-dial Young’s modulus of ~ 703 MPa. The inhomogeneous radial elastic-ity near the ends of chiral lipid tubules and the difference between theaxial and radial Young’s modulus of chiral lipid tubes will be discussed.

4:40 PMWhat roles do nanostructures play in the strengthening andtoughening of nacre? (Invited)X. Li*, University of South Carolina, USA

The presentation reports the recent discovery of nanostructures in nacreand elucidates the roles that the nanostructures play in nacre’s deforma-tion and fracture. The nanostructures were found in individual aragoniteplatelets by both AFM and HRTEM. The combined HRTEM imagingand selected area diffraction techniques well explain the single crystallinecharacteristic of individual aragonite platelets. It was found that crackdeflection, organic adhesive interlayer, interlocking from surface nano-asperities, and rotation and deformation of aragonite nanoparticles allwork together to contribute to the plasticity (inelasticity) and energy dis-sipation in nacre. This presentation also presents future challenges in thestudy of nacre’s nanoscale structures and mechanical properties.

5:00 PMIndentation-Controlled Dissolution of 45S5 Bioactive Glass inPhosphate Buffer SolutionD. Li*, University of Kentucky, USA; M. Yang, C. Wu, P. Muralidhar, PaulLaurence Dunbar High School, USA; F. Yang, University of Kentucky, USA

The bioactivity and material dissolution of a bioglass depend on thestress state in the material. Using a spherical, diamond indenter inmicroindentation test, localized residual stresses were created in 45S5bioactive glasses, and cone cracks were observed for large indentation

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 212

Wed

nes

day

PM

www.matscitech.org 213

loads. The indentation-controlled dissolution of the 45S5 bioactiveglasses was studied in the phosphate buffer solution. The morpholog-ical evolution of the indented surfaces was characterized by scanningelectron microscopy and compared to that of the indentation-freesurface. Fast dissolution occurred over the contact zone between theindenter and the glass due to the surface damages created by the in-dentation. The local compressive residual stresses around the inden-tations significantly suppressed the long-time material dissolution.Such results provide a potential technique to control bioactivity andprevent premature failure of bioactive glasses through local stresstreatment.

5:20 PMQuantitative Modulus Maps of Wood Cell StructureJ. Schirer*, Hysitron, Inc., USA

Quasistatic nanoindentation has become a reliable method to quanti-tatively and accurately characterize mechanical properties in small-scale structures. Previously unattainable structure-property relation-ships in heterogeneous materials have been revealed by the site-specificprecision of nanoindentation. The spatial resolution of this methodwith plastic deformation is limited by a necessary spacing between in-dividual indents. To overcome this, dynamic nanoindentation hasbeen developed which can measure the modulus of surfaces within theelastic regime of sample testing which enables indents to be mademuch closer together. This study investigates the mechanical proper-ties of individual wood cells using a dynamic mapping techniquewhich allows the mechanical properties of the whole cell to be studiedat a much higher resolution than traditional quasistatic testing wouldallow. With this technique, the stiffness and modulus of individual cellcomponents can be easily visualized in a quantitative graphical form.

5:40 PMMicroindentation of hemlock leaf cushions: the first step tounderstanding susceptibility of hemlocks to insect attackP. Ayayee*, Y. Li, F. Yang, L. K. Rieske-Kinney, University of Kentucky, USA

Hemlocks are critical components of North American forests, regu-lating numerous ecosystem processes and providing critical wildlifehabitat. The hemlock woolly adelgid is an exotic invasive insect that iscausing widespread mortality in hemlock forests of the eastern USA.It feeds by inserting its piercing-sucking stylet into the xylem in theleaf cushion at the base of hemlock needles. To understand the sus-ceptibility of hemlocks to insect attack, microindentation was per-formed over the hemlock leaf cushions. The age-dependence of theindentation deformation was evaluated, including the indentationdepth and the energy dissipation. The results show that the old hem-lock leaf cushions are harder than the new leaf cushions.

Fundamentals & Characterization:Performance and Growth of Bulk and ThinFilm Materials - Role of Surface and InterfacePhenomena during Growth and Processing

Recent Advances in Growth of Inorganic and OrganicThin Film MaterialsRoom: 306Session Chair: Nuggehalli Ravindra, New Jersey Institute ofTechnology

2:00 PMGrowth Thermodynamics of Nano-scaled Alpha-AluminacrystallitesR. Yang*, P. Yu, National Cheng Kung University, Taiwan; C. Chen, Far EastUniversity, Taiwan; F. Yen, National Cheng Kung University, Taiwan

The growth thermodynamics of nano-scaled α-Al2O3 crystallitesafter its formation from θ-Al2O3 phase transition by thermal treat-

ment was examined. The crystallite growth characterized with quan-tum jump size increments can be performed through coalescenceprocesses. The α-Al2O3 nuclei with sizes 17-20 nm (dcα) coalescedto form α-crystallites of sizes 45-50 nm (dp), then by coalescence ofwhich the stable α-crystallites (ds) with minimum sizes 75-80 nmwere obtained. Coalescence of the ds crystallites leaded to formingthe crystallites with vermicular growth. A growth thermodynamicmodel describing the three-staged size growth was proposed. It pro-vides well-coincided calculations with the data observed. The surfacefree energy of θ-Al2O3 which has been the first time reported can be2.16 J/m2.

2:20 PMEffect of aligned nanorods in ZnO thin films for the enhancedphotoelectrochemical responseS. Shet*, K. Ahn, T. Deutsch, Y. Yan, J. Turner, M. Al-Jassim, NationalRenewable Energy Laboratory, USA; N. M. Ravindra, New Jersey Institute ofTechnology, USA

We have investigated the structural properties, optical absorption,and PEC responses for ZnO deposited at different temperatures bysputtering the ZnO target in pure Ar gas and mixed Ar/N2 gas ambi-ent. We found that the presence of N2 in the growth ambient help topromote the formation of aligned nanorods and impurity bands athigh substrate temperature of 500 °C, resulting in the significantlyenhanced PEC response, compared to ZnO(Ar) films deposited inpure Ar gas ambient. Our results suggest that deposition ambient canbe used to produce desired properties of thin films and alignednanorods may help to improve PEC performance.

2:40 PMGrowth and Characterization of Substituted Anilines forNonlinear Optical Applications (Invited)O. P. Singh, K.N.Government Post Graduate College, India; G. Singh, UPPower Corporation, India; R. N. Rai*, Banaras Hindu University, India

Many commercial and non commercial devices and need a high-av-erage power wavelength tunable laser source that can operate in thevisible and near-infrared wavelength range. To achieve this outputmust be shifted to the desired wavelength using nonlinear opticalmaterials. In addition to this, high electro-optic coefficient in mate-rial is required to achieve effective EO modulators and deflectors. Toperform this effectively, these materials must have a unique combina-tion of optical and mechanical characteristics. A great deal of workhas been performed in past three decades. For the low power applica-tions many organic materials have been studied. It is clear that or-ganic materials have high nonlinearity but due to stability and avail-ability these have not been utilized in devices. We have studied severalanilines and grown them by melt growth and physical vapor trans-port method. We will describe the details of growth and their opticalcharacteristics.

4:00 PMDevelopment of di-(8-hydroxyquinolene) Strontium (SrQ2)Polymer for Blue OLED ApplicationsI. M. Nagpure*, Kamla Nehru College, India

Now days there is constitute a rapid development in the field of Or-ganic light-emitting diodes (OLEDs)and Liquid Crystal Display(PLLCD) that many believe represents the future of flat panel displaytechnology. In this paper we have reported lumophores based onstrontium metallo-8-hydroxyquinolates, which have been prepared asOrganic light-emitting material, and their absorbance, photolumi-nescence and thermal properties were studied. SrQ2 were synthesizedby simple co-precipitation route producing a intense blue-emissionat 482nm under the excitation of 380nm and 422nm wavelength (ie.Blue OLED excitation wavelength). Prepared blended thin film ofmetal quinolene strontium complex of 8-hydroxyquinoline (SrQ2)solutions give PL emission in the range 480 to 485nm in blue regionof the visible spectrum.

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 213

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania214

4:20 PMOptical Properties of PhthalocyaninesS. K. Sikha*, G. Devrani, R. Rivero, N. M. Ravindra, New Jersey Institute ofTechnology, USA

Optical properties of phthalocyanines are summarized in this study.These properties are based on reported experimental data in the liter-ature. Correlations between optical properties and the band structureof phthalocyanines have been made utilizing phenomenological ap-proaches. An assessment of the various methods utilized to determinethe energy gap of phthalocyanines is made in this study. Detailedanalyses of the frequency dependent dielectric properties of phthalo-cyanines is presented.

4:40 PMCrystal cored fibers growth of organic non-linear optical materialR. N. Rai*, Banaras Hindu University, India

The crystal-cored fibers of organic material, pentachloropyridine(PCP), have been grown using the inverted Bridgman-Stockbargermethod. The optimized conditions for the good quality crystal coredfibers growth have been determined. Based on growth conditions,both, homogeneous and inhomogeneous crystal cored fibers weregrown and photographed. The suitable temperature profile for thegrowth of uniform crystal-cored fibers has been established. TheLaue technique has been used to verify the single crystal cored crys-talline nature of the fibers. Several properties of the PCP material,such as second harmonic generation (SHG) efficiency, range of trans-parency, and mechanical and thermal stability are found promisingfor applications.

Fundamentals & Characterization: PhaseStability, Diffusion Kinetics and TheirApplications (PSDK-III)

Thermodynamics and Phase StabilityRoom: 302Session Chairs: Sudarsanam Babu, The Ohio State University;Raymundo Arroyave, Texas A&M University

2:00 PMDesign of Engineering Materials based on ab initioThermodynamics and Kinetics (Invited)J. Neugebauer*, B. Grabowski, L. Ismer, T. Hickel, M. Friak, Max-Planck-Institut für Eisenforschung, Germany

The combination of accurate first principles calculations with meso-scopic/macroscopic thermodynamic and/or kinetic concepts hasquickly advanced in the past few years and allows now to tackle evencomplex engineering systems such as polycrystals or steels. Key tothese studies is the highly accurate determination of free energies andsurfaces. In the first part of the talk it will be shown how efficientsampling strategies together with high convergence density-func-tional theory calculations allow an accurate determination of all rele-vant temperature dependent free energy contributions such as elec-tronic, harmonic, anharmonic, magnetic and structural excitations.Based on these results and applying homogenization techniques thestability issues and mechanical properties of various alloys can becomputed.

2:40 PMAb Initio Investigation of the Finite-Temperature ThermodynamicProperties of Strontium SilicidesR. Arroyave*, Texas A&M University, USA; A. Garay, CINVESTAV - UnidadQuerataro , Mexico; M. E. Williams, Texas A&M University, USA; G. Trapaga,CINVESTAV - Unidad Querataro , Mexico

The thermodynamics of the Sr-Si system is of fundamental impor-tance for the understanding of eutectic modification of Al-Si alloys.

Renewed research efforts have led to a re-evaluation of the phaseequilibria in this system, resulting in the discovery of previously un-detected stable intermetallic compounds. Investigations on the ther-modynamics of this system have been somewhat limited in scope. Inthis work, we present some recent investigations on the finite temper-ature thermodynamic properties of the stable (and metastable) Sr-Siintermetallics. Electronic structure calculations are combined withquasi-harmonic lattice dynamics and simple electronic disorder ap-proximations to calculate the temperature-dependence of the ther-modynamic properties of these phases. The nature of structuralphase transitions observed in the SiSr2 composition will also be in-vestigated. The results from this work will later be used to develop afully consistent thermodynamic model for this binary.

3:40 PMPhase stability and selection in Al-Sm binary alloys (Invited)R. E. Napolitano*, Iowa State University, USA; S. H. Zhou, AmesLaboratory, USA

Issues of phase stability in the Al-Sm binary system are discussedwith respect to solidification, glass formation, and devitrification.Phase selection and nonequilibrium partitioning are investigated inrapidly solidified alloys produced by free-jet melt spinning. The rela-tive stability of Al11Sm3 (Al4Sm) intermetallic phases is examinedthrough a series of heat treatments followed by microstructural, mi-crochemical, and x-ray diffraction analyses. The results are incorpo-rated into a general solution-based model for the thermodynamicproperties and associated phase equilibria for the Al-Sm binary sys-tem. Employing an association model for the liquid phase, sublatticemodels for intermetallic phases, and a two-state model for the under-cooled liquid, both stable and metastable phase equilibria are pre-sented over the full composition range. Composition limits for solid-ification are presented using a Baker-Cahn analysis and results arecompared with experimental observations of phase selection andnonequilibrium partitioning.

4:20 PMApplication of Computational Thermodynamics and Kinetics toPredict Weld Microstructure EvolutionS. S. Babu*, Ohio State University, USA

Microstructure evolution during welding is complex due to interac-tions between phase transitions that occur in liquid, solidificationand solid-state transformations. This lecture will highlight variousphenomenological tools that has been created to describe the den-drite tip growth, solidification partitioning, reconstructive and dis-placive transformations in wide range of alloy systems. Tangible ex-amples of these microstructure prediction using computationalthermodynamic and diffusion controlled growth theory will bedemonstrated with examples from ferrous and non-ferrous alloys.The challenges in describing the non-equilibrium effects due to rapidcooling and external elastic strain conditions will be described. Therole of in-situ characterization techniques and local electrode atomprobe microscopy will be discussed.

4:40 PMDetermination of phase relations in the quaternary Fe-Ni-Ti-AlsystemL. I. Duarte*, C. Leinenbach, Empa, Swiss Federal Laboratories for MaterialsTesting and Research, Switzerland; U. E. Klotz, FEM, Research Institute forPrecious Metals and Metals Chemistry, Germany; J. F. Loeffler, ETH Zurich,Switzerland

Intermetallics, for example Fe-Ni-Ti aluminides, possess many attrac-tive structural and functional properties like high-temperaturestrength or hydrogen storage. However, most intermetallics appear tobe brittle and improving their ductility is crucial. To facilitate an effi-cient Fe-Ni-Ti aluminide alloy design, quantitative data on phase sta-bility and phase relations is required. Diffusion multiple technique isa useful tool for studying phase diagrams. The Fe-Ni-Ti-Al system is

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 214

Wed

nes

day

PM

www.matscitech.org 215

very difficult to investigate via standard diffusion multiple techniques,because the melting point of Al is much lower than the melting pointsof the other elements. In this study the quaternary Fe-Ni-Ti-Al systemwas investigated with special attention to the FeAl-NiAl-TiAl section.Diffusion multiples from single-phase intermetallics and individualalloys with selected compositions were prepared and annealed at1000°C. Microstructural characterisation was performed by SEM andchemical compositions were analysed by EPMA.

5:00 PMSubsolidus Phase Equilibria in the Zn-In-Sn-O and In-Ga-Zn-OSystemsS. P. Harvey, A. Adler*, K. R. Poeppelmeier, T. O. Mason, NorthwesternUniversity, USA

Subsolidus phase equilibria studies were made of the Zn-In-Sn-O(ZITO) system at 1275°C, of importance to Transparent ConductingOxides (TCOs) and Transparent Oxide Semiconductors (TOSs), andthe In-Ga-Zn-O (IGZO) system at 1350°C, of particular importanceto TOSs. Samples were prepared using conventional solid state syn-thesis and analyzed by X-ray diffraction. The ZITO system containstwo extended solid solutions: a zinc- and tin- co-substituted bixbyitephase and an indium-substituted zinc stannate spinel phase. In theIGZO system, our work builds upon that of Nakamura, et al.1, focus-ing on the gallia-rich portion of the diagram. The homologous seriesof compounds in the Zn-In-O system plays an important role in bothternary diagrams. These phases show extended solid solubility of gal-lium for indium in the IGZO ternary. Ramifications for electronicand optoelectronic applications of the various phases in these twosystems will also be discussed. [1] Nakamura, et al., J. of S.S. Chem.,93, 298-315, 1991.

5:20 PMSolvus boundaries of metastable phases in Al-Mg-Si system: First-principles phonon calculations and thermodynamic modelingH. Zhang*, Y. Wang, S. Shang, The Pennsylvania State University, USA; C.Wolverton, Northwestern University, USA; L. Chen, Z. Liu, The PennsylvaniaState University, USA

Due to the complexity of the precipitation sequence in Al-Mg-Si al-loys, the metastable phase solvus boundaries are very difficult to as-certain experimentally. In present work, using first-principlesphonon approach, the thermodynamic properties including forma-tion enthalpies and vibrational entropies have been predicted forthree phases: the stable β-Mg2Si, the metastable β’-Mg18Si10 and β’’-Mg5Si6. The stable soluvs boundary of fcc/β and the metastable soluvsboundaries of fcc/β’ and fcc/β’’ are therefore calculated via the CAL-PHAD technique, which agree well with the available measurementsof phase boundaries. This work demonstrates how first-principlescalculations can be used to predict precipitate phase boundaries ofstable and metastable phases, and the presently predicted solvusboundaries provide helpful insights into understanding the processesof age hardening of Al-Mg-Si alloys.

5:40 PMThermodynamic Evaluation of the Mg-Y-Ni Ternary SystemM. Islam*, M. Medraj, Concordia University, Canada

Thermodynamic modeling of the Mg-Y-Ni system is carried out as apart of multicomponent thermodynamic database for Mg alloys. Thissystem is being modeled for the first time using the modified quasi-chemical model which considers the presence of short range orderingin the liquid. A self-consistent thermodynamic data base for this sys-tem is constructed by combining the thermodynamic descriptions ofthe constituent binaries. Mg-Ni and Y-Ni binary systems have beenre-optimized based on the experimental phase equilibrium and ther-modynamic data available in the literature. The optimized thermody-namic parameters for the Mg-Y system are taken from the previousthermodynamic assessment on the Mg-Cu-Y system by the same au-thors. The constructed database is used to calculate and predict ther-

modynamic properties, binary phase diagrams and liquidus projec-tion of the ternary Mg-Y-Ni system. The calculated results are foundto be in good agreement with the experimental data reported in theliterature.

Fundamentals & Characterization: RecentAdvances in Structural Characterization ofMaterials

Electron Microscopy and Electron Diffraction:Developments and Applications IRoom: 309Session Chairs: Xiaoli Tan, Iowa State University; Ian Reaney,University of Sheffield

2:00 PMObserving Nanosecond Phenomena at the Nanoscale with theDynamic Transmission Electron Microscope (Invited)G. H. Campbell*, N. D. Browning, J. S. Kim, T. LaGrange, B. W. Reed, M. L.Taheri, Lawrence Livermore National Lab, USA

The dynamic transmission electron microscope (DTEM) is a TEMthat has been modified to operate with a single intense pulse of elec-trons (>108 e–) with pulse duration of 15 ns. The short pulse of elec-trons is created via photoemission at the cathode. The DTEM hasbeen used to investigate a number of rapid phenomena in materials.It has characterized the rate of the martensitic transformation of Ti asit transforms from α to β phase at elevated temperature. The datahave created the first time-temperature-transformation (TTT) dia-gram with nanosecond time resolution and have illuminated a mech-anism changes that depends on temperature. DTEM has also beenused to study reactive multilayer films that sustain a reaction frontspeed greater than 10 m/s. A transient cellular morphology to the re-action front was identified. Work performed under the auspices ofthe US Dept. of Energy, Office of Basic Energy Sciences by LawrenceLivermore National Lab under contract DE-AC52-07NA27344.

2:40 PMMicrocharacterization of CF8C-Plus and CF8C-Plus+Cu/W AlloysRequired to Explain High Temperature Strength and CreepPropertiesN. D. Evans*, P. J. Maziasz, J. P. Shingledecker, Oak Ridge NationalLaboratory, USA; M. J. Pollard, Caterpillar Inc., USA

CF8C-Plus cast austenitic stainless steel (Fe-19.5Cr-12.5Ni-0.08C-0.8Nb-0.45Si-4Mn-0.25N; Wt%) and CF8C-Plus+Cu/W (with 3Cu,1W added) are new cost-effective creep resistant alloys. This presen-tation will describe how advanced electron imaging and analysistechniques (low-voltage SEM image signal mixing, simultaneousdrift-corrected EDS and EELS spectrum mapping, selected area andconvergent beam diffraction experiments, and statistical analysis oflarge data sets) were employed to characterize the inherently complexand nano-scale features which develop in these alloys during high-temperature exposure or creep-rupture testing. Research sponsoredby Propulsion Materials Program, DOE/EERE Office of Vehicle Tech-nologies, and at the ORNL SHaRE User Facility by the Division ofScientific User Facilities, Office of Basic Energy Sciences, under con-tract DE-AC05-00R22725 with UT-Battelle, LLC.

3:00 PMRevealing local structural disorder and inhomogeneity usingquantitative electron microscopy (Invited)Y. Zhu*, BNL, USA

Electrons, neutrons and photons are three complementary probes formaterial structure-characterization. The advantage of the electronprobe is its strong interaction with matter and its small beam size that

001_271.MST_Abstract.4th 9/3/08 3:08 PM Page 215

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania216

allow us to reveal local disorder and inhomogeneity of crystal struc-ture, electronic structure, and chemical composition of a material. Inthis presentation we report our recent integrated studies, using state-of-the-art quantitative electron diffraction, atomic imaging, EELS,and electron holography as well as single-crystal x-ray diffraction,EXAFS and DFT calculations, to understand exotic physical behaviorof various transition-metal-oxides including dielectric CaCu3Ti4O12and mixed-valent manganites (Re1-xAxMnO3) that exhibit CMR ef-fects. The merit and drawback of the methods will be discussed. Sup-ported by U.S. DOE under contract No. DE-AC02-98CH10886. Col-laborations with L. Wu, J. He, M. Schofield, J.C. Zheng, A.I. Frenkel, J.Hanson and Ch. Jooss are acknowledged.

4:00 PMTomographic reconstruction of the magnetic vector potential of amagnetic nano-particle by means of Lorentz transmission electronmicroscopyC. Phatak, Carnegie Mellon University, USA; M. Tanase, A. K. Petford-Long,Argonne National Laboratory, USA; M. De Graef*, Carnegie MellonUniversity, USA

Lorentz TEM combined with phase reconstruction methods can beused to acquire tomographic data sets for the full 3-D characteriza-tion of magnetic nano-particles. In this contribution we will describehow the data can be acquired in the form of through-focus image se-ries, and how those series can be used subsequently to reconstruct ei-ther the magnetic induction or the magnetic vector potential in andaround the object. We will illustrate the procedure using experimen-tal data acquired on a Tecnai F20 Lorentz TEM, and we will discusshow the use of a spherical aberration corrector may significantly im-prove the spatial resolution of the tomographic reconstructions. Wewill also describe the sources of error contributing to the uncertaintyof the reconstructed fields. Experimental reconstructions will becompared with numerical models of the magnetic vector potentialfor square permalloy islands.

4:20 PMHREM Studies on Nano-scale Pt Catalysts Supported on γγ-Al2O3L. Li*, Z. Zhang, University of Pittsburgh, USA; J. H. Kang, S. I. Sanchez,University of Illinois at Urbana-Champaign, USA; Q. Wang, YeshivaUniversity, USA; L. Wang, D. D. Johnson, University of Illinois at Urbana-Champaign, USA; A. I. Frenkel, Yeshiva University, USA; R. G. Nuzzo,University of Illinois at Urbana-Champaign, USA; J. C. Yang, University ofPittsburgh, USA

In heterogeneous catalysis, the electronic landscape controlling thesurface chemistry depends intimately on the 3-dimensional atomicarrangement of the supported metallic nanoparticles (NPs) and theNP/support interactions. We examined Pt NPs with 1 nm, 1.5 nm and2.9 nm diameters supported on γ-Al2O3, by high-resolution transmis-sion electron microscopy (HREM)and high-angle annular dark-fieldimaging (HAADF). We noted that the crystallinity of the Pt particlesis size-dependent. The Pt NPs with diameters larger than 3 nmshowed well-ordered fcc structure, a=0.39 nm, where some particlescontained twin boundaries. In contrast, the 1 nm or smaller Pt parti-cles did not show clear evidence for crystallinity. This lack of uniformbond-lengths and ordered arrangement of Pt atoms is supported byX-ray Absorption Spectroscopy(XAS)and theoretical simulations.Misorientation of Pt NPs with their support was frequently observedfrom crystalline Pt NPs (>3 nm), suggesting that Pt NP/support in-teraction is not strong.

4:40 PMIn-situ UHV-TEM study of the reduction of surface oxide islandsG. Zhou*, State University of New York, Binghamton, USA; J. C. Yang,University of Pittsburgh, USA

The reduction of metal oxides is important for many industrial appli-cations. Traditionally, the reduction process has been described usingphenomenological kinetic models (e.g., “nucleation and growth

model” and “interface model”) where the reduced oxide nucleatesand grows on the oxide surface. Although these models have beenfound useful in the description of the reduction of oxide single crys-tals and particles, here we show using in situ ultra-high vacuum(UHV)-TEM that they do not apply to the reduction of surface oxideislands. Our in situ TEM observations reveal that the reduction ofCu2O islands on Cu(100) is accompanied by the growth of the re-duced phase on the substrate surface, rather than on the parent oxide;this is fundamentally different from the assumption by the phenome-nological models. We show that the reduction of these oxide islandsleads to the formation of surface craters and the growth of the craterrim is controlled by the homoepitaxy of Cu atoms dislodged from thereducing Cu2O islands.

5:00 PMExperimental Investigations on Nitrides Stability in a12CrWMoVNb SteelF. Mendez Martin*, M. Albu, B. Sonderegger, G. Kothleitner, Graz Universityof Technology, Austria

The advanced operating conditions for steam power plants requirematerials with higher steam oxidation resistance and creep strengthand 9 – 12% Cr martensitic steels are excellent candidates. The creepresistance of these steels is due to the formation and interaction ofdifferent precipitate populations like NbC, VN, Cr2N, M23C6, Lavesphase and modified Z-phase, but changes in microstructure lead to areduction of the creep strength of the steel. In this work, the growth,coarsening and dissolution of precipitates during service exposurehave been identified by elemental mapping techniques in transmis-sion electron microscopy (TEM) and diffraction methods in a 12Cr-WMoVNb steel. The formation of mod. Z-phase at expense of VN in-volve that the main strengthening mechanism (precipitatestrengthening by MX (VN) particles) of this steel is “dissolved”. How-ever, a larger stability of Cr2N phase vs. MX (VN) indicates the possi-bility to use this nitride as main precipitate strengthening phase.

5:20 PMCompositional Characterisation of Secondary Carbides andComplex Nitrides in Chromium SteelsM. Albu*, F. Mendez Martin, G. Kothleitner, Graz University of Technology,Austria

Chemical composition of different secondary carbides and complexnitrides in 9–12 % chromium steels was obtained by using electronenergy loss spectroscopy. A method based on multiple linear leastsquares fit deconvolution was applied to extract the edge intensities,fitting suitable references to all overlapping edges. Computing the rel-ative fit weights and integrating the references over an energy range of100 eV, allows calculation of the atomic percentages of each element,provided experimentally determined cross-sections are available. Viathis route, secondary carbides with closed chemical composition andrather similar crystallography, as well as, different metastable nitridephases transforming directly or due to nitrogen diffusion into modi-fied Z-phases have been identified. The results, augmented by X-rayspectroscopic data and electron diffraction, show a good agreementcomparing with the outcomes of the thermodynamic model imple-mented in the software package MatCalc.

5:40 PM3D-TEM characterization of metal nanoparticle-dispersedamorphous SiO compositeY. H. Ikuhara*, K. Yoshida, T. Saito, S. Takahashi, T. Hirayama, Japan FineCeramics Center, Japan

It has been known that metallic nanoparticle is effective to improvethe properties of amorphous silica by forming the metal nanoparti-cle-dispersed silica based composite. For example, Ni nanoparticleswhose size is less than 10nm enhances the hydrogen permeation effi-ciency in amorphous silica membrane. But, the atomistic mecha-nism for the permeation kinetics has not been well understood. In

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 216

Wed

nes

day

PM

www.matscitech.org 217

order to understand the mechanism, the microstructures are neededto be characterized with an atomic scale. In this study, high resolu-tion electron microscopy has been applied to investigate the inter-face between Ni nanoparticles and the matrix. In addition, highangle annular dark field STEM (HAADF-STEM) was applied tocharacterize the distribution of the nanoparticles in the matrix.Concerning the HAADF-STEM observations, we used 3-D projec-tion technique in addition to the ordinal 2D projection observationsto quantitatively measure the size and the distribution of thenanoparticles.

Fundamentals & Characterization: The Effectof Electrical (and Electromagnetic) Fields andStress (and Capillarity) on DiffusionalTransport in Ceramics and RelatedPhenomena

Enhanced SinteringRoom: 311Session Chair: Rishi Raj, University of Colorado

2:00 PMThe Absence of Plasma in “Spark Plasma Sintering” (Invited)D. M. Hulbert, D. V. Dudina, D. Jiang, C. Unuvar, U. Anselmi Tamburini, E. J.Lavernia, A. K. Mukherjee*, University of California, USA; A. Anders, J.Andersson, Lawrence Berkeley National Lab, USA

Spark plasma sintering (SPS) is a remarkable method for synthe-sizing and consolidating a large variety of both novel and tradi-tional materials. The process typically uses moderate uni-axialpressures (< 100 MPa) in conjunction with a pulsing on-off DCcurrent during operation. There are a number of mechanismsproposed to account for the enhanced sintering abilities of theSPS process. Of these mechanisms, the one most commonly putforth and the one that draws the most controversy involves thepresence of momentary plasma generated between particles. Thisstudy employs three separate experimental methods in an attemptto determine the presence or absence of plasma during SPS. Themethods employed include: in-situ atomic emission spectroscopy,direct visual observation, and ultra-fast in-situ voltage measure-ments. It was found using these experimental techniques that noplasma is present during the SPS process. This result was con-firmed using several different powders across a wide spectrum ofSPS conditions.

2:40 PMEffect of Pulsed DC Current and Electric Field on the Growth ofCarbide Ceramics during SPST. Kondo*, T. Kuramoto, M. YAsumasa, Y. Kodera, M. Ohyanagi, RyukokuUniv., Japan; Z. A. Munir, University of California , USA

The influence of pulsed DC current and electric field on the growthof TiC and ZrC layers using Spark Plasma Sintering was investigatedat the temperature ranging from 1373 to 1823K. From the result ofXRD analysis, the product layer formed between Ti and C was onlyTiC, and that formed between Zr and C was also only ZrC, respec-tively. In all system, the thickness and the growth rate constant ofproduct layers were enhanced in the presence of the current com-pared with the absence of the current. The activation energy for thegrowth of TiC layer was calculated to be 269±3 kJ/mol in the presenceof the current, which was smaller than the that of 273±2 kJ/mol in theabsence of the current. In case of Zr-C system, these were 205±7kJ/mol and 224±1 kJ/mol, respectively. The increase in growth of TiCand ZrC layers was unaffected by the direction of the current and im-plied that the electron wind force was not a dominant cause of the en-hanced growth.

3:00 PMField-Assisted Acceleration of Diffusion in Spark-Plasma andMicrowave Sintering (Invited)E. Olevsky*, San Diego State University, USA

The difference in outcomes of field-assisted sintering and conven-tional powder hot consolidation techniques can be attributed to thetwo groups of physical phenomena: of thermal and of non-thermalnature. The first group may include high heating rates, which enablehigher sinterability; high local temperature gradients, which provideconditions for thermal diffusion; highly non-uniform local tempera-ture distributions, which may cause melting within inter-particlecontacts; highly non-uniform macroscopic temperature distribu-tions, which create thermal stresses intensifying dislocation creep.The second group may include electromigration and intensified dif-fusion in ionic conductors; electroplasticity mechanisms; pondero-motive forces; electromagnetic “pinch” effect; dielectric breakdownof oxide films and defect generation at grain boundaries. The discus-sion emphasizing major thermal and non-thermal phenomena con-tributing to the material transport in field-assisted sintering will bepresented.

Iron & Steel: Refractory Innovations andNovel Applications in Iron & SteelManufacture

Refractories for Iron and Steel IIRoom: 329Session Chair: Mike Alexander, Riverside Refractories, Inc.

2:00 PMA New Temperature Independent Cement for Low and Ultra LowCement CastablesD. Zacherl*, Almatis, INC, USA; A. Buhr, D. Gierisch, H. Gross, AlmatisGmbH, Germany; F. Kraaijenbos, G. Wams, Almatis B. V., Netherlands

Low and ultra low cement castables are widely used for in-situ in-stallations and for the manufacturing of pre-cast shapes. High alu-mina calcium aluminate cements are a key component of these for-mulations, although they are only added in small amounts. It ispossible to adjust the setting times of low and ultra low cementcastables according to the requirements of the final application.When using consistent high quality cement and additives such asdispersing aluminas, the setting behavior of castables can also betailored to different temperature conditions. However, for a givenmix composition, the setting time can change significantly if theambient temperature is outside the expected range. A new, additivefree 70% alumina cement CA-470 TI has been developed to signif-icantly reduce the setting time variations at different ambient tem-peratures. It is intended specifically for castables with low or ultralow cement content using dispersing systems, without or with sil-ica fume.

2:20 PMCharacterization of Silica Fume by Dynamic Viscosity andThermal Gravimetric AnalysisB. G. Self*, Reno Refractories, Inc., USA

The purpose of the study is to create a practical method for the deter-mination of the overall quality of silica fume. The method takes ad-vantage of the unique properties of the material: particle size, insolu-bility, and impurities. The test repeatedly revealed the significantdifferences between the various manufacturers. Results showed astrong correlation between free carbon and silicon content and ap-parent dynamic viscosity. We concluded that the dispersal of silicafume in water may ultimately depend upon the effect impurities haveon the surface charge acquired in the densification process.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 217

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania218

2:40 PMSolid Solution Effects on Thermal ConductivityK. OHara*, J. Smith, Missouri University of Science and Technology, USA; J.Hemrick, Oak Ridge National Laboratory, USA

Thermal conductivity is of interest for ceramics, particularly in re-fractory applications to increase energy efficiency. Lowering the effec-tive thermal conductivity can be accomplished by adding porosity, se-lection of different materials and utilization of smaller grain size. Theeffect of solid solution has also been of interest, however, a systematicstudy in refractory materials has not been conducted. The mecha-nisms that control thermal conduction as a function of temperaturewill be provided with attention to low temperatures. A study of thethermal conductivity of spinel based materials and the impact ofsolid solutions with numerous oxides (FeO, Cr2O3, and ZnO) havebeen studied. Data including onset formation temperatures, reactionkinetics, and degree of solid solution achieved indicate the ease of ap-plying this approach in industry. Data will be provided relating tothermal conductivity as a function of temperature and degree of solidsolution and a model will be provided to predict thermal conductiv-ity reductions.

3:40 PMNewly-Developed Technique in Evaluation of Resistance to SlagCorrosion for Refractory at High TemperatureH. Sunayama*, T. Hiroi, M. Kawahara, Kumamoto University, Japan

The experimental apparatus was assembled from three resistance fur-naces, which were named the upper, the middle and the lower fur-nace. The refractory specimens, which were alumina-chrome andmagnesia-carbon refractories, were placed in the middle furnace. Thespecimen had a cylindrical hole of 20 mm in diameter and of 150 mmin length. The molten slag flowed through a hole at the bottom of theslag reservoir, and then flowed through the cylindrical hole in thespecimen. The temperature was in the range of 1673 to 1823 K. Theincrease of the diameter of the hole was measured to evaluate the cor-rosion resistance. The structure of the specimen was observed with anoptical microscope and a SEM. Furthermore, EPMA analysis wasconducted for the specimen after the corrosion test. Much new infor-mation about the corrosion mechanism of the refractories was ob-tained by the newly-developed technique.

4:00 PMComparison of thermal shock testing between a direct electricalheating method and a water-quenching method with carbon-containing refractoriesS. Hosohara*, Y. Fukushima, Y. Kiyota, M. Iiyama, JFE Steel Corporation, Japan;S. Honda, S. Hashimoto, H. Awaji, Nagoya Institute of Technology, Japan

Thermal shock resistances of carbon-containing refractories wereevaluated by a direct electrical heating (DEH) method. This methodwhich has relatively larger heat flux than the other thermal shock test-ing is applicable to electro-conductive materials. In this study, theDEH method was improved by using the thermal stress analysis andthermal shock parameters of infrared radiation heating method. Oc-currence and propagation of fracture were detected using acousticemission and used in the analysis of determination of critical thermalstress. It was found that the thermal shock parameters obtained canbe used to evaluate the thermal shock resistance of carbon-contain-ing refractories. Several specimens, however, did not fracture due toinsufficient heat flux depending upon the resistivity of the materials.The thermal shock strength and thermal shock fracture toughnesstended to increase with the carbon contents of the specimens.

4:20 PMA Study on the Interfacial Oxygen Behavior in Molten Steel byElectrochemical Method Using ZrO2 based Solid ElectrolyteW. Kim*, D. Min, YONSEI university, South Korea

Currently, the interfacial reaction between refractory and molten steelplays a controlling factor to manufacture the ultra clean steel. The

current researches on inclusion formation and surface tension at theinterface suggested the strong evidences that interfacial reaction couldbe suppressed by controlling the surfactive oxygen on interface ofmolten steel. Among the methodologies for control the oxygen poten-tial at interface, electrochemical technique has been applied to directde-oxidation without deoxidizer such as Al, Mn, Si. Experimental re-sults indicate that the rate of electrochemical de-oxidation was con-trolled by diffusion of oxygen in molten steel. The concentration ofoxygen in boundary layer was confirmed by GDS and SIMS. The oxy-gen deplete layer due to slow diffusion rate of oxygen toward the in-terface through the boundary layer. The oxygen concentration wascontrolled to 10ppm level at the interface by applying external voltage.

Iron & Steel: Steel Product Metallurgy andApplications

Microstructure - Property Correlations IIIRoom: 330Session Chair: John Paules, Ellwood Materials Technologies

2:00 PMInfluence of the Epsilon Phase Transition on Microstructure andDynamic Shear Behavior of 1018 SteelL. M. Dougherty*, E. K. Cerreta, G. T. Gray, C. P. Trujillo, Los AlamosNational Laboratory, USA

When impacted at pressures exceeding 13GPa, the ferrite in 1018 steelundergoes a fully-reversible transition from the alpha to the epsilonphase. In this study, specimens of 1018 steel were shock-loaded at arange of pressures from below to well above the epsilon phase transi-tion pressure, both in a gas gun apparatus and with explosives. At thelower pressures, the ferrite did not experience the epsilon phase tran-sition, whereas, at the higher pressures, complete transition throughthe epsilon phase is believed to have transpired. The resultant mi-crostructures were compared using a suite of microstructural charac-terization techniques to understand the impact of the epsilon phasetransition on the microstructure of the alpha phase following rever-sion. Then, using a split-Hopkinson pressure bar apparatus, the dy-namic shear behavior of these shocked specimens was studied to de-termine the effect of the epsilon phase transition on the dynamicshear performance of 1018 steel.

2:20 PMThe Effect of Nickel Content on 4330 Steel with Regard toMicrostructure and Grain Growth CharacterizationE. A. Bilitz*, IIT, USA; G. Brada, A. Finkel & Sons, USA; P. Nash, IIT, USA

4330 alloy steel is a non-regulated composition with varying weightpercent nickel content based on final application. The amount ofnickel alloying addition in 4330 steels can have adverse affect on themicrostructure upon high temperature compression. The researchconducted seeks to show a relationship between forge temperatureand nickel percent through grain growth and microstructural charac-terization through SEM. Creating awareness of the relationship willhelp prevent overheating and burning in steel forgings.

2:40 PMThermo-metallurgical model of the run out table and coilerapplied to Ternium SiderarG. R. Gomez, J. Schich, M. A. Vicente Alvarez*, F. Balzarotti, Tenaris SidercaR&D, Argentina; S. Moriconi, Ternium, Argentina; M. Goldschmidt, T. E.Perez, Tenaris Siderca R&D, Argentina

A coupled thermo-metallurgical model was developed to predict themechanical properties of hot rolled steel strips all along the coillength. The thermal finite element (FE) model solves the heat diffu-sion equation considering the transformation enthalpy produced bythe austenite decomposition. In the run out table, the thermal modelevaluates the temperature evolution considering the heat extraction

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 218

Wed

nes

day

PM

www.matscitech.org 219

due to the water sprays. The metallurgical model calculates the ki-netic of austenite decomposition and evaluates the transformationenthalpy. It also predicts the grain size, pearlite laminar spacing andprecipitation of elements in solid solution. The predictions of thecoupled model were compared with temperature measurements atthe end of the run out table (coiling temperature) for C-Mn and mi-croalloyed steels with excellent agreement. Moreover the predictedyield strength and ultimate tensile strength had a good agreementwith the measured ones.

3:40 PMThe Influence Of Chemical Composition, Heat Treatment AndMicrostructure On Fracture Behaviour Of Three Pressure VesselSteels In “Wet H2S” EnvironmentG. Chiofalo*, E. Guglielmino, Università di Messina, Italy; V. Gazzotti,Raffineria di Milazzo, Italy

In this paper an assessment of the effect of heat treatment and mi-crostructure on the behaviour of carbon steel in wet H2S environ-ment has been made. The investigation involved three ASTM A 516gr.70 steels. Two HIC Resistant steels, and a common pressure vesselsteel, without any HIC resistant requirement. HIC and SOHIC tests,according to NACE TM 0284 and TM 0103 has been conduced bothon base metal and welded samples, in delivery condition and after asimulated PWHT. Moreover, an assessment on toughness, by mean ofCTOD tests, has been made on samples after different exposure timein NACE TM 0284 test solution A, to derive the trend of CTOD valuesas a function of the exposure time, on both base metal and weldedsample. The results have been discussed in relation with the micro-graphic analysis of microstructure and non metallic inclusion beforeand after the heat treatments, for different materials.

4:00 PMMicrostrucuture and tensile behavior of metastable austeniticsteels with high Mn contentD. Suh*, S. Park, S. Kim, Korea Institute of Materials Science, South Korea

Grain refinement from a reverse transformation of martensite was re-ported to be useful for the improvement of mechanical properties ofsheet steels with a metastable austenitic structure. However, a wideapplication has been limited due to a considerable amount of Ni orCr. In this study, we attempted to develop a new advanced highstrength cold-rolled steels using the reverse transformation based onalloy system without Ni or Cr. For Fe-C-Mn steels, the fully marten-sitic structure obtained by cold-rolling was austenitized around Ae3temperature. Annealing just above Ae3 temperature ensured the sta-bility of austenite and nearly austenitic single structure could be at-tained for 0.1C-13Mn steel. It was confirmed that a tensile strengthabove 1300MPa with total elongation over 25% could be achievedowing to the strain-induced martensitic transformation ofmetastable austenite, and the characteristic work hardening of an-nealed steels was controlled by mechanical stability of austenite.

4:20 PMSteels for Large Plastic Moulds: Microstructures Arising duringthe Production CycleM. Pinasco, D. Firrao*, M. Fabbreschi, P. Matteis, B. Rivolta, R. Gerosa, A.Ghedini, University of Genoa, Italy

The study carried out on 40CrMnNiMo8-6-4 steel, high hardenabil-ity, low-alloy steel most commonly used in large plastic moulds pro-duction, concluded that, owing to the large size of the bloom, heat-treatments induce various cooling rates from surface to core resultingin different microstructures and mechanical properties from zone tozone. As an alternative, a 0.25% carbon low-alloy steel with 0.6% Moand V, Nb, Zr, B microalloyed was studied to achieve more uniformmicrostructures and properties throughout the bloom sections. Thisone shows, after quenching and tempering, a uniform microstructureat all depths. Moreover, the mechanical properties are essentially con-stant from surface to core of the bloom and are slightly improved.

The study involved the metallographic optical and SEM characterisa-tion, EDS maps, hardness and microhardness measures in order toidentify the different phases, their morphology and distribution andany solid solution composition heterogeneity.

4:40 PMEffects of TMCP conditions on tensile strength decrease of780MPa grade steels by PWHTJ. Shimamura*, M. Okatsu, N. Ishikawa, S. Endo, N. Shikanai, JFE SteelCorporation, Japan

Demand for the structural pipes for riser and conductor casing appli-cation has been increasing because of active development of subma-rine oil and gas field. As the oil and gas field becomes deeper, need forhigher strength pipes, such as API X80 and X100, are increased. Onthe other hand, since the PWHT (Post weld heat treatment) is gener-ally applied after welding, it is quite important for the higher strengthpipes to prevent strength decrease by PWHT. In this study, mi-crostructure control techniques for preventing strength decrease byPWHT was investigated. Precipitation hardening technique instead oftransformation hardening was developed in order to prevent PWHTsoftening of high strength steels. The effects of TMCP (Thermo me-chanical control process) conditions and chemistries of steel on themechanical properties before and after PWHT were investigated. Themicrostructural factors, such as bainite microstructure, dislocationstructure and precipitation, were discussed in this paper.

Materials & Systems: Advances in Biomedicaland Biomimetic Materials

Bioceramics IRoom: 333Session Chairs: Ryan Roeder, University of Notre Dame; JohnNychka, University of Alberta

2:00 PMHydroxyapatite Whisker Reinforced Polyaryletherketone forOrthopaedic and Spinal Implants (Invited)G. L. Converse, R. J. Kane, T. L. Conrad, N. Yanchak, University of NotreDame, USA; S. M. Smith, North Central Neurosurgery, Inc., USA; R. K.Roeder*, University of Notre Dame, USA

Hydroxyapatite (HA) whisker reinforced polymer biocompositesoffer a robust system to engineer biomaterials with tailored mechani-cal, biological and surgical function for synthetic bone substitutesand scaffolds. The elastic modulus, elastic anisotropy and ultimatetensile strength of polyaryletherketones (PAEK) were tailored tomimic human cortical bone using various levels of HA whiskers witha preferred orientation induced during processing. HA whisker rein-forced PAEK scaffolds with 75-90% porosity and up to 40 vol% HAwhisker reinforcement were also processed such that with HAwhiskers were embedded within the polymer struts to act as rein-forcement and exposed on the surface of polymer struts to promoteprotein/cell/tissue adhesion. The apparent compressive modulus andyield strength were tailored to mimic human vertebral trabecularbone. Finally, HA whisker reinforced PAEK interbody spinal fusioncages comprising a dense outer shell surrounding a porous scaffoldwere prepared.

2:20 PMEffect of crystallinity on mechanical properties and dissolution ofbioactive glass (Invited)J. A. Nychka*, University of Alberta, Canada; D. Li, F. Yang, University ofKentucky, USA

The processing history of bioactive ceramics greatly affects their per-formance. We have shown in previous studies that amorphous bioac-tive glass is affected by residual stresses, both in fracture behaviour anddissolution rate in vitro. As was shown in the early history of bioactive

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 219

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania220

glass by Hench et al., heat treating bioactive glass powders can result insurface crystallization, and in turn, the degree of crystallinity, whichcan delay the time to formation of apatite mineral layers on bioactiveglass. This study focuses on the comparison in behaviour betweenamorphous and crystalline bioactive glass 45S5 when the material isunder residual stress. The indentation hardness, fracture propertiesand the in vitro dissolution rate are monitored and contrasted be-tween bioactive glasses in different degrees of crystallinity.

2:40 PMSimultaneous Enhancements in the Hardness and Toughness ofNanocrystalline Hydroxyapatite (Invited)J. Wang, L. Shaw*, University of Connecticut, USA

It is well known that most materials exhibit an increased hardnessand decreased toughness as the size of nano-grains decreases. In thisstudy, we demonstrate that simultaneous improvements in bothhardness and toughness are possible for nanocrystalline hydroxyap-atite (HA) through a novel sintering procedure. Nanocrystalline HAbodies with an average grain size as low as 70 nm and a relative den-sity of 99.4% have been sintered via morphology-enhanced low tem-perature sintering. It is shown that the microhardness of HA followsthe Hall-Petch relationship for the entire grain size range studiedfrom sub-micrometers to nanometers. In the same grain size range,the indentation toughness of HA increases by as mush as 80% as thegrain size decreases from sub-micrometers to nanometers. The studyof the fracture path reveals that the improvement in the toughness isdue to a transition from transgranular cracking to intergranularcracking as the grain size decreases.

3:40 PMNovel Nanocomposites for Bone Regeneration (Invited)A. P. Tomsia*, E. Munch, J. Franco, P. Hunger, E. Saiz, Lawrence BerkeleyLab, USA

Different approaches for the fabrication of porous scaffolds for bonetissue engineering are described. In particular we will compare twonovel techniques for the fabrication of materials with complexporosities: robocasting and freeze casting. In robocasting the com-puter-guided deposition of ceramic and polymer-ceramic suspen-sions is used to build inorganic and hybrid materials with designedthree dimensional (3-D) geometries and microstructures. Freezecasting uses the controlled freezing of ceramic suspensions to formporous lamellar structures that exhibit compressive strengths muchlarger than materials with similar porosities prepared by conventionaltechniques. The microstructure of freeze-casted materials can be ma-nipulated by controlling the freezing kinetics and the composition ofthe suspensions. We will discuss how these techniques can be ex-tended to the fabrication of complex hybrid materials with uniquecombination of mechanical properties similar to those observed innatural composites such as bone or nacre.

4:00 PMNanocrystalline Titania Bioceramic doped with Metal Ions(Invited)S. J. Kalita*, A. K. Menon, University of Central Florida, USA

Nanocrystalline TiO2 has exhibited improved osteoblast activities.Hypothesis is, its properties can be improved by producing powderin the lower end of the nano-realm, controlling powder character-istics, and doping. We synthesized 5-12 nm TiO2 powder, and stud-ied influences of selective dopants on sintering, densification,hardness, flexural strength, bioactivity & biodegradation. TiO2powder was obtained by hydrolyzing titanium tetraisopropoxide ina mixture of isopropanol and water, after calcination at 400°C. Itwas doped with Mg, Zn & Si, uniaxially compacted and sintered at1100-1600°C in air. The powder and structures were characterizedusing XRD, SEM, HR-TEM, RS & DSC/TGA. Bioactivity &biodegradation were assessed in simulated body fluid. The dopantsrefined the microstructure and improved densification, hardness

and flexural strength. Mg doping showed the highest density of3.87(±0.14) g.cm-3, while Zn doping exhibited the highest hard-ness of 502(±9) HV. Flexural strength of 128(±7) MPa wasachieved.

4:20 PMMicrowave Processing of Dental PorcelainJ. Jokisaari, Clemson University, USA; S. B. Bhaduri*, The University ofToledo, USA; J. R. Mackert, Medical College of Georgia, USA

Microwave processing is an attractive method to densify dentalporcelains. The enhanced kinetics of densification make it simple tofabricate porcelain in clinics and dental laboratories. The objectivewas to examine the feasibility of using microwaves for firing dentalporcelains. A major phase in these materials is leucite, and it was im-portant to ensure that leucite absorbs microwaves. The extent of ab-sorption by the porcelains was tested by high temperature dielectricproperty measurements. Samples were prepared for microwave andconventionally-fired groups. A semi-industrial scale microwave fur-nace, operating at 2.45 GHz with an SiC susceptor were utilized.From dielectric measurements, it was seen that pure leucite and den-tal porcelains absorb microwaves. Density measurements indicatedno statistically significant difference in density between the twogroups after processing. Biaxial strength also showed no significantdifferences. The results demonstrate that microwave processing is ef-fective for dental ceramics.

4:40 PMSurface Modification of Hydroxyapatite: A Review (Invited)O. C. Wilson*, Catholic University , USA

Adsorption interactions with hydroxyapatite (HAp) play an integralrole in various processes that contribute to the birth, structural de-velopment, maintenance, and healing and remodeling of bone anddental tissue. The wide extent of its interactions in biological sys-tems has contributed to its utilization as a substrate for various ad-sorption and surface complexation events. Various molecules in-cluding natural and synthetic polymers, inorganic polymers,surfactants, pharmaceutical agents, and protein based adsorbentshave been used to modify the surface of HAp for applications rang-ing from improved colloid stability to enhanced bioactivity. Anoverview of HAp adsorption interactions will be presented in thistalk with a focus on fascinating applications in the area of bone in-spired nanocomposites.

5:00 PMBiotribologycal Characterization of the bilayer system: HA/ZrO2on 316LSSB. Bermúdez-Reyes, M. Contreras-García*, J. Zárate-Medina, I. Espitia-Cabrera, Universidad Michoacana de San Nicolás de Hidalgo, Mexico; J.Ortega –Saenz, M. Hernández-Rodríguez, Universidad Autónoma de NuevoLeón, Mexico; F. Espinoza-Beltrán, CINVESTAV, IPN, Mexico

Ortopeadic prosthesis, have to be highlly wear and physiological cor-rosion resistant.The bilayer system HA/ZrO2/316LSS is proponed inthis work because it presents very good physiological corrosion resist-ance. The hydroxiapatite coating was deposited by screen printing on316LSS previously covered by electrophoresis with a zirconia thinfilm and thermally treated at 650C for 5 min. The biotribologycalcharacterization was carried out on 316LSS hip heads and acetabularcups in a Hip Simulator FIME II equipment, using bovine fetal serum(SBF), as a lubricant. Scanning electron microscopy images were ob-tained at the beggining and at the end of the probe in order to observethe wear produced on the samples. EDS chemical analysis was alsoobtained. From the obtained results, the role of the hydroxiapatite asa solid lubricant was elucidated and it was concluded that the bilayersystem actually works efficiently protecting the 316L SS prosthesisunder extreme working conditions.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 220

Wed

nes

day

PM

www.matscitech.org 221

Materials & Systems: Enabling SurfaceCoating Systems: Science and Technology

Tribology CoatingsRoom: 335Session Chair: Pravansu Mohanty, University of Michigan

2:00 PMSynthesis and Tribological Behavior of MoS2-BasedNanostructured Films by High Power Pulse Ion Ablation (Invited)S. V. Prasad*, T. Renk, P. Kotula, Sandia National Laboratories, USA

Molybdenum disulfide-based nanostructured tribological filmswere synthesized by ablating dual-targets (alternating betweenMoS2 and Ti) with intense ion beams. Films were characterized byx-ray diffraction, Raman spectroscopy and transmission electronmicroscopy (TEM). Friction and wear measurements were madeusing a Si3N4 ball in dry nitrogen and humid air with 50% relativehumidity. Focused ion beam (FIB) microscopy was used to preparecross sections of wear scars suitable for characterizing friction–in-duced subsurface deformation in the nanostructured films. Sub-strate heating (to 300C) during deposition generated self assembledmolybdenum atoms into 50-100 nm size nanoboulders, and the ma-trix comprised of crystalline MoS2-Ti nanolaminates. The complexion-beam target interactions and the fundamental mechanisms gov-erning the self-diffusion of Mo atoms into crystalline nanostruc-tures to produce environmentally robust Tribological films will bediscussed.

2:40 PMNano-Engineered Encapsulated-Particles for the Creation of SelfLubricating Coatings and AlloysJ. Weyant*, A. Segall, I. Smid, T. Eden, Penn State, USA

The development of wear-resistant self-lubricating coatings has beena major topic of interest in recent years. Fabrication of such coatingsinvolves imbedding solid lubricant particles within metallic matrices,and would prove to be beneficial for high performance machines. De-position of nickel coated hexagonal boron nitride (hBN) via high ve-locity particle consolidation (cold spray) has been investigated as apossible self-lubricating coating for surfaces prone to fretting. Nickelcoatings ranging from 10-15μm have successfully been depositedonto 10μm hBN powder through an electroless nickel depositionprocedure. The fabricated powder has effectively been deposited ontoTi-6Al-4V substrates through cold spray deposition. Incorporation ofhBN particles within a nickel matrix have been characterized throughvarious methods and have been shown to reduce the coefficient offriction of the coating.

3:40 PMLow Temperature alpha-Alumina Coating by Laser ChemicalVapor Deposition (Invited)T. Goto*, T. Kimura, H. Kadokura, IMR, Tohoku Univ., Japan

Cutting tools are generally coated by alpha-Al2O3 film due to its highharness, low thermal conductivity and high-temperature stability.alpha-Al2O3 film can be prepared by thermal chemical vapor deposi-tion (CVD) using halide precursors above 1373K. However, the highprocess temperature often causes the degradation of cutting tools. Wehave developed laser CVD (LCVD) enabling many oxide films to pre-pare at high deposition rates several 100 to 1000 times greater thanthat of common CVD. In the present study, Al2O3 films have beenprepared by LCVD using aluminum acetylacetonate (Al(acac)3).With increasing deposition temperature (Tdep), gamma +theta,alpha+ theta and alpha+gamma phases appeared. Alpha-Al2O3 filmin a single phase was obtained at Tdep above 1140K. Significantly(300) or (006) oriented alpha-Al2O3 films were prepared. The high-est deposition rate of alpha-Al2O3 film was 310 micro m/h.

4:20 PMMicrotexture and Hardness of CVD Deposited αα-Al2O3 andTiCxN1-x CoatingsH. Chien*, M. C. Gao, H. M. Miller, G. S. Rohrer, Carnegie Mellon University,USA; Z. Ban, P. Prichard, Y. Liu, Kennametal Inc. , USA

The microstructures of chemical vapor deposited coatings on fourtool inserts have been comprehensively characterized using electronbackscatter diffraction mapping. Nanoindentation was used to meas-ure the hardness of the TiCxN1-x and α-Al2O3 layers in each coat-ing. Object oriented finite element analysis was used to simulate theresidual thermal stresses. The TiCxN1-x layers have weak [112] or[101] textures in the growth direction and are highly twinned. Thealumina layers have or [0001] textures in the growth direction thatare 4.2 to 8.8 times random. The hardest coatings consist of highlytwinned TiCxN1-x layers with weak [112] texture and α-Al2O3 withstrong texture. The simulations predict that samples with weak tex-ture have higher values in elastic energy density.

4:40 PMAdhesion and Friction Behavior of Commercial Lubricants forAl5083/P20 Steel Sliding Surfaces at High TemperatureA. Morales*, V. Franetovic, General Motors R&D Center, USA

Quick Plastic Forming (QPF) of aluminum sheet requires high tribo-logical performance of the lubricant at the aluminum/steel sliding in-terfaces due to the reactivity between aluminum and steel at the highforming temperature (450°C). Improvement of the tribological con-ditions for the process can be achieved by tailoring the lubricant toavoid adherence of aluminum to the forming tool. Extensive workhas been carried out at GM R&D to find a lubricant with better tribo-logical performance than the one used in production. Several lubrica-tion companies have submitted samples for analysis under QPF con-ditions. Adherence of these lubricants to the aluminum sheet andtheir tribological performance under QPF conditions were evaluatedand compared with the current production lubricant. Some of the lu-bricants studied partially conformed to the requirements specifiedfor the as-received QPF materials and need to be modified to achievebetter performance.

5:00 PMInfluence of thermal exposure on the interfacial microstructure ofStellite 6 coated 12%-Cr steels for steam turbine applicationsC. Leinenbach*, A. Al-Badri, M. Roth, EMPA - Materials Science &Technology, Switzerland

9-12% Cr steels are widely used in turbine parts in steam powerplants because of their good mechanical properties and corrosion re-sistance at elevated temperatures. However, parts like valve seats andspindles are prone to oxidation, particle erosion or wear. This re-quires the application of protective coatings with adequate mechani-cal properties, wear and spalling resistance. Cobalt based coatingslike Stellite 6 are applied for service temperatures up to 550°C, butsteam temperatures of up to 700°C are planned for future powerplants in order to decrease the CO2 exhaustion. In this work, the in-terfacial microstructure of Stellite 6 coated 12% Cr steel before andafter long term annealing at elevated temperatures (up to 650°C and10’000 h) was characterized. The experimental results were com-pared with the results of additional thermodynamic simulations. Itcould be shown that a thin (~20 μm) hard and brittle interlayerforms during annealing.

5:20 PMWear behavior of nanocrystalline nickel-tungsten alloy coatingsJ. A. Hamann*, Xtalic Corporation, USA; C. A. Schuh, Massachusetts Instituteof Technology, USA; A. C. Lund, Xtalic Corporation, USA

Electrodeposited nanocrystalline Ni-W alloy coatings have been sug-gested as a replacement for traditional hard chromium due to the

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 221

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania222

lower environmental impact of processing. However, any such substi-tution would require equivalent performance in service, includingunder wear conditions. A particularly interesting feature of nanocrys-talline Ni-W is that unexpected and unique mechanical responseshave been identified at particular nanoscale grain sizes. Furthermore,it has been shown that such novel mechanical properties have can beinvoked by changing processing parameters. The present study con-siders the wear behavior of such hard metal coatings measured bypin-on-disk tests under varying loading conditions. By comparingnanocrystalline Ni-W and hard chrome, we identify unique deforma-tion mechanisms for the two materials. The results presented hereoffer new interpretations regarding the relationships between nanos-tructure, hardness, and wear behavior in electrodeposited coatings.

Materials & Systems: InternationalSymposium on Innovative Processing andSynthesis of Ceramics, Glasses andComposites

Polymeric and Chemical ProcessingRoom: 336Session Chair: Davion Hill, DNV Research and Innovation - CCTechnolgies

2:00 PMDevelopment of Monolithic and Dense Polymer Derived SiOCfrom Commercial PolymethylsilsesquioxaneM. Esfehanian*, R. Oberacker, M. J. Hoffmann, University of Karlsruhe,Germany; T. Fett, Karlsruhe Research Center, Germany

Development of monolithic and dense polymer derived ceramics inthe Si-O-C system was studied without using of any filler particles orcatalysators. For this purpose a commercial polymethylsilsesquioxanepowder was first pyrolyzed at 900 °C and then hot pressed at the tem-perature range of 1400-1600 °C. Dense SiOC discs with 2 mm thick-ness and 20 mm diameter were produced and characterized. β-SiCwas found in all the SiOC samples after hot-pressing. Excess carbonwas detected above 1500 °C in form of turbostratic graphite. Flexuralstrength (219 MPa) and the Young’s modulus (89 GPa)of the sampleswere measured by ball-on-three-balls method and ultrasonic time offlight device; repectively.

2:20 PMElectrical Behavior of Polymer-Derived Amorphous CeramicsL. An, T. Jiang*, University of Central Florida, USA

Polymer-derived ceramics (PDCs), which are synthesized by thermaldecomposition of polymeric precursors, exhibited unique propertiesand structures. In this paper, we report on the studies of the electricalbehavior of polymer-derived ceramics. Temperature-dependent con-ductivity of the PDCs synthesized at different temperature is meas-ured; and the results show that the conductivity follows typical amor-phous semiconducting behavior. The temperature-conductivityresults are used to estimate the variation of electronic structures ofthe materials as a function of synthesized temperatures. The resultswill be discussed in terms of structures.

2:40 PMComparison of Bulk Properties of Polymer Precursor DerivedSilicon Carbide with Sintered Silicon CarbideA. Rahman*, S. C. Zunjarrao, R. P. Singh, Oklahoma State University, USA

Polymer precursor derived silicon carbide ceramics made by polymerinfiltration and pyrolysis (PIP) technique offer various advantagesover conventional processing, such as near net shape fabrication, rel-atively low temperature processing and the ability to tailor the mi-crostructure. In this work, a comparison has been conducted betweenproperties of polymer precursor derived silicon carbide and commer-

cially available sintered silicon carbide. Silicon carbide samples arefabricated by pyrolysis of allylhydridopolycarbosilane at differenttemperatures. Average grain size is determined using XRD. Nanoscalemechanical properties in terms of modulus and hardness and bulkscale characterization in terms of flexure strength have been meas-ured. Nanoscale as well as bulk properties of commercially availablesilicon carbide were higher than PIP derived SiC, however, for the lat-ter some improvement in properties is observed with increasing pro-cessing temperature.

3:40 PMProcessing of Uranium Carbide based Silicon Carbide MatrixComposites Using Polymer Infiltration and PyrolysisA. K. Singh*, A. Apblett, R. P. Singh, Oklahoma State University, USA

Uranium carbide (UC) reinforced SiC matrix composites were pre-pared using polymer infiltration and pyrolysis (PIP). The polymer in-filtration and pyrolysis based technique involves lower energy re-quirements than conventional sintering processes currently inpractice. The starting materials were powders of UC or UH3, and al-lylhydridopolycarbosilane (AHPCS), which is an organometal poly-mer precursor for silicon carbide. Inert gas pyrolysis of AHPCS pro-duces near-stoichiometric amorphous silicon carbide (a-SiC) at900–1150C. X-ray diffraction study indicated that uranium hydride,during its pyrolysis with AHPCS, was converted to uranium carbide.Furthermore, microstructural analysis showed a uniform distribu-tion of the filler particles in the silicon carbide matrix. Pellets havinginclusions were observed to show ductile failure during biaxial flex-ure testing with increased load capabilities in comparison to neat sili-con carbide based composites.

4:00 PMPressure Filtration Processing and Testing of Ceramic SlipsE. Medvedovski*, C. J. Szepesi, Umicore Indium Products, USA

The study of properties of ceramic slips is necessary for prediction ofceramic bodies processing and their drying and sintering behavior.Pressure filtration (baroid filtration) testing can be successfully usedfor evaluation of ceramic slips combining it with traditionally usingdetermination of viscosity, specific gravity and pH. This testing in-cludes the study of the filter-cake formation under pressure usingmembranes with selected fine mesh sizes. This technique may be alsoemployed for manufacturing of dense and porous ceramic bodies. Asan example, results of the pressure filtration studies conducted fordifferent aqueous indium-tin oxide ceramic slips prepared by ballmilling and attrition milling are reported. This technique assists toevaluate and explain the features of stating powders, dispersability ofthe slips, shaping behavior, green ceramic body compaction, sinter-ability, and it also assists in conducting of fast actions to improve ce-ramic processing.

4:20 PMProcess Design and Production of Boron Trichloride from NativeBoron Carbide in Lab-ScaleD. Agaogullari*, I. Duman, Istanbul Technical University, Turkey

The aim of this study is the production of boron trichloride (as one ofthe gaseous starting materials of boron fiber manufacturing by hotfilament CVD) from native boron carbide.For the production processtwo different originally designed systems are used.The reaction oc-curs by passing chlorine through boron carbide(3-3000μm) layerswith different heap heights(2-10cm).The reactor is a perpendicularquartz tube heated to 450-1000°C by a tube furnace.Flow rates ofchlorine(100-1000 ml/min),pressure and temperature changes in thesystem are controlled by MFC,mercury manometer,thermocoupleand thermometers.The produced gases are separated in distillationcolumns;waste gases are sent to gas scrubber.Gases,liquids and solidsare analyzed with FTIR,AAS,XRD,SEM/EDS and EPMA.The conver-sion efficiencies of chlorine are assigned.In pipelines,traps and con-

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 222

Wed

nes

day

PM

www.matscitech.org 223

densers various metal (i.e. Fe,Al,W,Si,Cr ) halides depending on theimpurities of boron carbide are detected in gas,liquid and solid forms.

4:40 PMSynthesis and Photocatalytic Properties of Mesoporous TitaniumDioxideI. Kolesnik*, M. Kharlamova, A. Eliseev, A. Lukashin, Y. D. Tretyakov, MoscowState University, Russian Federation

The aim of present study was the synthesis of mesoporous titaniumdioxide via template approach and revelation of correlations betweensynthesis parameters, phase composition, surface area and photocat-alytic activity. It was found out, that in case of using cationic as a sur-factant pH and ultrasonic treatment are the most crucial parameterswhich determine the morphology of mesoporous titania. Comparingto mesoporous samples obtained in alkaline media, products synthe-sized at neutral pH have thick pore walls and good thermal stability.Ultrasound has the similar effect. Using of non-ionic surfactant as atemplate allows to obtain mesoporous TiO2 with high specific surfacearea (320 m2/g) and nanocrystalline pore walls. The most photocat-alytically active samples consist of two phases – anatase and brookiteand contain minimal amount of amorphous phase. This work wassupported by RFBR (grants 06-03-89507, 06-08-01443) and FASI(grant 02.523.12.3015)

Nanotechnology: Controlled Processing ofNanoparticle Structures and Composites

Novel Nanoparticle ProcessingRoom: 408Session Chair: Kathy Lu, Virginia Polytechnic Institute and StateUniversity

2:00 PMMicrostructural control of Si3N4 and AlN ceramics usingnanocomposite particles prepared by mechanical treatment(Invited)J. Tatami*, Yokohama National University, Japan; H. Nakano, RyukokuUniversity, Japan; T. Wakihara, K. Komeya, Yokohama National University, Japan

In this study, nanocomposite particles prepared by mechanical treat-ment were used to control microstructure of Si3N4 and AlN ceramics.In Si3N4 ceramics, it was observed that TiO2 nanoparticles and Si3N4particles were directly bonded in spite of the treatment at room tem-perature. As a result, TiN nanoparticles were well dispersed in Si3N4matrix compared with conventional wet mixing to improve bendingstrength and wear behavior. In AlN ceramics, Y2O3 nanoparticles werealso directly bonded onto AlN particles and Al2O3 layer on the AlNparticle were reacted with Y2O3 to form crystalline and amorphousyttrium aluminate. AlN ceramics fabricated using the nanocompositeparticles had more uniform microstructure with smaller grain. Con-sequently, it was found that the use of nanocomposite particles pre-pared by mechanical treatment was effective in the microstructuralcontrol of Si3N4 and AlN ceramics.

2:40 PMMild Dispersion of NanoparticlesH. Way*, NETZSCH Fine Particle Technology, USA

Many dispersion processes can break down the nanoparticles’ pri-mary particles, ruining the surface conditions, crystal structure andoverall chemistry, rendering them ineffective. But, NETZSCH’s millsutilize mild dispersion, a new trend, which is a condition of a beadmill that eliminates contamination and breakage of particle charac-teristics by dispersing with multiple mild contacts (micro beads) in-stead of one strong contact. Bead mills now employ beads as fine as30-50 micron. It is possible to maintain the chemical integrity andstructure of sub-micron particles, even through the grinding and dis-persion processes. Harry Way, NETZSCH’s technical director, will in-

troduce mild dispersion technology used to eliminate the breakageand contamination of nanoparticles during dispersion. Thorough ex-planations and applications of mild dispersion, as well as other fac-tors affecting the mild dispersion process (bead size, disc options, andspeeds) will be covered.

3:40 PMEngineered Nanostructures For Multifunctional Single-WalledCarbon Nanotube Reinforced Non-Oxide CeramicNanocomposites (Invited)E. L. Corral*, Sandia National Laboratories, USA

Colloidal processing was used to make highly dispersed aqueousnanocomposite suspensions containing single-wall carbon nan-otubes (SWNTs) and Si3N4 particles. The SWNTs and Si3N4 particleswere stabilized into nanocomposite suspensions using a cationic sur-factant at low pH values. Bulk nanocomposites containing 1.0, 2.0,and 6.0 vol% SWNTs were successfully fabricated using rapid proto-typing. The SWNTs remain pristine in the nanostructure after hightemperature sintering (1800 °C). The engineered nanostructureshave an increase in grindability and a higher damage tolerance behav-ior over the monolith. Toughening mechanisms such as, SWNT crackbridging, and fiber pull-out indicate that SWNTs have the potentialto serve as toughening agents in brittle ceramics. This study reportsthe effects of colloidal processing on mechanical behavior of SWNTreinforced non-oxide ceramic nanocomposites.

4:20 PMMicrostructure, Precipitation and Deformation Behavior of NovelSpinodal FeNiMnAl AlloysI. Baker*, J. A. Loudis, J. Hanna, X. Wu, Dartmouth College, USA

Several FeNiMnAl spinodal alloys, which consist of a periodic two-phase microstructure of 10-60 nm wide interconnected rods withfully coherent {100} interfaces, have been studied. The (Ni,Al)-richB2 and (Fe,Mn)-rich b.c.c. phases differ in lattice parameter by<0.5%. As-cast hardness values and compressive yield strengths are∼500 VPN and ∼1500 MPa, respectively. A low volume fraction ofspherical prolate 75 nm (Fe,Mn)-rich precipitates with the α-Mnstructure are present in the alloys, while (Fe,Mn)-rich precipitateswith the β-Mn structure form upon annealing at 550°C. Both sets ofprecipitates have well-defined relationships with the matrix. Thelenticular β-Mn grows to ∼1μm and 200-300 nm wide after 100h an-neals resulting in increases in hardness and yield strength to ∼770VPN and ∼2300 MPa, respectively. Deformation was found to be bythe glide of paired 1⁄ 2 <111> dislocations. Research supported byDOE grant DE-FG02-07ER46392 and the NSF Graduate ResearchFellowship Program.

4:40 PMProduction of innovative ceramic nano powders via PulsationReactor ProcessL. Leidolph*, IBU-tec advanced materials GmbH, Germany

IBU-tec’s pulsation reactor technology is an innovative novel thermalprocess. This thermal reactor, a proprietary development of IBU-tec,is the reactor of choice for material transformation processes in thechemical industry and for the production of nano-sized powders.The raw materials injected into the reactor receive thermal shocktreatment with extremely short retention times. This creates a newgeneration of nano-particles which feature a highly reactive surfaceor of fine-grain materials such as nano-sized powders. Moreover,variations in temperature and retention times allow to specify fea-tures of the powders. Physico-chemical characteristics of some of thefabricated powders will be investigated and tabulated. The resultsshow the possibilities of the production of nano metal oxide powdersas well as multi oxide powders on industrial large scale applying pul-sation reactor. Composite or core shell materials combine differentproperties, e.g. UV-protection and scratch resistance.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 223

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania224

5:00 PMSynthesis of Nanostructured LaB6 Powders for Micro- and Nano-satellite Propulsion ApplicationsO. A. Graeve*, R. Kanakala, G. Rojas-George, University of Nevada, Reno, USA

The goal of this project was to demonstrate the feasibility ofpreparing nanocrystalline LaB6 powders via a controlled combus-tion synthesis process. These powders are extraordinarily strongelectron emitters with applications in micro- and nano-satellitepropulsions systems, where they can serve as substitutes for chem-ical propellants. During this process, controlled amounts of lan-thanum nitrate (oxidizer) and amorphous boron were reactedwith carbohydrazide (fuel) in a muffle furnace. As the reactantswere heated, the oxidizer and fuel reacted to form a fine violetpowder that contains both nanocrystalline LaB6 and unreactedboron. After synthesis, the unreacted boron was removed from thepowders using a controlled acid wash. The resulting phase-pureLaB6 powders were then characterized using x-ray diffraction forphase purity and crystallite size, scanning electron microscopy forparticle morphology, and dynamic light scattering for particle sizedistribution.

5:20 PMTitanium Nanoparticles Production by Using Vapors of Sodiumand Titanium TetrachlorideA. Attar, M. Halali, A. Sangghaleh*, Sharif University of Technology, Iran

In this paper, titanium nanoparticles have been produced using theNa/TiCl4 reaction in the gas phase. The size of the synthesized tita-nium particles are in the range of 20 to 100 nm. Nucleation andgrowth of Titanium nanoparticles are investigated. The effect oftemperature on the size of the particles is also studied. Scanningand transmission electron microscopic studies have been per-formed to evaluate the characteristics of produced particles. Theoptimum temperature is set to be 650°C in which the finest parti-cles are observed.

Nanotechnology: Nanotechnology for PowerGeneration

Nanotechnology for Power Generation IRoom: 409Session Chairs: Navin Manjooran, Siemens AG, Energy; GaryPickrell, Virginia Polytechnic Institute and State University

2:00 PMSynthesis of Nano-metric Oxide Dispersion Strengthened (ODS)Ferritic Stainless Steels from Gas Atomized Precursor Powders(Invited)I. E. Anderson*, Ames Laboratory, USA; J. R. Rieken, Iowa State University,USA; M. J. Kramer, D. Shechtman, M. F. Besser, Ames Laboratory, USA

As an alternative to mechanical alloying, Fe-Cr based powders, en-capsulated with a thin precursor oxide shell, were produced by gas at-omization reaction synthesis (GARS). Hot isostatic pressing (HIP)fully consolidated the powder and heat treatment promoted diffusionand exchange reactions that dissolved the trapped oxide shells andgenerated stable oxide nano-dispersoids in the microstructure. Re-sults will be reported of the transformations that convert the Fe-(12.5-15.0)Cr-(0.3-1.0)Y (wt.%) powders to an isotropic ODS mi-crostructure, including the effects of reduced oxygen and Ti and Wadditions on development of an ideal (fully transformed) mi-crostructure. Heat-treated microstructures were analyzed by SEMand TEM. Changes in product phases were tracked with x-ray diffrac-tion. High temperature tensile strength measurements assessed theeffectiveness of the heat treatments. Supported by DOE-FE-ARMthrough Ames Lab contract no. DE-AC02-07CH11358.

2:40 PMStructural changes and stability of pore morphologies of a porousglass at elevated temperaturesB. L. Scott*, G. Pickrell, Virginia Polytechnic Institute and State University, USA

A spinodally phase separable porous glass was evaluated for poremorphology changes after undergoing heat treatments from 600 C to900 C. Glass samples with varying starting pore structures weretreated at elevated temperatures for times ranging from 5 minutes upto 24 hours. The glass was characterized through the use of a nitrogenadsorption technique to determine the pore size distribution, surfacearea and pore volumes as a function of treatment conditions. Resultsshow that some of the glasses have an average pore size that does notchange with treatment conditions while other glasses show an evolu-tion in the average pore size and pore morphology. The pore mor-phology of this can be controlled with heat treatments to the porousglass and under certain conditions show pore stability at elevatedtemperatures.

3:40 PMResistivity measurement of nano/microwiresS. Annamalai*, I. L. Pegg, B. Dutta, The Catholic University of America, USA

Resistivity measurements of PbTe nano/microwires are presented as afunction of temperature and wire diameter. Resistivity measured bytwo-probe and four-probe configurations has been compared to de-termine the effect of contact resistance arising from silver elec-trode/nano/microwire interface. The nano/microwires were co-drawn in a conventional optical fiber drawtower with a glass-claddingsuch that the diameter of the wires varied between 100 to < 1 μm.Such glass-clad fibers were either etched at both ends to perform two-probe measurements or the glass claddings were totally removed toperform four-probe measurements to avoid contact problems. BulkPbTe exhibits metal-insulator transition (MIT) around 500K. PbTewires of certain sizes also exhibit another MI transition around 725K.Wires of diameter 3 μm or less do not exhibit this MI transition at500K, but they exhibit a change in slope of ln ρ vs 1/T curve aroundthis temperature. A detailed experimental procedure for resistivitymeasurement of nano/microwires is presented.

4:00 PMConstruction of Electronic Device Components on Nano-PorousGlass Fibers Using Electroless Deposition, Chemical VaporDeposition, and Dip Coating TechniquesM. Wooddell*, G. Pickrell, Virginia Tech, USA

A novel fiber optic sensor has been developed that contains a three di-mensionally interconnected pore structure surrounding a solid core.The objective of this work is to increase the functionality of these op-tical fiber sensors by integrating electronic device components on thefiber surface and in the fiber pore structure. Conductive copper path-ways were created on/in the fibers using electroless deposition and athin film of silicon was deposited via chemical vapor deposition usinga mixture of SiCl4 and H2. Additionally, conductive poly(3,4-ethyl-enedioxythiophene)-poly(styrene sulfonate) photoactive polymerblend poly(3-hexylthiophene) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-)6,6)C61 were deposited using dip coating techniques. Opti-cal microscopy, SEM, and EDS analysis show that the copper, silicon,and electrically active polymers were deposited in the pore structureand/or on the surface of the fiber.

4:20 PMPreparation and Lubricating Performance of Oil-based NanofluidsContaining Carbon NanoparticlesC. Choi, J. Oh*, M. Jung, K. Ahn, Korea Electric Power Research Institute,South Korea

In this presentation, several lubricant-based nanofluids were pre-pared adding fullerene(C60), graphite and carbon black nanoparti-cles with an average diameter of 20-50nm. The tribological and ther-

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 224

Wed

nes

day

PM

www.matscitech.org 225

mal behaviors of nanofluids were investigated with a tribo-tester anddynamic thermal tester. It is obvious that the combination ofnanoparticle, surfactant and surface modification processes is veryimportant to optimize the dispersion of nanofluids. We also foundthat an ‘optimal particle size’ existed for tribological applications. Thenanofluids with 0.5% vol. fractions of graphite and carbon blackshowed a decrease of over 30% in friction coefficient and oil temper-ature compared to pure lubricating oil. The nanofluids that containedcarbon black showed excellent dispersion, tribological and thermalproperties, similar to those of the graphite nanofluids. Therefore, thenanofluids that contain carbon black are considered to be the mosteconomical and high-efficient lubricant.

4:40 PMSynthesis of Nanostructured Metallic Glasses by Ion IrradiationJ. Carter, M. Martin, L. Shao*, Texas A&M University, USA

The lack of crystal defects in metallic glasses gives them uniquechemical and mechanical properties such as high strength and highcorrosion resistance. However, the application of metallic glasses asstructural materials has been limited by their poor ductility. Onestrategy to improve ductility is to introduce nanocrystals into anamorphous matrix. In this talk, we report our recent progress informing nanocrystal-embedded metallic glass using ion bombard-ment. The study shows the feasibility of the technique to develop highstrength alloys. Furthermore, we obtained clear evidence thatnanocrystals are formed due to thermal spike and damage cascadeformation during ion-solid interaction. Phase changes, element seg-regation, mechanical property changes will be discussed for He andCu ion irradiated Cu50Zr45Ti5 glass. Results from atomic force mi-croscopy, scanning electron microscopy, transmission electron mi-croscopy, indentation tests and 3 dimensional atom probe tomogra-phy will be presented.

5:00 PMNanomaterials for Energy Applications: Storage, Efficiency,Conversion and GenerationR. L. Vander Wal*, USRA c/o NASA-Glenn, USA

Though the synthesis of a host of organic and inorganic nanomateri-als has been demonstrated their integration into practical applica-tions remains highly challenging. With energy at the forefront of thenational economy and security, particular emphasis is given to en-ergy-directed applications. Not surprisingly, energy and materials areintimately related. Many forms of energy utilization, conversion andstorage and generation are dominated by interfacial reactions.Therein nanomaterials as an interfacial modifier will play a criticalrole in these processes. Specific space and aerospace application top-ics will include: 1) Tribilogy - nanolubricants 2) Energy Storage - Liion batteries 3) Polymeric Composites - interfacial modifiers 4) Sen-sors - metal oxide semi conductors 5) Aerodynamics - pressure sensi-tive paint supports 6) Catalysis - nanostructured oxides Highlights ineach application will be presented.

Processing & Product Manufacturing: Joiningof Advanced and Specialty Materials X

Welding Metallurgy and Welding in Nuclear IndustryRoom: 410Session Chairs: Viola Acoff, University of Alabama; BoianAlexandrov, The Ohio State University

2:00 PMLaser Welding of Zn-coated Advanced High Strength Steels(Invited)Y. Zhou*, University of Waterloo, Canada

This presentation will provide an overview of the research activitieson laser welding of advanced high strength steels at the University of

Waterloo. This research is part of the effort to improve vehicle fuel ef-ficiency by reducing the body weight. This talk will focus on the weld-ability of various Zn-coated DP and TRIP steels and also the forma-bility of welded joints.

2:40 PMReconstitution Charpy Test Specimens by Electron Beam WeldingP. I. Petrov*, Institute of Electronics, Bulgaria

The reconstitution is a powerful technique that allows re-using bro-ken Charpy test specimens. It allows performing additional Charpyor fracture toughness tests on limited amount of available materialand can contribute to a better characterization of the material andtherefore to a better evaluate the degree of embrittlement of the reac-tor pressure vessel steel due to neutron irradiation. This paper reportsresult from reconstitution of the Cv-type specimens form 18MND5low alloyed steel by electron beam welding (EBW). The experimentswere carried out using 15 kW Leybold Heraeus welding unit. Weld-ability of pressure vessel steel by EBW was investigated in accordanceEN ISO 13919-1 standard. There were made investigations of struc-tural changes of metal in welds and heat affected zones to determineinfluence of welding thermal cycle. Static three point bend tests onun-notched specimens show good resistance of the weld. Charpy im-pact tests show good agreement between original and reconstitutedspecimens.

3:40 PMFlux System Optimization for Shield-Metal Arc WeldingElectrodes for High Nickel AlloysK. Sham*, S. Liu, Colorado School of Mines, USA; G. Young, LockheedMartin Corporation, USA

The goals of this work are to develop a shielded metal arc (SMA)welding electrode with optimal weldability and corrosion resistancewhile diminishing the ductility-dip and solidification cracking andshow the viability of a unified filler metal composition for both barewire and flux coated welding processes. Experimental nickel alloyrods (20Cr, 24Cr, 27Cr, and 30Cr wt%) were used for the extrusion ofelectrodes. A base flux coating was successfully designed that demon-strated comparable weldability relative to commercial products, withincreased puddle fluidity and acceptable slag detachability. Withminor alloying additions, flux coatings consisted of CaCO3, TiO2,and Na3AlF6 are commercially viable for SMA welding. The optimalalloy displayed the best combination of weldability, corrosion resist-ance, and cracking control. Results to-date point in a positive direc-tion in achieving an improved high nickel alloy SMA electrode.

4:00 PMIrradiation Effects in W, Ta, and Steel Diffusion BondsA. T. Nelson*, University of Wisconsin, USA; D. E. Dombrowski, S. A. Maloy,Los Alamos National Laboratory, USA

In support of ongoing efforts to develop joining techniques suitablefor elevated-temperature nuclear environments, diffusion bonding isbeing investigated as a means of joining tungsten and tantalum to fer-ritic/martensitic stainless steels. A test matrix of bonding conditionswith temperatures ranging from 800 to 1200 C (1500–2200 F), pres-sures extending from 3 to 50 MPa (.5–7 ksi), and times varying from1 to 24 hours has been implemented to determine the conditions suf-ficient to achieve the required mechanical and thermal bond per-formance. Furthermore, an array of coatings has been investigated toserve as a bonding interlayer to improve adhesion and reduce residualbonding stresses. The most promising interfaces will be irradiatedusing 2.5 MeV protons to 2 dpa at temperatures ranging from 200 to300 C (390–570 F). Following irradiation, the resulting evolution ininterface morphology will provide insight into the potential effect ofprolonged exposure to neutron and proton fluences on diffusionbond performance.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 225

Wed

nesd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania226

4:20 PMMicrostructure Control in Welded Joints of HSLA SteelsB. T. Alexandrov*, J. C. Lippold, E. Gould, Ohio State University, USA

The modern thermo-mechanical processes in steel production havesignificantly improved the mechanical properties of weldable struc-tural steels. In order to match these properties, the welding consum-ables for HSLA steels are alloyed with higher amounts of nickel, man-ganese, and molybdenum. This results in different weld metal andHAZ phase transformation behavior and limits the operational win-dow of heat inputs that produce optimal joint properties. The tech-nique for Single Sensor Differential Thermal Analysis was applied todevelop in-situ HAZ and weld metal continuous cooling transforma-tion (CCT) diagrams for GMA welds in steel HSLA100 with ER100S-G welding consumable. These diagrams were superimposed to deter-mine the range of cooling rates that yield optimal combinations ofweld and HAZ microstructures and properties. It has been shownthat development of CCT diagram data base for HSLA steels andwelding consumables could significantly facilitate the process of con-sumable selection and welding procedure development.

4:40 PMFabrication of Monolithic U-Mo Fuels by Hot Isostatic PressingB. H. Park, J. Jue*, G. A. Moore, C. R. Clark, D. K. Keiser, Idaho NationalLaboratory, USA

The goal of the RERTR program is to develop advanced nuclear fuelsfor the research and test reactors with the enrichment of uraniumbelow twenty percent. Currently, a dispersion fuel type has been qual-ified and used in many research and test reactors. For the high powerreactors such as ATR and HFIR, the uranium density in the currentqualified dispersion fuel type is not sufficient. Monolithic fuel type isunder development because this fuel type can provide high enoughuranium density to meet the requirements of high power reactors.The main technical challenge for the fabrication of monolithic fueltype is to bond the monolithic fuel meat to the cladding. One of themethods to bond the aluminum alloy cladding to monolithic fuelmeat is by hot isostatic pressing. This paper summarized the currentstatus of this development effort at the Idaho National Laboratory.

Processing & Product Manufacturing:Processing, Properties and Performance ofComposite Materials

Metal Matrix Composites - ProcessingRoom: 412Session Chairs: Ajit Roy, Air Force Research Laboratory; JohnLewandowski, Case Western Reserve University

2:00 PMProcessing of In-Situ Aluminum Metal-Matrix CompositesD. Spears, S. Viswanathan*, R. G. Reddy, The University of Alabama, USA

Liquid state processing is the preferred route for the production ofparticulate reinforced Metal Matrix Composites (MMCs) due to thelower cost and the ability to form a variety of shapes. However, thedisadvantages of liquid state processing include the cost of the rein-forcement, reaction between the particulate and liquid alloy, and theentrapment of gas or air bubbles during stirring of the reinforcementinto the liquid alloy. In this work, a reactive gas is bubbled through analuminum alloy melt. The reinforcing particles nucleate and grow di-rectly from in-situ chemical reactions between molten metal and a gassource. Since the particles are formed in situ, they are thermodynam-ically stable and free of surface contamination, thereby yielding betterinterfacial properties that will not degrade during service. The processfor the production of in-situ composites is detailed, and the mi-crostructure and properties of the resulting MMC are characterized.

2:20 PMReinforcement of aluminum by AlB2 flakes at high volumefractions and alignmentJ. Meyer*, J. Economy, University of Illinois at Urbana-Champaign, USA

High aspect ratio aluminum diboride (AlB2) single crystal flakes havebeen shown to provide high reinforcement to an aluminum matrixwith strength and modulus values increasing with volume fractionand degree of flake alignment. High aspect ratio flakes were preparedfrom a commercial material, consisting of low aspect ratio AlB2 in Al,by heating near the peritectic temperature of 956oC. The flake volumefraction was increased by filtration at 675oC and alignment increasedby melt shear and hot pressing. At 30v/o a 95% increase in moduluswas observed over the matrix material to 125GPa, with similar in-creases in the flexural and tensile strength. Melt shear and hot press-ing have been observed to improve the alignment from 0.21 at 30v/oto over 0.55. With these enhancements to the alignment, a modulusof 149GPa and flexural strength of 273 MPa was achieved. These re-sults demonstrate that highly aligned AlB2 flakes provide excellentimprovements to the strength and modulus of an aluminum matrix

2:40 PMManufacture and Mechanical Properties of Metal MatrixSyntactic FoamsY. Zhao*, X. Tao, X. Xue, The University of Liverpool, United Kingdom

Metal matrix syntactic foams are a class of composite materials con-sisting of a continuous metal matrix embedded with hollow orporous ceramic particles. In comparison with metal foams, they havehigher compressive yield strength and more homogenous mechanicalproperties, although they usually have higher densities. Because ofthe existence of porosity, they also have the ability to absorb impactenergy. They have the potential to serve as lightweight structures asenergy absorbers against impact or as replacement bone implants.The paper introduces Al and Ti syntactic foams fabricated by pressuremelt infiltration and powder metallurgy, respectively. Their behav-iour in compression and indentation is studied. The distinctive ef-fects of the porous and hollow ceramic microspheres on the mechan-ical properties and the deformation mechanisms are discussed.

3:40 PMDevelopment of Cold Spray Composite Coatings Non DestructiveCharacterizationM. A. Lubrick*, R. Maev, V. Leshchynsky, University of Windsor , Canada

High porosity within a coating can have detrimental effects on manyproperties including adhesion and corrosion protection. Also one cannot always rely on sample data as a fair estimate for sprayed proper-ties especially in a process as variable as cold spray. Thus low cost,simple nondestructive methods to determine porosity for any combi-nation of coatings and substrate are quite valuable. In this study thelow pressure gas dynamic spray process was used to apply 3 differentcomposite coatings. The samples were than studied using regularacoustic methods and sound velocity was determined at 4 points oneach sample to determine an average. Next using a YDK01 (Sartorius)density determination kit and the Archimedean principle the densitywas determined to within an accuracy of 0.1%. Using the comparedporosity and sound velocity measurements it is our hope to create adatabase by which future coatings can be compared and porosity esti-mated nondestructively.

4:00 PMNanocrystalline W Reinforced Amorphous Ni-W MatrixCompositesA. Zeagler*, A. O. Aning, Virginia Tech, USA

Starting with the equiatomic composition of Ni and W elementalpowders, mechanical alloying (by SPEX mill) was used to producepowders of Ni-rich amorphous phase containing uniform dispersionof nanocystalline W. The powders were compacted using a combus-

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 226

Th

urs

day

AM

www.matscitech.org 227

tion driven compaction device that utilizes controlled release of en-ergy from combustion of natural gas. The resulting compacts werecharacterized microstructurally (optical, SEM, EBSD), and mechani-cally (hardness). Findings will be presented and discussed.

4:20 PMEffect of Pressure and Plastic Deformation on Alumium -BerylCompositesD. H. Basavaraj, S. K. Rama Reddy*, M. p. Jebaraj, C. M. Puttaiah, S E ACollege of Engineering & Technologyg, India

‘Beryl’- a naturally has density close to that of Aluminium and posseshigh hardness (7.5 – 8 on Mho’s scale). The tensile strength increasestill 6 % addition of beryl particles to aluminium matrix, and so alsothe hardness. Further the composites were subjected to followingprocessing conditions: i) Gravity castings(G) with out any pressure orplastic deformation ii) Casting with pressure during solidification(Squeeze casting(S) iii) Gravity cast and plastically deformed (G + F),iv) Casting with pressure during solidification and later plastically de-formed (S+F) The results are: a) Tensile strength increases in the fol-lowing manner : S (+ 12%); GF (+ 29.18%); S F (248.5 MPa) ( +34.21%) as compared to gravity cast composites (G) ( 185 MPa)b)Hardness has also same order S,GF, SF(+35.5%) against G ( 60)c)SF composites,showed wear rate of 41% lower, followed by GF (34.5%) and S (31.8%) when compare to gravity cast composites(G).

4:40 PMA Route for Obtaining NiCrAl-Al2O3 Composite PowdersE. T. Kubaski*, D. G. Simoes, University of Sao Paulo - Escola Politecnica,Brazil; O. M. Cintho, Universidade Estadual de Ponta Grossa, Brazil; J. T.Capocchi, University of Sao Paulo - Escola Politecnica, Brazil

The aim of this work is to produce NiCrAl-Al2O3 composite powdersusing high-energy milling and NiO, Cr and Al powders as startingmaterials. Four compositions were prepared: (1) 3NiO:3Cr:5.5Al; (2)3NiO:0.903Cr:2.679Al; (3) Ni:0.301:0.145 and (4) 3NiO:2.2Al. Thetwo first compositions were processed to obtain NiCrAl-Al2O3 pow-ders, while the others were used to characterize the reaction that takesplace during milling. All compositions were milled in a Spex 8000Mmixer/mill. The millings were conducted for several times, underargon atmosphere, and a ball-to-powder ratio of 7:1 were used. Theas-milled powders were characterized using X-ray diffraction (DRX),scanning electron microscopy (SEM) and differential thermal analy-sis (DTA). DRX and SEM results showed the formation of Ni3Al andAl2O3 after the composition (2) have been milled for 2hours. Com-positions (3) and (4) and DTA analysis were used to evidence that re-actions which took place during milling were related to the alu-minothermic reduction of NiO.

5:00 PMUsing Microwave Assisted Powder Metallurgy Route and Nano-size Reinforcements to Develop High Strength Lead-free SolderCompositesM. Nai*, M. Alam, X. Zhong, P. Babaghorbani, National University ofSingapore, Singapore; J. Kuma, Minerals, Metals and Materials TechnologyCentre , Singapore; M. Gupta, National University of Singapore, Singapore

In the present study, Sn-0.7Cu and Sn-3.5Ag lead-free solders used inthe electronics packaging industry were reinforced with different vol-ume percentages of nano-size alumina and tin oxide particulates, re-spectively, to synthesize two new sets of nanocomposites. These com-posites were developed using microwave assisted powder metallurgyroute followed by extrusion. The effects of addition of particulates onthe physical, microstructure and mechanical properties of nanocom-posites were investigated. Mechanical properties (microhardness,0.2% YS and UTS) for both composite systems increase with the pres-ence of particulates. The best tensile strength was realized for com-posite solders reinforced with 1.5 vol.% alumina and 0.7 vol.% tinoxide particulates which far exceeds the strength of eutectic Sn-Pb

solder. The morphology of pores was observed to be one of the mostdominating factors affecting the strength of materials.

Thursday, October 9, 2008

Electronic & Magnetic Materials: Fabrication,Microstructures and Interfacial Properties ofMultifunctional Oxide Thin Films

Microstructures, Defects, and InterfacesRoom: 315Session Chair: Xiaoqing Pan, University of Michigan

8:00 AMAtomic-scale Probing of Interface Effects in Ferroelectric ThinFilms (Invited)M. Chisholm*, H. Lee, Oak Ridge National Laboratory, USA

The promise of revolutionary technologies based on complex oxidethin films require breakthrough advances in the science, integrationand scaling of these materials. New capabilities to see the cation-aniondipoles in ferroelectrics is one such breakthrough that will allowquantification of the atomic structure and the corresponding polar-ization of these materials at the atomic scale. We will present atomic-level maps of ferroelectricity in the interfaces between PbTiO3-basedferroelectrics and paraelectric substrates or metallic electrodes. Thesemeasurements are made using aberration-corrected scanning trans-mission electron microscopes which provide sub-Å electron probes.The results demonstrate the importance of the electrical boundaryconditions in determining the properties of very thin ferroelectricfilms. Research sponsored by the LDRD program of ORNL.

8:40 AMInterfacial Structures of Epitaxial Perovskite Oxide Thin Films on(001) MgO SubstrateJ. Jiang*, J. He, E. Meletis, The University of Texas at Arlington, USA; J. Liu, Z.Yuan, C. Chen, University of Texas at San Antonio, USA

This work reports the 2D in-plane interface structures of epitaxialperovskite (La,Ca)MnO3 and (Pb,Sr)TiO3 films on salt-rock typeMgO substrate studied using TEM. Both (La,Ca)MnO3 and(Pb,Sr)TiO3 films exhibit good single crystal quality and a sharp in-terface with respect to the substrate. The lattice mismatch obtainedfrom cross-section TEM is -6.4% for (La,Ca)MnO3/MgO and -6.2%for (Pb,Sr)TiO3/MgO. These values are smaller than that near the in-terface regions as determined using the plan-view TEM, -8.0% for(La,Ca)MnO3/MgO and -7.14% for (Pb,Sr)TiO3/MgO. Electron dif-fraction studies and HRTEM of the plan-view interface brought aconclusion that the (Pb,Sr)TiO3 film is well commensurate with theMgO substrate over large areas, whereas (La,Ca)MnO3 film is onlylocally commensurate with the substrate. These studies further indi-cate that plan-view TEM of the interface is able to provide criticalfilm/substrate interface information that is lacking from the cross-section TEM analysis.

9:00 AMPhotovoltaic response as a probe for ferroelectric-electrodeinterfaces (Invited)K. Yao*, Institute of Materials Research and Engineering, Singapore

Many factors of ferroelectric materials determine their photovoltaicoutput, including energy band gap structure, electric polarization, di-electric constant, space charge, and electrode interfaces. Among thesefactors, the effects of ferroelectric-electrode interfaces are particularlymore significant for the thin film samples compared to bulk samples.In this talk, photovoltaic observations will be presented for ferroelec-tric (PbLa)(ZrTi)O3 (PLZT) thin films with different electrode mate-rials, and poled along different directions, ie, poled along thickness

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 227

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania228 MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania

direction or in the plane of the surface. How the interfacial character-istics affect the polarity, magnitude, and transition of the photo-voltaic outputs will be discussed. The results clearly indicate that thephotovoltaic response observed in thin films is a useful probe to in-vestigate the ferroelectric-electrode interfaces.

9:40 AMRelaxation of Langmuir–Blodgett Ferroelectric Polymer FilmsP. Liu*, J. L. Wang, X. J. Meng, J. H. Chu, Chinese Academy of Sciences,China; P. Gemeiner, S. Geiger, B. Dkhil, Propriétés et Modélisation desSolides, France

Dielectric properties of the copolymer of vinylidene fluoride and tri-fluoroethylene P(VDF-TrFE) films grown on Ba0.5Sr0.5TiO3 /Sisubstrate by Langmuir–Blodgett technology have been investigatedover the temperature range from 200 to 390 K at various frequencies.Depending on the nature of the bottom electrode, we evidence differ-ent relaxation behaviors. The bottom electrodes, we considered as Al,Pt and LaNiO3 (LNO). In case of LNO bottom electrode, at leastthree anomalies with dielectric losses are observed whereas only oneis obtained for Pt electrode. Results with LNO show that the relax-ation around 250K can be described by the Vogel–Fulcher relationand the anomaly around 360K is related with ferroelectric-paraelec-tric phase transition. These anomalies are also confirmed by both X-ray diffraction and Raman spectroscopy. Our results demonstratethat electrical boundary conditions are crucial for the P(VDF-TrFE)physical properties.

Fabrication Issues of Oxide Thin FilmsRoom: 315Session Chairs: Li Yan, Virginia Tech; Jiechao Jiang, University ofTexas at Arlington

10:00 AMMiniaturized Metal Oxide Nanoparticle Gas Sensor Arrays builton Micro Hotplate Substrates deposited with a Drop on DemandInk Jet PrinterE. R. Beach*, M. Andio, P. Morris, The Ohio State University, USA

The work presented aims to maximize the well-known gas sensitivityenhancement provided by metal oxide nanoparticles in gas sensingdevices. It is shown in this work that the small device size of the microhotplates combined with a large array of metal oxide nanoparticlesaffords an optimized sensing system. The high spatial resolution andsmall droplet size from a drop on demand type ink-jet printer wasused to fabricate sensor arrays with minute quantities of metal oxidenanoparticles from aqueous suspensions. The gas sensing results pre-sented here show this type of system can sense various types of gasesin a complex background with some selectivity due to the array ofmaterials used and possible commercial applications of this technol-ogy are discussed.

10:20 AMNanoclay-Zirconia Multilayers: Processing Optimization andLayer-by-Layer Deposition MechanismsH. Chen*, J. Luo, Clemson University, USA; X. Wang, G. Zhang, LouisianaState University, USA

A solution-based layer-by-layer deposition technique was developedto synthesize a new class of nanostructured materials consisting of al-ternating ultrathin ZrO2 layers and exfoliated clay nanoplatelets(Chen et al., J. Nanomaterials, 2008). These films are inorganic coun-terparts to the polymer-nanoclay multilayers. Here we report furtherstudies to improve the quality of dehydrated layered structures viaoptimizing the selection of clays, exfoliation method, dipping proce-dure, and post-deposition dehydration process. These multilayers arecharacterized by SEM, XRD, AFM and nanoindentation. Further-more, controlled experiments are conducted to probe the layer-by-layer deposition mechanisms and film growth kinetics. The growth of

nanoscale hydrated zirconia films on clay surfaces is regarded as asurface mediated sol gel process, while the effects of large and nega-tive surface charges of nanoclays are expected to be significant. Possi-ble applications are discussed.

10:40 AMComparing Epitaxial Growth of MgO and CaO Films on GaNSurfacesM. D. Losego*, H. Craft, S. Mita, T. Rice, R. Collazo, Z. Sitar, J. Maria, NorthCarolina State University, USA

Integration of ferroelectric oxides with GaN is attractive for loweringMOSFET operating voltages and enhancing device functionality. Thisinvestigation focuses on molecular beam epitaxy of rocksalt oxides(MgO, CaO) on GaN as large bandgap electronic interfacial barriersfor ferroelectric oxide integration. The growth of (111) FCC crystalson a (0001) hexagonal lattice results in twinning, which is character-ized by both x-ray diffraction and electron microscopy. Differences inthe MgO and CaO growth modes (3D vs. S-K) lead to variations infilm mosaicity and structure. These structural variations cause differ-ences in electrical leakage through the film. Films of solid solutioncomposition (Mg,Ca)O lattice-matched to GaN are investigated toreduce leakage current. Understanding the dual component volatility(Mg and O2) of this ternary system is critical in controlling the mixedoxide’s composition and improving the film’s epitaxial quality (40%reduction in phi rocking-curve width when lattice-matched).

11:00 AMPhase Decomposition: A Model for Ferroelectric FatigueL. Peng, L. Qiao, University of Science and Technology Beijing, China; T. Li,General Research Institute for Non-Ferrous Metals, China; D. Xie, TsinghuaUniversity, China; J. Cao*, University of Science and Technology Beijing, China

Perovskite oxide ferroelectric materials offer many great potential ap-plications in next generation nanoelectronics such as ferroelectricgeneral memories and field-effect logic devices, owing to theirbistable polarization. Conversely, such applications put forward strictreliability requirements for the ferroelectric components. Polariza-tion fatigue is the most challenging and important reliability issue forthe nanoscale ferroelectric devices. Actually, it has seriously hinderedthe full commercial realization of ferroelectric memories and the useof a class of good candidate materials into ferroelectric devices, suchas lead zirconate titanate (PZT). Enormous theoretical and experi-mental studies of excellent scientific quality have been carried outover the past years. However, no satisfactory solution for controllingfatigue in PZT thin films with metal electrodes has been reported. Sofar no practical products using the two ferroelectric polarizationstates have reached a full commercialization satirically. In the presentstudy, the effects of fatigue and thermal annealing treatments on thefatigue properties of lead zirconate titanate (PZT) thin film capaci-tors with Pt electrodes were investigated. The polycrystalline PZTthin films were prepared on Pt/TiOx/SiO2/Si substrates by a chemicalsolution deposition method. Based on the results, a new mechanismof phase decompositions in the ferroelectric films as well as at the fer-roelectric/electrode interfaces was put forward.

11:20 AMDirect Measurements of Individual Domain Nucleation andGrowth Dynamics with <20 nsec Temporal Resolution per PixelR. Nath, N. Polomoff, J. Bosse, A. Lucas, B. D. Huey*, University ofConnecticut, USA

High Speed Scanning Property Mapping allows full frame, full reso-lution, AFM-based images to be continuously acquired in less than 1second each. Applied to ferroelectric thin films during in-situ biasingbeyond the coercive field, the spatial and temporal development ofdomain switching can thus be uniquely mapped. Following Avramimodels, the energetic distribution of nucleation and growth rates canalso be determined. Results are compared for area switching as in FE-

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 228

Th

urs

day

AM

www.matscitech.org 229

capacitors, as well as for the individual domains within. Resolutionbelow 20 nm spatially and 16 nsec temporally is achieved.

Electronic & Magnetic Materials:Ferroelectrics and Multiferroics

Physical Properties and Nanoscale Phenomena Room: 318Session Chair: Sharmila Mukhopadhyay, Wright State University

8:00 AMSelf-Assembled Epitaxial Multiferroic Nanocomposite FilmsPrepared by Polymer-Assisted Deposition (Invited)H. Luo*, H. Yang, S. A. Baily, O. Ugurlu, M. Jain, M. E. Hawley, E. Bauer, T.McCleskey, A. K. Burrell, L. Civale, T. G. Holesinger, Q. X. Jia, Los AlamosNational Laboratory, USA

Multiferroic materials, which show simultaneous electric and mag-netic ordering, have attracted considerable interest recently due totheir unusual physical properties and potential device applications.Magnetoelectric (ME) coupling between electric and magnetic orderparameters has been observed in some single-phase compounds, aswell as composites of either horizontal multilayer heterostructures orself-assembled vertical heterostructures. In this talk, we describe achemical solution technique, polymer-assisted deposition (PAD), togrow self-assembled epitaxial multiferroic nanocomposite BaTiO3-NiFe2O4 and SrTiO3-CoFe2O4 thin films. This technique employsmetal ions coordinated with soluble polymers with the desired vis-cosity as film precursors. The polymers actively bind the metal ions toensure a homogeneous metal ion distribution and prevent unwantedreactivity. The structural and transport properties of these nanocom-posites will be discussed in detail in this presentation.

8:40 AMStructure-Property Relationships in Sodium-Potassium NiobateCeramicsM. A. Cottrell*, University of Florida, USA; J. Daniels, European SynchrotronRadiation Facility, France; J. L. Jones, University of Florida, USA

Many electromechanical ceramics contain lead, which is known to betoxic to the environment. Therefore, there is a demand for lead-freematerials with similar properties, such as sodium-potassium niobate(NKN) based ceramics. Dopants are used to enhance properties, inour case by shifting the solid state phase transition temperature closerto room temperature. A direct method can be used to measure thephase transition by taking X-ray diffraction patterns as a function oftemperature. Such a method can complement indirect methods suchas dielectric measurements. Utilizing the facilities at the EuropeanSynchrotron Radiation Facility (ESRF) and our laboratory X-ray dif-fractometer, we were able to measure the solid state phase transitiontemperatures as a function of dopant type. The orthorhombic totetragonal phase transition is lowered from ~190°C to ~70°Cthrough the addition of a lithium-antimony dopant.

9:00 AMPoling of Piezoelectric Ceramics (Invited)T. Granzow*, Technische Universität Darmstadt, Germany; A. B. Kounga,EPCOS OHG, Austria; T. Leist, J. Rödel, Technische Universität Darmstadt,Germany

The properties of ferroelectric ceramics for piezoelectric applica-tions strongly depend on the domain structure resulting fromelectrical poling. Both too little and too much domain orderstrongly diminishes the piezoelectric response. In this talk, the in-fluence of different poling procedures on the piezoelectric proper-ties of lead-zirconate-titanate (PZT) ceramic will be presented anddiscussed with respect to the domain structure. High polarizationcan be obtained by field-cooling under comparably low fieldsthrough the paraelectric-ferroelectric phase transition; however, a

threshold field exists below which optimum polarization is notpossible. This behavior is traced to depolarizing fields appearing atgrain boundaries during the transition. Applying a mechanicalload perpendicular to the field direction also leads to a drastic re-duction in the field required for poling due to the coupling of fer-roelastic and ferroelectric properties. This technique allows the ef-ficient poling of materials with high coercive field or leakagecurrents.

10:00 AMDoping of BiScO3-PbTiO3 Ceramics for Enhanced ResistivityA. Sehirlioglu*, Case Western Reserve University, USA; A. Sayir, F. Dynys,NASA Glenn Research Center, USA

High-temperature piezoelectrics are a key technology for aero-nautics and aerospace applications such as fuel modulation to in-crease the engine efficiency and decrease emissions. The principalchallenge for the insertion of piezoelectric materials is the limita-tion on upper use temperature which is due to low Curie-Temper-ature (TC) and increasing electrical conductivity. BiScO3-PbTiO3(BS-PT) system is a promising candidate for improving the oper-ating temperature for piezoelectric actuators due to its highTC(>400oC). Effects of Zr and Mn doping of the BS-PT ceramicshave been studied and all electrical and electromechanical proper-ties for Sc-deficient and Ti-deficient BS-PT ceramics are reportedas a function of electrical field and temperature. Donor dopingwith Zr and Mn increased the DC-resistivity and decreased tanδat all temperatures. Resulting ceramics exhibited saturated hys-teresis loops with low losses and showed no dependence on theapplied field (above twice the coercive field) and measurementfrequency.

10:20 AMSr modified PCBN ceramics for piezoelectric and pyroelectricapplicationsK. Ramam*, University of Concepcion, Chile; K. Chandramouli, AndhraUniversity, India

In this investigation, Sr modified PCBN ceramic compositions (Sr =0, 0.2, 0.4, 0.6, 0.8 and 1 mol%) were fabricated through solid statereaction method and characterized for dielectric, piezoelectric andpyroelectric properties. The influence of Sr on tungsten bronzestructured PCBN phase modification has been discussed with lat-tice parameters, tolerance factor and electronegativity. The dielec-tric, piezoelectric and pyroelectric properties as a function of Srconcentration has been evaluated for possible sensor and actuatorapplications.

10:40 AMCompeting Effects of Cu Ionc Charge States on Ferromagnetism inCu co-doped (ZnCo)O NanoparticlesM. Khan*, S. K Hasanain, Quaid-i-Azam University, Pakistan

We report the effects on the ferromagnetism due to co-doping ofZnO with Co and Cu in the presence of variable numbers of oxygenvacancies. The Co+2 ions are determined to be in the +2 state in atetrahedral symmetry, with no evidence for metallic Co or Cu, as de-termined by XPS and XANES. However ionic state of Cu is found tobe change from +2 to +1 state with increasing Cu concentration,which appears to strongly decrease the concentration of oxygen va-cancies. It is found that the ferromagnetic moment initially increaseswith the addition of Cu but decreases above a typical concentrationthat coincides with the appearance of Cu+1 state and the decrease ofO vacancy concentration. It is concluded that the effect of Cu in thevery low range of concentrations, where it appears to go in as Cu+2, isto stabilize FM indirectly i.e. via generation of O vacancies. The ef-fects of O vacancy concentration on the FM are interpreted in thelight of the F-center exchange (FCE) model.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 229

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania230

Electronic & Magnetic Materials: LowTemperature Processing for Integration ofMicroelectronics Devices

Direct Write IntegrationRoom: 319Session Chair: Yoshihiko Imanaka, Fujitsu Laboratories Ltd.

8:00 AMLow Temperature Sintering of Patterned Nanostructured SilverProduced by Laser Ablation of Microparticle Aerosols (Invited)A. D. Albert, P. D. Ferreira, M. F. Becker, J. W. Keto, D. Kovar*, University ofTexas at Austin, USA

The Laser Ablation of Microparticle Aerosol (LAMA) process pro-vides a method for generating high yields of nanoparticles (NP).When combined with an aerosol deposition process, LAMA can beused to produce patterned nanoparticulate films. In this study we ex-plore the influence of gas type and annealing temperature on the mi-crostructure and properties of patterned Ag lines. SEM, TEM, X-raydiffraction and electrical conductivity measurements were used todetermine the density and grain size of the films. Consistent with the-ory, lines with finer grain sizes (16 nm) and higher densities wereproduced with He buffer gas compared with Ar. Post-deposition an-nealing of the lines resulted in significant coarsening but little densi-fication at temperatures of 100-175°C. Introducing pressure duringannealing did not significantly influence the sintering kinetics for thefilms. In situ TEM was used to elucidate mechanisms for pressurelesssintering at low temperatures.

8:40 AMConductor Edge Definition Influence on High FrequencyElectrical LossT. S. Vincent*, I. Bar-On, WPI, USA

This study tests the theory that the edge definition of a thick-filmprint conductor can alter high frequency loss characteristic. High fre-quency loss degrades both GHz analogue and fast switching digitalsignals. A telecommunication system contains transmission linesconsisting of a conductor strip, that carries signals in the form ofelectromagnetic (EM) waves. This strip of conductor on the surfaceof a ceramic substrate acts as a guide to the EM signal and results inconductor loss; this the largest loss factor. As the frequency increases,the current concentrates closer to the conductor extremities espe-cially at the conductor edge. The ceramic surface, in particular sur-face roughness, can influence the topography of the conductor stripwhen the conductor is formed by thick-film processing. Using AlNand LTCC, with known surface characteristics, the edge definition forseveral conductors is measured and correlated to loss over a range offrequencies.

9:00 AMLow-Temperature Maskless Mesoscale Materials AerosolDeposition (M3D) of Oxides from Precursors and Suspensions(Invited)B. P. Gorman*, University of North Texas, USA

Low-temperature, direct-write processing of mesoscale 2-D and 3-Dstructures has recently been made possible through the use of aerosoldeposition techniques such as M3D (Optomec, Inc.). In this process,aerosols are generated from a solution or suspension with a viscositylower than 5000cps. Using this technique, we have been able to de-posit a variety of oxides for photovoltaics, display, and fuel cell appli-cations using polymeric precursor and particle suspensions. By tai-loring both the polymer chemistry (and thus the precursor viscosity)as well as the M3D operating parameters, ZnO lines could be de-posited at temperatures between 70 and 250°C with line widths be-tween 5 and 200μm at a speed of 1cm/s. Line thickness (conductance)

of the deposited lines can be increased by loading the precursor withcolloidal particles. Tailoring the substrate surface chemistry forproper wetting of the precursor solvent enables more narrow andparallel lines to be written.

10:00 AMLow Temperature Curing of Printed Electronic Conductors andDielectricsJ. W. Sears*, M. Carter, South Dakota School of Mines & Technology, USA

Photonic curing technology allows for room temperature curing(sintering) of nanoscale ink particles into functional components.This technology cures printed nanoscale inks to produce patterns onlow-temperature substrates including flexible circuit boards, flatpanel displays, interconnects, RFID tags, and other disposable elec-tronics through the use of a controlled flash of light. This paper re-ports on the results obtained after sintering conductive, magnetic,and dielectric nano-particle inks. The results obtained with the pho-tonic curing technique are compared to those obtained using a 2Wfrequency doubled Nd:YAG CW laser, and a conventional muffle fur-nace. These results include: sample thickness and density, microstruc-tural analysis, and electrical resistivity. Examples of passive electricaldevices produced through photonic curing will be presented.

10:20 AMDense Yttrium Oxide Film Prepared by Aerosol Deposition atRoom Temperature (Invited)J. Iwasawa*, R. Nishimizu, H. Ashizawa, TOTO LTD., Japan

Dense yttrium oxide film was prepared by aerosol deposition processat room temperature. The deposition rate was much higher than thatattained by conventional coating techniques. Thick film of over 10micron was easily achievable on various substrates such as aluminumalloy, alumina, and quartz with this process. A usable coating area was600 mm x 600 mm. Cross-sectional electron microscopy showed thatthe film was highly dense without voids and had a homogeneous in-terface between the film and the substrate used. The film was ran-domly oriented Y2O3 crystallites of size smaller than 20 nm. The in-fluence of plasma exposure in a gas mixture of CF4/O2 on the surfaceof the film, namely, erosion rate, surface roughness, and nanostruc-ture was examined. Furthermore, we compared the plasma resistanceof the film with that of conventional materials. The film had an excel-lent plasma resistance.

Electronic & Magnetic Materials: PerovskiteOxides: Films, Nanostructures, Properties,and Applications

Heterostructured Perovskite OxidesRoom: 316Session Chairs: Menka Jain, Los Alamos National Laboratory; LaneMartin, Lawrence Berkeley National Laboratory

8:00 AMEngineering New Functionalities with Multiferroics: ElectricalControl of Magnetism (Invited)L. W. Martin*, Lawrence Berkeley National Laboratory, USA

Magnetoelectric multiferroics have piqued the interest of researcherswith the promise of coupling between magnetic and electric orderparameters. An excellent example of this is BiFeO3 (BFO), a system inwhich there is direct and controllable coupling between antiferro-mangetism and ferroelectricity. Armed with materials like BFO, re-searchers can begin to create new types of functionality that stand torevolutionize the next generation of devices. In this talk I will explorehow one can utilize the coupling between ferroelectricity and antifer-romagnetism (magnetoelectricity) and the coupling between an anti-ferromagnet and a ferromagnet (exchange coupling) to achieve elec-

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 230

Th

urs

day

AM

www.matscitech.org 231

tric field control of ferromagnetism at room temperature. Growthand extensive characterization of model ferromagnetic/multiferroicthin film heterostructures will be presented. Magnetic properties, themechanism of coupling, and evidence for dynamic switching of fer-romagnetism at room temperature will be presented.

8:40 AMDirect Measurement of the Low-Temperature Spin-StateTransition in LaCoO3R. F. Klie*, G. Yang, Y. Zhao, University of Illinois at Chicago, USA

The perovskite oxide LaCoO3 exhibits an anomaly in its magneticsusceptibility around 80 K associated with a thermally excited transi-tion of the Co3+-ion spin. Here, we will show that atomic-resolutionZ-contrast imaging and electron energy-loss spectroscopy can be uti-lized to measure the spin-state transition in Co-based perovskite ox-ides. In particular, we utilize in-situ cooling experiments in a trans-mission electron microscope to demonstrate that the O K-edgepre-peak is sensitive to the Co3+-ion spin-state in LaCoO3. Our ex-perimental results will be compared to first-principles calculations,and we will conclude that the thermally excited spin-state transitionoccurs from a low to an intermediate spin state, which can be distin-guished from the high-spin state. Finally, we will examine the effect ofbi-axial strain and point defects in LaCoO3 thin-films on the Co3+-spin state, and suggest a novel approach to stabilizing the differentspin states in LaCoO3 at room-temperature.

9:00 AMFerroic Epitaxial Oxide Thin Films and Heterostructures (Invited)B. Wessels*, Northwestern U, USA

We have been investigating the synthesis of epitaxial multilayeredstructures of ferroic oxides by oxide molecular beam epitaxy that po-tentially exhibit novel magnetic, magneto-optical and magnetoelec-tric properties. The magnetic oxides of interest are ferrite spinels thatinclude Fe3O4, MgFe2O4, and CoFe2O4. Epitaxial layers are de-posited on the perovskites SrTiO3 and BaTiO3. Since the ferrites arenot isostructural with perovskites and there is considerable misfitstrain, the film properties are sensitive to deposition conditions.Nevertheless epitaxial ferrite layers with magnetic properties ap-proaching that of the bulk have been deposited. Of particular inter-est is Fe3O4, which has a Curie temperature of 860 K and a half-metallic state leading to spin polarization. An all oxide epitaxial het-erojunction of Fe3O4 on Nb:SrTiO3 that shows excellent rectifica-tion has been demonstrated. These oxide junctions show consider-able promise for spin injection devices for spintronic andmagnetoelectric applications.

9:40 AMPerovskite Oxides: Recent Trends (Invited)B. Raveau*, CRISMAT, France

Perovskite oxides represent a vast family of materials susceptible togenerate fascinating properties in view of applications. Starting fromtheir stoichiometric ABO3 composition, one can generate structuraldistortions, mixed valency of B elements, ordered and disorderedoxygen non stoichiometry and intergrowths with closely relatedstructures. Besides the well known family of high Tc superconductingcuprates, manganites and cobaltites present a great potential for thegeneration of new magnetotransport properties, such as colossalmagnetoresistance (CMR), but also complex magnetic and electricaltransitions, charge-orbital ordering and phase separation phenom-ena. Recent developments in this field will be presented, taking as ex-amples Ln1-xAxMnO3 and Sr1-xLnxCoO3-d perovskites, orderedoxygen deficient perovskites such as LnBaM2O5.50 (M=Mn,Co) andordered stoichiometric perovskites LnBaM2O6 (M=Mn,Co). Recentresults concerning multiferroic properties of manganite perovskitescontaining trivalent bismuth will also be discussed.

10:20 AMMagnetotransport properties of the Pr0.5Ca0.5MnO3 thin filmgrown by a solution techniqueM. Jain*, F. Ronning, J. D. Thompson, L. Stan, Q. X. Jia, Los Alamos NationalLaboratory, USA; J. Yoon, H. Wang, Texas A&M University, USA; C. B. Eom,University of Wisconsin, USA

Chemical solution deposition technique was used to grow epitaxialPr0.5Ca0.5MnO3 films on (001) LaAlO3 and (001) SrTiO3 substrates.The zero field resistivity of the films showed semiconducting behav-ior. In the resistivity and magnetization measurements, a characteris-tic of charge-ordering was observed at 220K and 230K, for the film onLAO and STO, respectively. Melting of charge-ordering was observedwhen magnetic field was applied perpendicular to these films. At anapplied magnetic field of > 5T, the resistivity of the films reduced sev-eral orders of magnitude at low temperatures (< 100K) and hencemagnetoresistance of nearly -100% was observed at 75K. Structural,microstructural, and magnetotransport results of these films will bepresented in detail.

10:40 AMStrain Relaxation of BaTiO3 Thin Films Grown on Small Lattice-Mismatched Substrates (Invited)X. Pan*, University of Michigan, USA

Strain in epitaxial thin films can be controlled by carefully choosingthe structure and orientation of substrates and/or epitaxial buffer lay-ers with suitable lattice constants and thermal expansion coefficients.The interface structure, dislocation configuration, and strain relax-ation in bi-layer systems are different from those in single layer sys-tems. In this paper we studied the strain relaxation in epitaxial BaTiO3films grown on small lattice-mismatched substrates (GdScO3, DyScO3and SrTiO3) with strained/partially relaxed SrRuO3 bottom electrodes.Interfacial structure and strain relaxation of BaTiO3/SrRuO3 bilayerswith different thicknesses in each layer were investigated by TEM. Theexperimental results were explained by thermodynamic theory and ki-netic considerations. We found that the different strain relaxation be-haviors observed in the bilayer are mainly dependent on lattice mis-match of each layer to the substrate and the thicknesses of each layer.

Environmental & Energy Issues: Frontiersin Materials Science: Closing the NuclearFuel Cycle

Nuclear Fuel ManagementRoom: 326Session Chair: Ramana Reddy, University of Alabama

8:00 AMThe Global Nuclear Energy Partnership (GNEP) - An OverviewJ. Marra*, Savannah River National Lab, USA

The United States Department of Energy (DOE) launched the GlobalNuclear Energy Partnership (GNEP) in 2006 as an integral parts ofthe Department’s plan to revitalize the nuclear industry. The GNEPprogram has the ambitious goals to advance nuclear energy in the USand across the globe in a manner that makes use of advances in tech-nology. Specifically, these advances reduce the proliferation concernsassociated with nuclear energy and minimize wastes associated withnuclear processes. This presentation describes the GNEP programand discusses the important role that the materials community willplay in the nuclear renaissance.

8:20 AMCandidate Alloy System for a GNEP Metallic WasteformM. Kane*, R. Sindelar, Savannah River National Laboratory, USA

The GNEP waste management program aims to minimize waste vol-ume and to form a stable waste form for high level radioactive waste

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 231

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania232

from the various process streams. The GNEP Integrated Waste Man-agement Strategy document has identified a Zr-Fe metallic wasteform (MWF) as the baseline alloy for disposal of Tc metal, undis-solved solids, and TRUEX fission product wastes. However, the highprocess temperature (1600°C) for a Zr-Fe alloy would challenge off-gas systems and throughput. A modified alloy, Zr-Cu-Fe, is being in-vestigated to reduce the process temperature and enable high wasteloadings in a stable waste form. This alloy has been characterizedusing SEM/EDS, XRD, DSC, and corrosion tested using linear polar-ization resistance. Initial work to incorporate waste stream elementsinto the baseline alloy has been performed. Phase assemblage andspecie partitioning of Re metal (surrogate for Tc) and noble metal FPelements into the phases, and their corrosion resistance in various pHsolutions are reported.

8:40 AMGlass Formulation Development and Testing for Lanthanide andFission Product WastesJ. Marra*, A. Youchak, Savannah River National Laboratory, USA; J. Vienna, J.Crum, Pacific Northwest National Laboratory, USA

The Global Nuclear Energy Partnership (GNEP) waste managementstrategy revolves around specific treatment of individual or groups ofseparated waste streams. A goal for the separations processes is tominimize the amount of waste to be dispositioned as high level ra-dioactive waste. In the UREX+1a separation process, the fission prod-uct waste streams emanate from two major sources: raffinate fromTRUEX (non-rare earth element fission products); and TALSPEAKproduct containing lanthanides and yttrium. Testing was completedto develop waste glasses for the TALSPEAK only stream and the com-bination of the TRUEX raffinate and the TALSPEAK stream. Candi-date compositions were formulated and tested in an iterative processto identify optimal glass compositions. Glasses with waste loadingson an oxide basis of greater than 60 wt % for the TALSPEAK onlystream and greater than 25 wt % for combined stream were devel-oped. These glasses readily met known processing and product qual-ity constraints.

9:00 AMGlasses for Immobilizing Grouped Fission ProductsJ. V. Crum*, J. D. Vienna, Pacific Northwest National Lab, USA

A series of glasses were formulated for the immobilization of two po-tential waste streams from commercial nuclear fuel reprocessing – 1)the combined lanthanide (LN), alkali, and alkaline earth (Cs/Sr) fis-sion products, and 2) the combined LN/Cs/Sr with transition metalfission products (TRUEX raffinate) added. These glasses were formu-lated to meet repository disposal requirements while being process-able in a cold-crucible melter. The glasses were fabricated and testedfor product consistency test response, phase characterization, density,and glass transition temperature. The results suggest that the com-bined fission product waste forms are sufficient to meet current re-quirements and would be more efficient than fabricating and qualify-ing waste forms for individual fission product streams.

9:20 AMOverview of Materials Issues for Fusion Power PlantsR. J. Hanrahan*, National Nuclear Security Administration, USA

Over fifty years of research has brought us incrementally closer toachieving controlled nuclear fusion. Several different approaches arecurrently being pursued. Magnetic confinement fusion, laser driveninertial confinement fusion, and pulsed power inertial fusion ma-chines are all being built and operated. Since the goal of achievingburning plasma producing a net yield of energy has still never beenachieved; the materials issues for fusion power have received relativelylittle attention. The majority of materials development that has beenconducted was focused on the materials for targets, magnets, and firstwall materials. These will not be discussed here. The topic of this

presentation will be the materials issues for energy conversion sys-tems and the balance of plant.

9:40 AMA mechanism of non-equilibrium grain boundary segregation forintermediate temperature brittleness in metalsT. Xu*, K. Wang, Central Iron & Steel Research Institute, China

The graphical representation of non-equilibrium grain segregation ofimpurity offers a clear solution to an outstanding fundamental scien-tific mystery, intermediate temperature brittleness in metals, a prob-lem which leading researchers in the field have struggled to explainfor the past 100 years. For the elevated temperature tension tests ofmetallic materials a test temperature must exist at which a concentra-tion peak of non-equilibrium grain boundary segregation of impu-rity and a relevant ductility minimum occur and the test temperaturehas a critical time of non-equilibrium grain boundary segregation ofimpurity to be equal or close to the test isothermal time at this ten-sion test temperature. A number of diverse experimental results froma number of different labs can be rationalized on the new mechanismof intermediate temperature brittleness suggested in present paper.

Environmental & Energy Issues: Fuel Cells:Materials, Processing, Manufacturing,Balance of Plant and Systems Operation

Manufacturing, Balance of Plant, ModelingRoom: 325Session Chairs: Ayyakkannu Manivannan, National EnergyTechnology Lab; Z. Gary Yang, Pacific Northwest National Lab

8:00 AMDurability and Suitability of Fe-Cr-Nb(-Ti) Base Ferritic StainlessSteels for SOFC Interconnect ApplicationsZ. Yang*, G. Xia, Z. Nie, J. Templeton, L. Li, C. Wang, J. Stevenson, P. Singh,Pacific Northwest National Lab, USA; J. Rakowski, Allegheny Ludlum, USA

Ferritic stainless steels are among the most promising candidate ma-terials for interconnect applications in intermediate-temperature pla-nar SOFC stacks. In particular, newly developed alloy compositionsdemonstrate improved properties relevant to the interconnect appli-cations over traditional ones. However, for further cost-reductionthat would help accelerate commercialization of the SOFC technol-ogy, it is desirable to find more cost-effective alternatives for the ap-plications. As thus Fe-Cr-Nb(-Ti) base stainless steels, e.g. 441, havebeen systematically investigated in both short- and long-terms underSOFC operating conductions. Surface modification via newly devel-oped, optimized protect layers have been applied for further im-proved performance. This paper will present details of this work anddiscuss durability and suitability of the bare and coated Fe-Cr-Nb(-Ti) base ferritic stainless steels for SOFC interconnect applications.

8:20 AMAnode supported SOFC fabricated by tape casting and co-sintering of anode and electrolyteM. Gong*, X. Liu, Y. Jiang, C. Xu, J. Zondlo, West Virginia University, USA; C.Johnson, R. Gemmen, National Energy Technology Laboratory, USA

Developing of high-performance solid oxide fuel cell (SOFC) by low-cost manufacturing methods has received up-surging interest forpower generation. An industrially-robust and cost-effecitve fabrica-tion method for anode-supported planar SOFC has been developedby tape casting and co-sintering of yttria-stabilized zirconica (YSZ)electrolyte and Ni-YSZ anode at 1400~1450°C followed by screenprinting and sintering of strontium doped lanthanummanganate(LSM)-YSZ based cathode. Performance of anode-sup-ported SOFC was promoted by addition of Ni-YSZ and LSM-gadolinium doped ceria(GDC)as anode and cathode activation layer.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 232

Th

urs

day

AM

www.matscitech.org 233

Cell test with air as oxidant showed peak power densities of 0.75 and0.82 W/cm2 respectively with 50%N2-50%H2 and 100%H2 as fuel at750°C, and 1.14 W/cm2 with 100%H2 as fuel at 800°C. V-I curve andAC impedance studies indicated superior electrode performanceachieved for anode activation layer with higher Ni content and betterstability at higher co-sintering temperature

8:40 AMThin-wall Ceramic Heat Exchangers for Solid Oxide Fuel CellsT. Briselden*, T. Reilly, D. Forsman, Penn State University The BehrendCollege, USA

The purpose of this study is to evaluate the design of thin wall ce-ramic heat exchangers for SOFCs that can operate at temperaturesexceeding 1000 °C with effectiveness greater than 60%. High surfacearea to volume ratio helical, spiral, and concentric tube heat ex-changer elements were fabricated using a thin-wall (less than 2.5mm)dry powder printing method. The devices were tested at temperaturesbetween 900 °C and 1100 °C at mass flow rates typical of energy de-vices operating between 10 kW and 50 kW. Specifically discussed is a100 mm and 178 mm diameter by 300 mm long helical silicon car-bide heat exchanger element produced with a surface area to volumeratio of 128/m. The element was tested at inlet Reynolds numbersranging from laminar thru transitional flow resulting in a 48% to69.2% effectiveness. The study findings demonstrate that complex,thin-wall ceramic heat exchanger elements can be manufactured inhighly effective shapes for SOFC applications.

9:00 AMEffect of solids loading and plasticizer content of concentratedzirconia inks for screen printing SOFC electrolyteJ. W. Phair*, A. Kaiser, Risø National Laboratory for Sustainable Energy,Denmark

Screen printing fabrication is attracting increasing interest for thelarge scale production of ceramic components for cutting edge tech-nologies, including solid oxide fuels cells (SOFCs) and oxygen separa-tion membranes. The present work investigates the effect of variablesolids loading and plasticizer content on the rheological properties ofzirconia inks for screen printing SOFC electrolyte. By assesing therheological properties of the inks using a cone and plate rheometer, itwas possible to correlate various rheological parameters to the com-position of the inks and their screen printing performance. Explana-tions for the effect of various compositional and rheological parame-ters on the screen printing performance of the inks are discussed andconclusions provided. Optimal plasticizer and solids loading com-postions were identified for the present ink system.

9:20 AMIn Situ Deformation of a SOFC Button Cell in Coal SyngasH. Guo*, R. R. Dastane, B. S. Kang, West Virginia University, USA

Coal syngas based Solid Oxide Fuel Cells are the future of effectiveand clean power generation. Over time SOFC performance degradesdue to high operating temperatures, thermal cyclic effects, syngas andcontaminants. The electrochemical degradation mechanisms are welldocumented but little work has been done in understanding the me-chanical degradation. This research aims at analyzing SOFCs in syn-gas at 800 degrees C by making simultaneous measurements of anodedisplacements and impedance spectroscopy. In a simulated syngasenvironment at 800 degrees, the impedance and the in-situ non-con-tact out-of-plane deformation of the anode will be measured byrecording the interferential fringe patterns at the Ni (or Pt) mesh cur-rent collector. Changes in fringe patterns, coinciding with changes insurface deformation due to changes in applied pressure will also berecorded. The anode will then be characterized using SEM, XRD andXPS to relate the structural integrity to the chemical composition andmicrostructure of the anode.

10:00 AMDevelopment and Investigation of (Mn,Fe,Co)3O4 ProtectionLayers on Ferritic Stainless Steels for SOFC InterconnectApplicationsL. Li*, G. Xia, J. Templeton, Z. Yang, J. Stevenson, P. Singh, Pacific NorthwestNational Lab, USA

In intermediate-temperature planar SOFC stacks, ferritic stainlesssteels are used as promising candidates for construction of intercon-nects that electrically connect neighboring cells and hermetically sep-arate fuel at the anode-side and air at the cathode-side. For furtherimproved surface and electrical stability, and prevention of Cr-poi-soning, the steel interconnects are required to be surface-modifiedwith conductive protection layers. In the past couple of years, PNNLhas been conducting this investigation and developing the protectionlayers, in particular of (Mn,Co)3O4 by and fabrication approaches.Our latest efforts have focused on modified coating chemistries andoptimization of fabrication process for further cost reduction andquality improvement. This paper will give an update on our efforts inthis area.

10:20 AMThe performance of solid oxide fuel cells (SOFC) withelectroplated interconnect as cathode current collectorJ. Wu*, West Virginia Univ., USA; R. S. Gemmen, C. D. Johnson, NationalEnergy Technology Lab, USA; Y. Jiang, West Virginia Univ., USA; X. Liu,National Energy Technology Lab, USA

Due to chromium poisoning effect, SOFC performance always de-grades quickly with metallic interconnects. One of the most effectivemethods is to add coating on interconnect to prevent Cr diffusionand retain high conductivity. (Mn,Co)3O4 spinel is a promising coat-ing for interconnect application due to its high conductivity andgood chromium retention capability. Electroplating of alloys fol-lowed by oxidation offers a cost effective method to produce the de-sired spinels. Interconnect on button cell test is the most practicalmethod to evaluate the coating properties. In this study, pure Co andMn/Co alloys by electrodeposition are used to protect the substrate,SUS 430. Before test, both coatings are oxidized to spinel at 800C for2 hours. Cell power densities are monitored as a function of time.After the test, SEM/EDX and XRD are used to characterize the celland interconnect coatings. In addition, uncoated interconnect wasused as baseline for comparison.

10:40 AMPore-Scale Modeling and Toward Virtual Material Design inPolymer Electrolyte Fuel CellsP. P. Mukherjee*, C. Wang, Los Alamos National Laboratory, USA

In the present sustainable energy initiative, the polymer electrolyte fuelcell (PEFC) has emerged as a promising alternative energy conversion de-vice for different applications. Despite tremendous recent progress, a piv-otal performance limitation in the PEFC comes from the underlyingcompeteing transport mechanisms. The catalyst layer (CL) and the gasdiffusion layer (GDL) play a crucial role in the PEFC performance due tothe transport limitation in the presence of liquid water and flooding phe-nomena. In this work, we discuss the development of a comprehensivepore-scale modeling framework comprising of a stochastic microstruc-ture reconstruction model, a direct numerical simulation model and atwo-phase lattice Boltzmann model with the objective to gain insight intothe two-phase dynamics and intricate structure-transport-performanceinterplay in the CL and GDL.Finally the importance of a pore-scale mod-eling paradigm to enable virtual material design in PEFCs is elucidated.

11:00 AMChemical Fracture of a Ceramic Oxygen Ion Conductor withPeriodic Edge CracksZ. Jin*, Z. Fan, University of Maine, USA

This paper investigates multiple surface cracking in an oxygen ionconducting ceramic undergoing lattice expansion. We assume that

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 233

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania234

the cracks are parallel and periodically distributed, which allows de-tailed examination of the effects of multiple crack interactions aswell as analytical treatment of the problem. A singular integralequation method is used to calculate the chemical stress intensityfactor (CSIF) at the crack tips in the framework of linear chemo-elastic fracture mechanics. The effect of crack spacing or crack den-sity on the CSIF is examined using the numerical results for the pe-riodic cracks at the cathode side of a Gd-doped ceria under theconstrained flat conditions. It is found that the CSIF can be reduceddramatically by decreasing the crack spacing (or increasing thecrack density). Hence, the fracture resistance of ceramic oxygen ionconductors can be enhanced with high density multiple surfacecracks.

Environmental & Energy Issues: GreenTechnologies for Materials Manufacturingand Processing

Green Technology AnalysisRoom: 323Session Chairs: Tatsuki Ohji, National Institute of AdvancedIndustrial Science and Technology; Richard Sisson, WorcesterPolytechnic Institute

8:00 AMTeaching and Learning Green Engineering and EnvironmentalSustainability (Invited)R. D. Sisson*, J. O’Shaughnessy, J. A. Bergendahl, WPI, USA

Sustainable development is coverd in three courses in the engineer-ing curriculum at WPI. “Environmental Impacts of EngineeringDecisions”, is a course that is taught across department boundaries.Topics range from , energy generation and energy conservation,water conservation and reuse, global climate change, sustainability,and design decisions in the electronic and automobile industries.The second course is a graduate course in materials processing “Ad-vanced Materials Processes” that takes an in depth look at severalmaterials process in terms of sustainability and robustness, and im-pacts beyond the plant boundary. The third course is a combinedCivil / Mechanical graduate course “Green Engineering”. Group ori-ented assignments includes design of a simple product ”Toys orTools”, and marketing a new green product or service. This paperwill summarize the course contents, challenges, successes, and bar-riers encountered in the development and teaching of thesecourses.

8:40 AMApproaches to Minimal-Manufacturing for Sustainability(Invited)H. Kita*, National Institute of Advanced Industrial Science and Technology(AIST), Japan

The “Minimal Manufacturing” is defined as “the manufacture of thehighest performance products” through “minimal resource input”and “minimal energy use (in terms of manufacturing cost and envi-ronmental load),” while maintaining “minimal environmental load inthe disposal stage”. Under this concept, AIST (Japan’s largest researchinstitute) is trying to establish the technological base, which leads totomorrow’s industry innovation for the sustainable society. The lessthe amounts of used resources and wasted materials and energy are,the smaller the environmental burden is. However this most fre-quently suppresses sound developments of industry and economy,and consequently, our wealthy lives and affluent societies are sacri-ficed. For this reason, we have discussed the index of “the Minimum”considering competitiveness in economic activities and the specifictechnologies which would meet those conditions. This paper de-scribes the outline and achievements of these efforts.

9:20 AMApplication of Furnace Modeling Software to EnergyConsumption and SustainabilityY. K. Rong*, L. Zhang, P. Radhakrishnan, R. D. Sisson, Worcester PolytechnicInstitute, USA

Furnace modeling software has been developed and verified that pre-dicts the heating times and rates for each part in load that is beingheat treated in an industrial furnace. The inputs to this model in-clude the furnace characteristics as well as the part design and theload racking. The outputs of the model include temperature versustime for each part in the furnace load and energy consumption perpart or load weight. This model is easily used to determine best partloadings to minimize cycle time and/or energy consumption. Severalcase studies will be presented to demonstrate the effectiveness of thetechnique.

10:00 AMEngineering Decisions to Green the Automobile Supply ChainJ. Isaacs*, Northeastern University, USA; T. Seager, Rochester Institute ofTechnology, USA; J. Laird, Metaversal Studios, USA

Designed for in-class play by undergraduate, graduate engineering orbusiness students, the game structure is based on team competitionof companies in the automobile supply chain, with the game objec-tive set to achieve the highest profit and lowest environmental detri-ment. Students take on roles for each of the three companies in thesupply chain: materials, parts, and cars. Within ten rounds, each teamtakes its turn to invest and select among different technologies inthree areas: production, storage and waste disposal. There are trade-offs in investment costs and green values for each technology option,and there is a hierarchy to the innovation options available for eachturn. Successful game strategy requires both cooperation and compe-tition for players to succeed. Knowledge is gained along multiple di-mensions: environmental policies and legislation that influence man-ufacturing in the global economy; current strategies used to addressenvironmental burdens; tradeoffs and team-based decision-making.

10:20 AMEnvironmental Assessment of Manufacturing with CNTsJ. Isaacs*, L. Dahlben, Northeastern University, USA

Nanomanufacturing research for various applications has been un-derway, ranging from carbon nanotube (CNT) transistors to CNT-polymer composites. While these nanomanufacturing processes arestill in the developmental stage, it is critical to formulate an under-standing of their associated environmental footprints. Using life cycleassessment (LCA) – a methodology to explore the environmental im-pacts associated with a product’s life cycle – inventory for these CNTprocesses are acquired through data collection of inputs (raw materi-als, energy and equipment used) and outputs (emissions). A life cycleinventory for CNT composite processing has been developed, andsensitivity analyses were performed to investigate environmental at-tributes of the process. The process is assessed prior to full-scale man-ufacturing to determine possible alternatives that could be more en-vironmentally benign. The environmental attributes of CNTprocesses are of particular interest because of their uncertain envi-ronmental health and safety risks.

10:40 AMThe Analysis of Emissions Produced During Glass ManufacturingL. Jones*, Smith College, USA

The emissions profile associated with specific batch constituents isstudied during the decomposition of nitrate fining agents in a tubingglass batch. Fourier transform infrared of batch decomposition inUHP Ar and O2 is undertaken. An oxygen rich environment slowsthe decomposition. The initiation temperature for the decompositionof nitrate containing tubing glass batch in UHP Ar and O2 under thesame experimental conditions is 823 K (550°C). The NOx emission

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 234

Th

urs

day

AM

www.matscitech.org 235

species are identified to be NO (g), NO2 (g), and N2O (g) in both sit-uations. Nitrate decomposition in the tubing glass batch demon-strates higher concentration of NOx emissions than that of pure ni-trate decomposition. Additional batch constituents accelerate thedecomposition process and prompt the evolution of NOx emissionsby speeding up the rate determining step of the nitrate decomposi-tion which are KNO2 (l) Ç K(g) + NO2 (g) and KNO3 (l) Ç K(g) +NO3 (g) for path I and II respectively.

11:00 AMExergy Analysis on Life Cycle of Ceramic PartsH. Kita*, H. Hyuga, N. Kondo, T. Ohji, National Institute of AdvancedIndustrial Science and Technology, Japan

It is critically important to consider the value of a product in terms ofnatural resource consumption and environmental problemsthroughout its life cycle. In order to achieve this, we need a methodfor quantitative evaluation of natural resource consumption that issimilar to measurements of economic cost. In this regard, exergyanalysis is an effective measurement approach. Based on these con-siderations, we carried out an exergy analysis for ceramics in order toclarify the value of environmental impact reduction throughout theirlife cycles and to develop a design policy for a highly efficient ceram-ics production process. Analysis was conducted based on large ce-ramic heat-tubes used in aluminum casting, and the amount of ex-ergy used in the manufacturing process and the degree ofeffectiveness were evaluated. In addition, we estimated the reductionin environmental impact and in the use of natural resources in theproduction and usage stages when ceramic heat-tubes were used,compared to conventional steel heat-tubes.

11:20 AMEmission Estimate MethodsW. J. Fullen*, Boeing, USA

Determinations of emissions for certain chemical process operationsare often needed when 1) obtaining environmental permits, 2) plan-ning for pollution control equipment for new operations, 3) reactingto the impact of new environmental regulations or 4) assessing im-pact of possible equipment failure. Consequently, a substantial num-ber of chemical engineering calculations are needed to answer funda-mental questions of environmental pollution such as: 1) Where doesthe pollutant go? and 2) How fast does it get there? There are manydocumented methods that use best practices based on mass balancemeasures. However, there are occasions where simple mass balancescannot be conducted. Thus ostensible methods are needed to esti-mate emissions where mass balance techniques are not easily ob-tained. Several cases are presented here that illustrate the methods ofcalculation for actual aerospace conditions of operation and the re-sults of these method applications are summarized.

11:40 AMMaterials Information Technology for Eco Design and RestrictedSubstancesP. Coulter*, D. Cebon, Granta Design Ltd., United Kingdom

Controlling environmental impact and meeting regulations are criti-cal success factors for engineering enterprises. Materials informationis central to any response, because much of the environmental foot-print of products is embodied in their constituent materials and be-cause materials are increasingly subject to regulation. Engineers need:Accurate data on materials and processes - specifically, on ‘eco prop-erties’ and restricted substances; decision support tools to apply thisinformation in ‘eco design’; and ‘Product stewardship’ methodologiesthat model and minimize environmental impact throughout the life-cycle. Effective eco design demands that such solutions are inte-grated. This talk will review requirements for a strategic approach tosuch design, developed by an international Consortium of industrialpartners. The talk will discuss advanced tools to: Optimize carbonfootprint and energy efficiency; quantify and reduce energy use,

emissions, and wastes from manufacturing, maintenance, and dis-posal; avoid costs, delays, and end-of-life problems due to restrictedsubstances.

Environmental & Energy Issues: Materialsand the Climate Change Challenge

Materials and the Climate Change ChallengeRoom: 327Session Chair: John Halloran, University of Michigan

8:00 AMCarbon Materials from Fossil Fuel ThermolysisJ. W. Halloran*, Z. Guerra, A. Wiratmoko, G. Pioszak, A. E. Sall, University ofMichigan, USA

Fossil fuels can be used as hydrogen ores for CO2-free energy, andcarbon ores for carbon construction materials, or “hydrogen energywith carbon materials”: HECAM. Coal thermolysis produces coke-like solids, resins, and hydrogen- and methane-rich gas. Thermal de-composition of the thermolysis gas yields additional hydrogen fueland produces vapor deposited carbon materials of high potentialvalue. This paper concerns the production and properties of carbonmaterials as co-products of hydrogen manufacture. Fabricated car-bons from coal tar pitch and coke are significantly stronger than ordi-nary concrete or masonry, and could be used as a carbon-sequester-ing construction materials. We present conceptual designs forHECAM processes and products, technoeconomic analyses for hy-drogen and carbon manufacture, and early results on vapor depositedcarbons.

8:20 AMCarbon-based Construction Materials from Fossil FuelThermolysisA. Wiratmoko, G. Pioszak, A. E. Sall, J. W. Halloran*, University ofMichigan, USA

Using fossil fuels as hydrogen ores for clean energy and carbon oresfor strong materials avoids carbon dioxide production both by directfuel burning and by displacing cement-based materials, which have alarge carbon dioxide burden. This paper reports experimental dataand calculations on carbon-based construction materials producedfrom fossil fuel thermolysis. Strong and light carbon materials can beproduced from minimally processed coal thermolysis products (cokeand coal tar pitch). These are stronger and lighter than concrete orfired clay bricks. Based on strength data, we consider the impact ofcarbon construction masonry on the carbon dioxide emissions in theconstruction industry. Thermal decomposition of methane from coalthermolysis gases or from natural gas an produce potentially highvalue vapor-deposited carbons. We consider carbon deposition onhot char performs as a means of producing strong carbon-bondedcarbon materials during hydrogen production.

8:40 AMTechnoeconomic Analysis of the Production of Hydrogen Fuel andCarbon Materials from Fossil Fuel ThermolysisZ. Guerra*, J. W. Halloran, University of Michigan, USA

We present detailed technoeconomic analyses of coal thermolysisprocesses for the production of hydrogen and carbon materials. Formonetary costs, we assume a baseline process based on coke ovencosts models, and consider the production of merchant hydrogen forthe chemical market or electrical power produced from the hydrogenby combusion or by fuel cell plants. Costs are compared with conven-tional hydrogen production by steam reforming of natural gas. Modelparameters include coal and methane costs; value of solid carbonproducts; and potential cost of carbon dioxide emissions. For envi-ronmental costs, we compare carbon dioxide emissions and other en-vironmental burdens.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 235

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania236

9:00 AMBoeing Report: Development of Sustainable Biojet FuelJ. Ray*, S. A. Millett, Boeing, USA

Boeing will report the current state of development of biofuels foraviation as a sustainable green technology. The biofuel demonstra-tion flight in Feb 2008 of a Virgin Atlantic 747 was the first commer-cial flight of an alternative fuel processed from plant oils. This paperwill discuss the key criteria for the future of biojet fuels: (1) Source ofbiofuel candidates will be second-generation biofuels from non-foodcrops using new high efficiency biomass-to-fuel conversion technolo-gies; (2) production of acceptable sustainable biofuel to meet interna-tional and US jet fuel standards; (3) the need for material compatibil-ity with fuel pipelines; (4) biofuel testing requires collaboration withjet engine manufacturers; (5) and the study of long-term materialscompatibility testing that must be evaluated for routine use on com-mercial airplanes.

9:20 AMCO2 emission of Chinese cement industryD. Xu, H. Li*, J. Fan, Y. Chen, S. Yun, College of Material Science andEngineering, Xi’an University of Architecture & Technology, China

Attributed to the calcination of carbonate and fuel combustion in-volved in the manufacturing process, cement industry is called as theheavy CO2 emission industry. In this paper, a computation moduleused to calculate the CO2 emission from cement production was putforward, and the annual and accumulate emission of China cementindustry from 1950 to 2006 was estimated. The role of reutilizing in-dustrial solid wastes as concrete admixture acting in CO2 emissionwas evaluated.

Fundamentals & Characterization: CeramicSurfaces, Grain Boundaries and Interfaces

Thermodynamics, Kinetics and AtomisticsRoom: 301Session Chairs: Jian Luo, Clemson University; Manfred Ruhle, MPIfur Metallforschung

8:00 AMExploring the Crystallography of Grain Boundary MotionCoupled to Shear Deformation (Invited)V. A. Ivanov*, George Mason University, USA; J. W. Cahn, University ofWashington, USA; Y. Mishin, George Mason University, USA

Coupled motion of grain boundaries (GB), in which a shear stressapplied to a GB causes its normal motion, and normal motion pro-duces shear deformation of the region traversed by the GB, has beenestablished for metals and crystalline ceramics by experiments andmolecular dynamics (MD) simulations. Coupled motion was foundfor [001] symmetrical tilt GBs in Cu with shears related to the tiltangle. Different coupling modes with different shear deformationsand directions of motion can be explained and predicted by crystallo-graphically equivalent descriptions of the same GB. We explore theeffects on coupled motion produced by each of five characteristic an-gles of the GB and the shear direction. We report on new MD simula-tions for [112] tilt and mixed GBs in Al, where we found multiplecoupling modes for the same GB, depending on the angle of the ap-plied shear. We propose a general geometric theory of coupled GBmotion, based on the crystallography, which is consistent with ourMD results.

8:40 AMInterfaces in Zr-based, Glass Forming Alloys (Invited)D. Lewis*, H. McGee, Rensselaer Polytechnic Institute, USA

Good glass forming alloys are used to better understand the connec-tion between solute segregation, grain boundary structure, and the

wetting transition. It is known that the wetting transition in puremetals occurs near the melting point making experimental observa-tion difficult. We propose study of metallic glasses as a means to re-duce the onset temperature of the wetting transition. In this paper wepresent results for a series of Zr-based alloys fabricated by rapidquenching. Preliminary results on the characterization of grainboundary chemistry in both polycrystalline and recrystallized alloyswill be presented. These results will be used to determine the materi-als and experimental conditions best suited for further study of thegrain boundary wetting transition. The information necessary to linkthese results to models of phase equilibria will be discussed. Ulti-mately, this work will provide the framework for understanding theonset of the wetting transition in more complex alloys.

9:20 AMSurface dynamics of Highly Anisotropic Refractory Materials(Invited)S. Kodambaka*, University of California Los Angeles, USA

Refractory transition-metal nitrides are widely used as hard wear-and corrosion-resistant coatings, as diffusion-barrier layers, and inoptics. Performance of these films depends sensitively on the surfaceand interfacial morphologies. Understanding the morphological evo-lution of these material surfaces is essential for improving their ther-mal/chemical stabilities. In this talk, we will present in situ high-tem-perature (1000-1700 K) scanning tunneling microscopy (STM) andlow-energy electron microscopy (LEEM) studies of the kinetics oftwo-dimensional (2D) TiN island Ostwald ripening, surface step nu-cleation and growth, step fluctuations, and island shape evolutin on(001) and (111) TiN terraces. From the data, in combination withcontinuum models, we determine the rate-limiting mechanisms gov-erning the surface morphological evolution and extract orientation-dependent surface and step energies. *work done at University of Illi-nois with S.V. Khare, J. Bareno, V. Petrova, W. Swiech, I. Petrov, andJ.E. Greene.

10:00 AMFinite Element Simulation of Segregation at Complex Interfaces inDilute AlloysF. Tancret*, F. Fournier Dit Chabert, F. Christien, R. Le Gall, Université deNantes, France

The surface or grain boundary segregation of trace elements can haveimportant consequences in materials: adhesion of thin films andcoatings, catalytic activity, embrittlement by S in nickel alloys or by Pin steels, reinforcement by B in nickel alloys, etc. The kinetics of inter-facial segregation can be simulated by a finite element (FE) approach(Comsol software), by implementing Fick’s diffusion laws in the bulkand the Darken-DuPlessis equation at the interface. It can be used tosimulate segregation kinetics in non-isothermal conditions, and canbe coupled to macroscopic FE heat transfer calculations. The segrega-tion model is here adapted to the case of complex interfacial phe-nomena: (i) segregation of a single dilute species with an interactionparameter between solute and solvent, (ii) simultaneous segregationof two species with a site competition in the interface, and (iii) segre-gation of a single species at an interface between two phases. Resultsare compared to available data.

10:20 AMMicrostructural Studies on Solid Oxide Fuel Cell CathodeMaterialsL. Helmick*, S. Dillon, Carnegie Mellon University, USA; K. Gerdes, R.Gemmen, National Energy Technology Laboratory, USA; G. Rohrer, S.Seetharaman, P. Salvador, Carnegie Mellon University, USA

Internal microstructure, including interfacial characteristics, of solidoxide fuel cell cathodes can impact their performance and evolve overtime under high temperature and electrochemical loads. The typicalSOFC cathode has a complex three-phase structure: strontium-doped lanthanum manganese oxide (LSM), yttria-stabilized zirconia

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 236

Th

urs

day

AM

www.matscitech.org 237

(YSZ), and pores. To generate a fundamental understanding of thedriving forces for SOFC microstructural evolution, the three-phasematerial was divided into its 6 constituent systems, including denseYSZ, porous YSZ, dense LSM, porous LSM, dense LSM/YSZ, andporous LSM/YSZ. Samples were prepared using standard SOFCpreparation methods, annealed at several temperatures, and charac-terized using orientation imaging microscopy. In this presentation,we will discuss the quantitative steady state distribution of grainboundary normals and of misorientation angles at internal interfacesand address the role of pores in the microstructural evolution ofdense and porous YSZ compacts.

10:40 AMOrientation Relationships and Morphologies of Pt Precipitates inSapphireM. Santala*, University of California, Berkeley, USA; V. Radmilovic, LawrenceBerkeley National Laboratory, USA; R. Giulian, M. Ridgway, AustralianNational University, Australia; R. Gronsky, A. Glaeser, University ofCalifornia, Berkeley, USA

Orientation relationships (OR) of Pt inclusions in sapphire wereidentified and the morphology for each OR in this model metal-ce-ramic system was determined. Pt nanoparticles were formed in(0001) sapphire substrates by ion implantation of 1×1016 cm–2 Pt fol-lowed by annealing at 1000°, 1200°, or 1600°C. Substrates were char-acterized by Rutherford backscatter spectroscopy, x-ray diffraction,and transmission electron microscopy. Depending on the implanta-tion temperature (room or liquid N2 temperature), substrates wereeither damaged or completely amorphized in the implanted region.During annealing, the amorphized alumina formed θ-alumina beforeconversion to α-alumina and precipitates at 1000° and 1200°C had(111)Pt||(0001)sapphire and interfaces bound by (111)Pt and (0001)sap-

phire. If no θ-alumina formed during processing, precipitates formedwith (110)Pt||(0001)sapphire and lacked interfaces bound by (0001)sap-

phire; this OR persisted at 1600°C and may be the equilibrium OR inthis temperature range.

11:00 AMAsymmetric tilt grain boundary structure and energy in copperand aluminumM. Tschopp*, Air Force Research Laboratory (UTC), USA; D. L. McDowell,Georgia Institute of Technology, USA

Atomistic simulations were employed to investigate the structure andenergy of asymmetric tilt grain boundaries in Cu and Al. In this work,we examine the Σ5 and Σ13 systems with a boundary plane rotatedabout the <100> misorientation axis, and the Σ3, Σ9 and Σ11 systemsrotated about the <110> misorientation axis. A simple energy rela-tionship based on faceting into the two symmetric tilt grain bound-aries describes several of these CSL systems, while the interface struc-ture in the Σ9 and Σ11 systems rearranges such that low index {111}and {110} planes bound the interface region. Last, the implications ofinterface structure on inelastic properties is also presented.

11:20 AMBoundary Structural Transition and Grain Growth Behavior inBaTiO3 by A-Site-Donor-Doping and Oxygen Partial Pressure ChangeS. An*, B. Yoon, S. L. Kang, Korea Advanced Institute of Science andTechnology, South Korea

The structural transition of grain boundaries in BaTiO3 and relatedgrain growth behavior have been investigated with changing A-site-donor concentration and oxygen partial pressure. A correlationamong vacancy concentration, grain boundary structure and graingrowth behavior has been found. When the total vacancy concentra-tion is low under a low oxygen partial pressure or under a high oxy-gen partial pressure with low donor concentration, grain boundarieswere well faceted and abnormal grain growth occurred in the pres-ence of {111}-twin lamellae. However, as the total vacancy concentra-tion increased with the addition of donor dopant or reduction of

oxygen partial pressure, the grain boundary structure changed fromfaceted to rough and abnormal grain growth was suppressed. The ob-served change in grain growth behavior was explained in terms of thechange in boundary mobility with boundary structure, which was af-fected by the total vacancy concentration.

Fundamentals & Characterization: Discoveryand Optimization of Materials throughComputational Design

Mesoscale Modeling and Microstructural Evolution IRoom: 303Session Chairs: James Warren, National Institute of Standards andTechnology; Edwin Fuller, National Institute of Standards &Technology

8:00 AMHyperthermia Induction Modeling for Optically-ActiveNanoparticles (Invited)E. R. Fuller*, A. T. Durnford, W. Hatchett, National Institute of Standards &Technology, USA

Optical activation of gold-nanoshell particles with laser radiation inthe near-infrared spectrum provides a means to induce hyperthermiain a tumor while leaving the surrounding healthy tissue intact. Theprocedure entails two processes: (i) heating of the nanoshells via aplasmon resonance phenomenon and (ii) diffusion of the heat fromthe particles into the surrounding tissue. Both processes are influ-enced by the density and distribution of particles within the tumor.Additionally, tumor-scale modeling of thermal ablation efficacy re-quires effective properties of tissue containing particles. Little is knowabout these effective properties. Moreover, while the dependence ofplasmon resonance absorption on shell size and thickness is well doc-umented, the dependence of plasmon resonance heating onnanoshell density and shell defects is not as clear. We use mesoscalecomputer simulations to elucidate these two processes and to deter-mine effective system properties and responses of nanoshell particleensembles.

8:40 AMNumerical Modeling of Sintering, a Status Check (Invited)M. W. Reiterer*, Medtronic, Inc., USA; T. R. Hinklin, Sandia NationalLaboratories, USA

The mathematical description of sintering has been a goal since thefirst efforts were made in the 1950’s. These descriptions have evolvedfrom relatively limited idealized models into today’s much morecomprehensive and sophisticated models. Such models are needed toreliably predict and control the sintered microstructure and resultantproperties. Over the past 50 years, the experimental equipment andtechniques to characterize and analyze microstructures, determinemodeling parameters and to test/refine the models have evolved dra-matically, along with computers capable of implementing the in-creasingly complex and descriptive models. However, it is still verydifficult to precisely predict and control microstructure evolution,final geometry and resultant properties. Results of sintering simula-tions, employing four different approaches will be presented andcompared to a previously published survey of industry needs. Thetalk will conclude with a discussion on directions for further progressin sintering simulations.

9:20 AMPhase Field Simulation of the Morphology of EutecticSolidification in a Binary Alloy Containing EncapsulatedImpuritiesR. Arroyave, M. Park*, Texas A&M University, USA

AAn insoluble impurity, such as a particle or a bubble, submerged ina melt alloy and approached by an advancing eutectic solidification

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 237

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania238

front, may be captured by the front, affecting the morphology of eu-tectic growth. To investigate this problem, we use a recent model byKim et. al. [Journal of Crystal Growth 261 (2004) 135], and modify itto consider pinning effects due to extraneous insoluble phases. In thiswork, we focus on the morphology of eutectic growth adjacent to thebubble. Eutectic growth patterns after encapsulation of the bubble areinvestigated with a variety of eutectic lamellar pattern and particlesizes (relative to characteristic lamella spacing) along the bubbleboundary as well as behind the bubble. Effects of alloy thermody-namics, interface mobilities, interdiffusion coefficients as well asanisotropy are also investigated.

10:00 AMPhase Field Modeling of Complex Polycrystalline SolidificationMorphologies (Invited)L. Granasy*, G. Tegze, Brunel University, United Kingdom; T. Pusztai, L.Kornyei, G. I. Toth, Research Institute for Solid State Physics and Optics,Hungary

Recent advances we made recently in phase field modeling of poly-crystalline solidification will be reviewed. Polycrystalline patterns arepresent in a broad variety of systems including metal alloys, poly-mers, minerals, and have biological relevance as well. The fact thatsimilar polycrystalline patterns are observed in systems of very differ-ent nature suggests that a minimal model based on coarse-grainedfields, which neglects the details of molecular interactions, might beappropriate. The rationale for developing such coarse-grained mod-els is the current inability of fully molecular models to address theformation of large scale morphologies. Along these lines, we have de-veloped a phase field models of polycrystalline solidification that relyone (2D) or more (3D) orientation fields in representing crystallo-graphic orientation.

10:40 AMPhase Field Modeling: From Drug Delivery to Soldering (Invited)J. A. Warren*, W. Boettinger, D. Wheeler, NIST, USA; D. Saylor, FDA, USA

I will present research efforts to extend phase field models intoregimes seemingly outside the traditional purview of these models. Insome cases, additional physical effects need to be incorporated, whilein others, it is simply making the pleasant realization that the modelis applicable that is the crucial step towards making an impact. In par-ticular, we will examine two seemingly disparate cases where phasefield modeling has now enabled quantitative studies of systems of in-terest: a drug eluting cardiac stent and a Pb-free solder droplet react-ing with a substrate as it spreads. These two cases will nicely demon-strate how phase field modeling can be used to better understandsuch systems, determine the crucial quantities controlling their be-havior, and also illustrate where phase field models still fall necessar-ily short. If there is sufficient time, a discussion of the relationship todensity functional theories (phase field crystal) and the ongoingquestions posed by this line of study will also be explored.

11:20 AMQuantitative phase-field modeling of coarsening and grain growthin multi-component polycrystalline alloys (Invited)N. Moelans*, L. Vanherpe, A. Serbruyns, K.U.Leuven, Belgium; B. Rodiers,LMS International, Belgium

We have developed a phase-field formulation for grain growth inmulti-component alloys which allows us a high controllability of thenumerical accuracy. The model can distinguish between properties ofdifferent interfaces and describe arbitrary misorientation and incli-nation dependence of grain boundary energy and mobility. Phase sta-bilities are described with concentration dependent Gibbs energy ex-pressions. An efficient ‘bounding box’ algorithm implemented usingobject-oriented C++, is used to solve numerically the phase-fieldequations. The model has been applied to phenomena such as graingrowth and recrystallization in the presence of second-phase particles(Zener pinning), thermal grooving, grain growth in fiber textured

materials and diffusion controlled coarsening in lead-free solderjoints. The model formulation and recent simulation results will bediscussed in this presentation.

Fundamentals & Characterization: FailureAnalysis for Problem Solving

Modeling and SimulationRoom: 304Session Chairs: Amar Sabih, McGill Institute of Advanced Materials;Julian Raphael, C M Hoist

8:00 AMFinite Element Analysis of Unnotched Charpy Impact TestsD. Jeong*, US DOT/Volpe Center, USA; H. Yu, Chenga Advanced Solutions &Engineering, LLC, USA; J. Gordon, Y. Tang, US DOT/Volpe Center, USA

This paper describes nonlinear finite element analysis (FEA) to exam-ine the energy to fracture unnotched Charpy specimens under pen-dulum impact loading. An oversized, nonstandard pendulum im-pactor, called the Bulk Fracture Charpy Machine, was constructed toconduct studies to assess the fracture behavior of various tank carsteels. Comparisons between measured and calculated impact ener-gies are presented. Test data and FEA results also show the effect ofvarious factors on impact energy. These factors include striker radius,specimen thickness, and specimen material. Moreover, calculations offracture energy are carried out using FEA in conjunction with differ-ent material failure criteria. The FEA results using a failure criterionbased on the general state of stress in terms of triaxiality are shown toprovide excellent agreement with the experimental data.

8:20 AMFinite Element Models to Study the Internal Failure Mechanismsin Cold-Heading Process (Invited)A. Sabih*, J. Nemes, McGill University, Canada

To understand the complex interplay of material and process param-eters on the initiation and development of the internal failure withinthe adiabatic shear bands in cold-heading process, two finite elementmodels were developed and implemented within ABAQUS/Explicitfinite element package. The first model was used to simulate a onestage impact test which is used to establish new failure criteria to eval-uate the internal damage. The second model was developed to simu-late and improve the design of three-stage cold-heading processes ofan industrial bolt. These models were used to investigate the effect ofthe thermal, geometric and the material flow softening and hardeningmechanisms affecting ASB evolution leading to this internal failure. Acomprehensive validation process of the impact test model was per-formed by matching the predicted results of this model with the re-sults of similar impact tests and metallurgical investigation.

8:40 AMFracture of Inconel 718 Structure and Combined Two-back StressHardening modelS. Yun*, Agency for Defense Agency, South Korea

The fracture of Inconel 718 part is analyzed using finite elementmodel. The loss of integrity stems from large plastic deformation dueto severe thermal environment. The two-back stress kinematic hard-ening model is developed by combining the Armstrong-Frederickand the Phillips’rules. The two back stress model is incorporated withcontinuum damage mechanics to depict the internal damage evolu-tion. Thus, the present model depicts a wide range of deformationbehaviors by selection of a pertinent fractional factor. The J2 defor-mation theory is employed to realize the intensive plastic deforma-tion localization. It is noted that the deformation localization and thedamage evolution significantly depends on the dominant evolutionof the back. The damage evolution within a work piece is also ob-served to accelerate the deformation localization.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 238

Th

urs

day

AM

www.matscitech.org 239

9:00 AMModeling Dynamic Forces in Powered Chain Hoists (Invited)J. Raphael*, C M Hoist, USA

Arresting the motion of descending loads induces dynamic forces inpowered chain hoists. Factors that govern the evolution of theseforces are identified and examined. Modeling of the problem is donewith the methods of analytical dynamics and the resulting equationsof motion are solved in closed form so that functional relationshipsamong all problem variables can be easily seen.

9:20 AM3D image-based analyses of fatigue crack propagation in an Al-Mg-Si alloyP. Qu*, H. Toda, H. Zhang, Toyohashi University of Technology, Japan; L.Qian, Research Institute for Applied Mechanics, Kyushu University, Japan; Y.Sakaguchi, M. Kobayashi, Toyohashi University of Technology, Japan

An advanced in-situ 3D observation technique via synchrotron X-rayCT has been applied for studying 3D fatigue crack behaviors. We ob-served the complex crack morphology and identify many essentialfeatures of the crack and its propagation inside a material. We foundsome 3D crack behaviors occurred unexpectedly, such as the complexdeformation behaviors in the region where two crack segments lyingon different horizontal planes overlap each other slightly. To betterunderstand the fracture mechanisms of the observed phenomenon,an image-based numerical simulation method which takes into ac-count real crack morphology was performed to identify all key fea-tures of fracture that involves the evolution of local stress/strainfields, which were verified by 3D experimental investigation. Thecombined methodology of in-situ 3D crack visualization and image-based numerical simulation has been demonstrated to be powerfuland feasible in revealing and understanding various fracture phe-nomena inside materials.

10:00 AMThermographic Detection of Mechanical DamageP. K. Liaw*, university of Tennessee, USA

In this presentation, a technical talk related to the thermographic de-tection of mechanical damage will be given. A high-speed and high-sensitivity thermographic-infrared (IR) imaging system has beenused for the nondestructive evaluation of specimen-temperature evo-lutions during tensile and fatigue experiments of bulk-metallicglasses (BMGs) and a reactor-pressure-vessel (RPV) steel. The rela-tionship among the temperature, stress-strain state, and mechanicalbehavior is discussed. Both thermodynamics and heat-transfer theo-ries are applied to model and quantify the observed temperature vari-ations during cyclic loading. During fatigue experiments, in-situ ob-servations as well as qualitative and quantitative analyses ofshear-band evolutions and final fracture have been performed bythermography, which can open up wide applications of thermogra-phy in detecting the in-situ heat-related processes, including the me-chanical damage and phase transformation, of materials and struc-tural components.

10:40 AMUsing Simplified Fracture Mechanics Modeling to UnderstandClassical Fractographic Features in Rotating and Three PointBending Fatigue (Invited)D. Aliya*, Aliya Analytical Inc., USA; J. Raphael, JR Technical Services, USA

Many people see the end result of an unfortunate event when theylook at a fracture surface. Reasonably simple geometries however,lend themselves to relatively immediate and more dynamic views ofhow and why the crack initiated and grew the way it did. A simplefracture mechanics model of the stress intensity (KI) at the leadingand trailing edges of a short circumferential (transverse) crack in arotating shaft may shed light on the asymmetrical growth of the cracktip. Likewise, a model comparing the stress intensity in crack opening

(KI) at the tensile surface and in “in-plane” shear (KII) at the neutralaxis of a simple beam may shed light on why step like features some-times form on the fracture surfaces of leaf springs in automotive ap-plications. Examples of fracture surfaces and results of the modelswill be presented.

11:00 AMOverview of Steel Wear Research in Tumbling Mill Grinding(Invited)P. Radziszewski, A. Sabih*, S. Martins, B. Picard, McGill University, Canada

Tumbling mills are systems composed of a set of elements that worktogether to accomplish ore breakage. The essential elements of thesetumbling systems are mill shell, liners and media. The function of themill liners is to protect the mill shell while transferring energy to themill charge. The mill charge is composed of mill media (ball or rods)and rock and/or slurry and its function is to nip and break the orethrough impact or shear. This paper (presentation) is an overview ofthe research results related to understanding better the dynamics ofthe mill charge motion and how it affect steel liner and media wearthrough simulation, instrumentation and experimentation. Specifi-cally, we will present results on liner wear sensor development, in-strumented ball development; charge motion simulation and steelmedia wear prediction.

11:20 AMIgnition of Titanium Clad Steel in Pressure Oxidation LeachingAutoclavesB. E. Hansford*, S. Liu, E. Vidal, Colorado School of Mines, USA; J. Banker,Dynamic Materials Corporation, USA

The mining industry utilizes pressure acid leaching (PAL) and pres-sure oxidation leaching (POX) autoclaves constructed out of tita-nium clad steel for the refinement of certain ore bodies. Previouswork showed in elevated temperature and pressure environments likethose inside POX autoclaves promoted ignition was possible do to theexothermic nature of the oxidation of titanium. This study focusedon the characterization of the damage to POX autoclave caused by apromoted fire on the titanium surface. SEM, XRD, and light mi-croscopy examination identified TiO, α-Ti and TiO dendrites, Fe2Tiintermetallic and TiC phases in the resolidified portion of the tita-nium clad steel flange. The exothermic nature of the formation reac-tions of these phases is believed to help sustain the titanium fire andmelting of the flange. A thermodynamic model was developed to de-termine the amount of heat generated during the formation of thedifferent phases.

Fundamentals & Characterization: Fatigue ofMaterials: Competing Failure Modes andVariability in Fatigue Life

Modeling, Statistics, Life PredictionRoom: 305Session Chairs: C. Boehlert, Michigan State University; S. Jha,Universal Technology Corporation

8:00 AMMicrostructure-Sensitive Modeling of High Cycle Fatigue (Invited)C. Przybyla, R. Prasannavenkatesan, N. Salageheh, D. L. McDowell*, GeorgiaTech, USA

We explore microstructure-sensitive computational methods for pre-dicting variability of low cycle fatigue (LCF) and high cycle fatigue(HCF) processes in metallic polycrystals to support design of fatigueresistant alloys. We outline a philosophy of establishing relations be-tween remote loading conditions and microstructure-scale plastic-ity/crack behavior as a function of stress amplitude, stress state andmicrostructure, featuring calibration of mean experimental re-sponses for known microstructures that bound the range of virtual

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 239

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania240

(digital) microstructures. Effects of process history and resultingresidual stresses are considered in certain cases of subsurface crackformation. The need to characterize extreme value correlations of mi-crostructure attributes coupled to the local driving force (i.e., fea-tures) for HCF crack formation is outlined, along with a strategy in-volving a set of Fatigue Indicator Parameters (FIPs) relevant todifferent mechanisms of crack formation.

8:40 AMOn Stochastic Evaluation of S-N Data Based On Fatigue StrengthDistributionS. Hanaki*, M. Yamashita, H. Uchida, University of Hyogo, Japan; M. Zako,Osaka University, Japan

To design structures or machines, a permissible stress is estimatedfrom an S-N curve with safety factors. Though S-N curves are esti-mated by experimental data, the test results show large scatter. There-fore, S-N curves should be decided by a statistical method. In thisstudy, a decision method of S-N curve based on evaluation of fatiguestrength distribution has been proposed. In the proposed method, alldata sets of fatigue test results were normalized. This procedure com-bines a set of data into one group and makes it possible to estimatethe distribution of fatigue strength using relatively small number ofsamples. The proposed method has been applied to the fatigue testdata for some materials and reasonable S-N curves were obtained.Besides, design criteria for given failure probability can be obtainedeasily because the proposed method evaluates the fatigue strengthdistribution.

9:00 AMObtaining High Cycle Fatigue Data (S-N) From Energy ReleaseRate ConceptH. Saghizadeh*, B. Farahmand, Boeing, USA

S-N data is currently obtainable through the ASTM testing stan-dards, which is costly and time consuming. The proposed techniqueprovides a novel and innovative approach based on the energy re-lease rate concept that will relate the amount of energy releasedfrom an almost uncracked condition to some visible crack. It is as-sumed that structural parts are not totally free from defects. The cal-culated energy release rate will be incorporated into the crackgrowth rate equation to calculate the number of cycles to failure. Re-sults of stress versus number of cycles to failure (S-N) were com-pared with the existing data available in the MIL-HDBK5 for a fewaluminum alloys currently used in space and aircraft parts. Goodagreement between the analysis and test data was obtained and asthe result an Excel program was established which will provide theS-N data for the analyst without conducting costly and timelyASTM tests.

9:20 AMExtreme Value Marked Correlation Statistics in HCF of Ti-6Al-4VC. P. Przybyla*, D. L. McDowell, Georgia Institute of Technology, USA

Variability in fatigue life of duplex Ti-6Al-4V is documented exper-imentally; however, quantitative statistical approaches that link vari-ability in fatigue life to local microstructure stochasticity are lack-ing. The objective of this research is to apply a newly proposedframework that estimates the extreme value probability distribu-tions of existing hot spots where driving forces for fatigue damageformation are high along with the probabilities of existing coupledmicrostructure attributes at these fatigue hot spots to explore fa-tigue variability in Ti-6Al-4V. The driving forces for fatigue damageformation are predicted using crystal plasticity models via FEMsimulations to estimate local distributions of certain fatigue indica-tor parameters. The microstructure attributes considered includegrain orientation, misorientation and short range interactions be-tween grains. Simulated microstructure instantiations are optimized

to be statistically representative of real experimentally characterizedTi-6Al-4V.

10:00 AMCompeting Failure Modes in Aerospace Alloys and theImplications for Life Management Approaches (Invited)M. Caton*, J. Larsen, Air Force Research Lab, USA; S. Jha, UniversalTechnology Corporation, USA

Recent fatigue studies of numerous aerospace alloys have revealedcompeting failure modes under relevant loading conditions con-tributing to dual-fatigue lifetime distributions. It has been observedthat inherent fatigue life variability is often composed of a popula-tion of life-limited specimens that experience immediate crack ini-tiation and a population of long-life specimens that demonstrate asignificant crack initiation period. The life-limited population iswell described by the variability in small and long crack growthrates. Alloys demonstrating this phenomenon include Ni-base su-peralloys, Ti alloys, Al alloys, and γ-TiAl. Recognizing the competi-tion of these distinctly different mechanisms enables reduced un-certainty in life prediction methods and has significantimplications for damage prognosis and life-management practicesfor fracture critical components. The framework for applying prob-abilistic life prediction methods for aerospace structures will bepresented.

10:40 AMComputational Model to Predict the Statistical Nature ofCompeting Fatigue Mechanisms (Invited)R. Tryon*, VEXTEC, USA

This presentation discusses a computational material microstruc-tural model with location specific material properties and compet-ing fatigue mechanisms. The model is used to predict the probabilityof fatigue failure of full scale component exposed to complex load-ing scenarios. Monte Carlo simulation combines the microstructuralgeometry and the local damage mechanism with the macrostruc-tural load from full scale component finite element analysis. Themodel allows for multiple failure mechanisms to occur simultane-ously and their interaction and correlation are determined. Themethodology does not rely on empirical damage initiation curvesbut on the underlying microstructural geometry and crystallo-graphic strains. Damage accumulation is predicted on a cycle bycycle basis. Manufacturing induced residual stress and other initialstate variable are included. The model efficacy is established by com-paring model with test results in aluminum, steel, titanium andnickel components.

11:20 AMBimodal Fatigue Life Behavior: A Formal Analysis Frameworkwith Applications (Invited)C. McClung*, M. Enright, Southwest Research Institute, USA

In some turbine rotor materials, fatigue lifetimes exhibit a bimodaldistribution arising from different formation mechanisms. Studies ofIN100 at AFRL, for example, have shown that different failure popu-lations are associated with subsurface or surface crack formation atnon-metallic particles or pores. In this study, a practical engineeringframework with a formal probabilistic basis is developed to performfatigue life prediction for competing failure mechanisms. Probabilis-tic models that characterize each of the failure mechanisms and asso-ciated fatigue life distributions are implemented within the DARWINcomputer program for design assessment of rotor reliability. The newDARWIN framework is first validated against available laboratorycoupon data from AFRL, and then exercised on DARWIN models ofvirtual components, in order to explore how different failure modesoperate on component geometries with a variety of sizes, shapes, andstress distributions.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 240

Th

urs

day

AM

www.matscitech.org 241

12:00 PMDevelopment of a database for the prediction of fatigue behaviorin Timetal 555J. Foltz*, B. Welk, P. Collins, J. C. Williams, H. L. Fraser, The Ohio StateUniversity, USA

It is known that the mechanical properties of Timetal 555 (Ti-5Al-5V-5Mo-3Cr-0.5Fe) can vary significantly as a result of changes inthermomechanical processing. These changes in properties, due tovariations in the size and distribution of microstructural features re-sulting from the thermal histories, should also affect the fatigue prop-erties of the alloy. Thus, a database is currently under development torelate the microstructural features of the material and the fatigue be-havior. The thermal histories have been precisely controlled usingtwo types of thermomechaical simulators (a Gleeble® and anETMT™), and the resulting fatigue behavior measured and mi-crostructures quantified. Selected samples have been further analyzedusing advanced characterization techniques, including EBSD andTEM. These preliminary fatigue life results will be presented and cor-related with significant microstructural features such as grain bound-ary α, secondary α width, volume percent α and prior β grain size.

Fundamentals & Characterization:International Symposium on Defects,Transport and Related Phenomena

Defects and Transport in Ceramics IVRoom: 307Session Chairs: Han-Ill Yoo, Seoul National University; Klaus-DieterBecker, Technische Universität Braunschweig

8:00 AMDefects Resulting from Thermochemical Interactions at InnerElectrodes (Invited)C. Randall*, A. Polotai, S. Lee, W. Liu, N. Donnelly, G. Yang, E. Dickey, ThePennsylvania State University, USA

In multilayer actuators and multilayer capacitors, the long-term sta-bility of the electrical properties is frequently limited by the migra-tion of ionic species in the grain boundaries or through the bulkgrains, which slowly modifies the electrical conductivity as a functionof time and leads to the breakdown of the dielectric or piezoelectriclayers and a failure of the device and/or system. With thinner layersand/or higher voltage and temperature operation, the kinetics of theprocesses controlling the degradation rates are problematic. We ad-dress here a variety of measurement techniques to help understandthe local phenomena that control the degradation kinetics (imped-ance spectroscopy, thermally stimulated current, and a combinationof electron microscopy techniques that permit quantification of localchanges in structure and stoichiometry). We are able to separate theimpact of different processing routes as well as chemical modifica-tions that can retard processes that lead to degradation.

8:40 AMSpace charge at grain boundary investigation by nano-scale TEMmicroanalysis in spinel MgAl2O4B. Franck*, C. Jacques, N. Nicolas, M. Alexandre, University of Lille1, France

The grain boundary chemistry of fine-grained spinel MgO.nAl2O3(mean grain size below micron) has been investigated by STEM mi-croanalysis. Thanks to the South Bay technology tripod polisher toprepare sample and to the Van Capellen-Doukhan’s method to de-termine foil thickness, we were able to quantify the concentration ofeach element across the grain boundaries. Stoichiometry variationsare observed from the grain boundary region to the bulk. TheAl/Mg ratio increases from 2.1 in the bulk to 2.35 at the grainboundary regions. X-ray quantification allows us to reveal and tocharacterize the space-charge layer in the subgrain boundary. The

grain boundary cores are negatively charged due to VMg” vacanciesin excess and, a positive space-charge layer in the subgrain boundaryregion is obtained. The composition of point defects and the char-acteristics (sign, space-charge potential, Φ) of the space-charge layerare discussed.

9:00 AMHall Effects on Galium and Cupper doped Pr2NiO4 MixedConductor for oxygen permeation (Invited)T. Ishihara*, K. Tominaga, H. Matsumoto, Kyushu University, Japan

High oxygen permeation rate is achieved on Pr2NiO4 doped with Cuand Ga. In this study, temperature dependence of hole in this mixedconductor was investigated by using Hall effects. With increasingtemperature, carrier density as well as mobility increased but at tem-perature higher than 700 K, carrier density decreased in spite of tem-perature increase. This was explained by thermal reduction of Pr4+and Ni3+. On the other hand, by doping gallium, carrier density de-creased and so, gallium works as donor. Since oxygen vacancy was in-troduced by doping gallium, oxygen permeation rate was much im-proved by doping Ga. Effects of oxygen partial pressure on holeconcentration was also studied by Hall effects and mobility of hole isunchanged, but carrier density decreased by decreasing PO2. Detaildefects chemistry in this oxide was also discussed by thermal gravi-metric method.

10:00 AMDiffusion Characteristics in Isotope-Hetero-Structural Thin Filmswith Wurtzite Structure (Invited)H. Haneda*, National Institute for Materials Science, Japan; K. Matsumoto,Kyushu University, Japan; T. Ohgaki, T. Nakagawa, Y. Yao, I. Sakaguchi, N.Ohashi, National Institute for Materials Science, Japan

GaN, AlN thin films were synthesized with a molecular beam epitax-ial method. ZnO films also deposited with a pulse laser depositionmethod. Thin films with a Ga14N/Ga15N/Ga14N,Al14N/Al15N/Al14N and Zn16O/Zn18O/Zn16O isotopic het-erostructures were also grown. A CAMECA-type SIMS was em-ployed to analyze impurities such as substrate elements. Nitrogenand oxygen isotopes were also analyzed. Some samples were an-nealed, and then the diffusivities of the elements and isotopes wereevaluated. Although the crater surface after using Cs+ ions as theprimary ion beam became smoother than after using O2+, preferen-tial sputtering was observed during the analysis of GaN thin films. Itis concluded that this preferential sputtering causes the isotope dis-tribution to be abnormal. Elements of the substrates diffused intothe thin films. We will discuss the anion diffusivity in the wurtzitestructure.

10:40 AMOxidation and hydration kinetics of proton conductor oxides(Invited)H. Yoo*, J. Kim, Seoul National University, South Korea

Oxidation and hydration kinetics was examined on the systems ofSrCe0.95Yb0.05O2.975 and BaCe0.95Yb0.05O2.975 via conductivityrelaxation upon a sudden change of oxygen activity in fixed water ac-tivity atmospheres, and vice versa, at elevated temperatures. It hasbeen found that under an oxygen activity gradient in a fixed watervapor activity atmosphere, the conductivity relaxation is monotonicwith a single relaxation time as usual, yielding one and only onechemical diffusivity that is unequivocally for component oxygen. In awater activity gradient in a fixed oxygen activity atmosphere, on theother hand, the conductivity relaxation appears quite unusual, ex-hibiting an extremum after initial transient. The relaxation upon hy-dration or oxidation, in general, is quantitatively analyzed in terms oftwo apparent chemical diffusivities for component oxygen and hy-drogen, respectively, and the chemical diffusivities are evaluated.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 241

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania242

Fundamentals & Characterization: Lifecycleof Engineered Residual Stresses: Processing,Aging, and Rejuvenation

Lifecycle of Engineered Residual Stresses: Processing,Aging, and RejuvenationRoom: 310Session Chair: Calvin Tszeng, Berkeley Materials Research

8:00 AMEvolution of Microstructure and Residual Stresses Induced bySurface Severe Plastic Deformation in a Multi-Phase Ni SuperalloyT. Shimamura, Nagaoka University of Technology, Japan; L. Shaw*,University of Connecticut, USA

Surface severe plastic deformation (S2PD) processes have been re-cently developed to introduce nano-grains and large residual stressesin the surface region of bulk metallic materials. In this study, we haveexamined how the residual compressive stresses and nanocrystallinesurface layer of a nickel superalloy, IN 718, in the solutionized condi-tion change with the processing conditions of the S2PD process andthe subsequent aging treatment. It is shown that the residual stressdecreases gradually as the aging temperature increases from 500 to718 C. The nano-grains also grow gradually as the aging temperatureincreases. However, the hardness of the processed surface regionshows an increase when the aging temperature is at 500 and 650 C be-fore decreasing with aging at 718 C. The mechanisms responsible forthese phenomena are proposed and confirmed with XRD and SEMexamination.

8:20 AMStudy on Residual Stress Measurement of Aluminum Pipe UsingRaman SpectroscopyM. Kang*, S. Kim, J. Koo, C. Seok, Sungkyunkwan University, South Korea

In most cases, used pipes in various mechanisms and structures areproduced by extruding and drawing. Also, the pipe is used after it hasbeen bent in a complex manner and cut to fit it to those. In thisprocess, its plastic deformation produces the residual stress. Thisresidual stress significantly affects the fracture behavior of the pipe.Measuring the residual stress of a U-shaped aluminum pipe is diffi-cult with existing destructive and nondestructive measurementmethods. Because raman spectroscopy provides details on the chemi-cal composition, molecular structure, and molecular interactions incells and tissues, raman spectroscopy is a good tool for evaluating theresidual stress. In this paper, the residual stress of a U-shaped alu-minum pipe was evaluated from the Raman shift. First the residualstress was evaluated by raman spectroscopy. And these results ofRaman spectra were compared with FEM analysis for the residualstress distributions in the U-shaped aluminum pipes.

8:40 AMMicrostructure and Residual Stress Distributions in Laser ShockPeening Processed Ti-6Al-4V AlloyY. Zhao*, S. R. Mannava, V. K. Vasudevan, University of Cincinnati, USA; J.Almer, U. Lienert, Y. Ren, Argonne National Laboratory, USA; D. Lahrman,LSP Technologies, USA

Laser shock peening is a surface process that generates deep compres-sive residual stresses and microstructural changes and dramaticallyimproves fatigue strength of critical metal aircraft engine parts. Thepresent study was undertaken to develop a basic understanding of theeffects of LSP parameters on the residual stress distributions and mi-crostructural changes in Ti-6Al-4V. Coupons of the alloy with andwithout a ablative layer were LSP-treated using the LSP system at GEand LSP Technologies,Inc. Depth-resolved characterization of themacro residual strains and stresses and was achieved using high-en-ergy synchrotron x-ray diffraction. The near-surface and through-

the-depth changes in strain, texture and microstructure were studiedusing EBSD/OIM and by TEM of thin foils fabricated from specificlocations using the FIB method. The results showing the relationshipbetween LSP processing parameters, microstructure, residual stressdistributions and hardness are discussed.

9:00 AMEffects of Cold Working, Shot Peening and Post Annealing onResidual Stress and Microstructure of Ni-Base Alloys IN718 andWaspaloyH. Song*, P. B. Nagy, V. K. Vasudevan, University of Cincinnati, USA

The present work combines measurements of electricalresistivity/conductivity with detailed characterization of microstruc-ture and quantitative analysis in a study of cold-worked and shot-peened IN718 and Waspaloy. The aim was to achieve a better funda-mental understanding of the changes in microstructure induced bymechanical treatments of nickel-base superalloys and relate these toproperty changes, in order to better establish the relationship be-tween the nondestructively measured frequency-dependent apparenteddy current conductivity signature and the sought subsurface resid-ual stress profile in surface-treated nickel-base superalloys. Coldworking leads to a substantial hardening and an increase or smallerchanges in conductivity. Shot peening led to near-surface compres-sive residual stresses and an increase in hardness. Post-annealing ledto partial or total relaxation of the residual stresses and either a loss orgain in hardness.

9:20 AMEffects of Laser Shock Peening on Residual Stress Distributionsand Microstructure of IN718 SuperalloyA. Gill*, University of cincinnati, USA; J. Almer, U. Lienert, Y. Ren, APS,Argonne National Laboratory, USA; D. Lahrman, LSP Technologies, USA; V.Vasudevan, S. Mannava, University of cincinnati, USA

LSP dramatically improves fatigue strength, life and crack propaga-tion resistance and hence service lifetimes of critical metal parts likeaircraft engine fans and compressor blades by shock wave-inducedcompressive residual stress and microstructural changes. The studyaims to understand effects of LSP parameters on residual stress distri-butions and microstructural changes in important aero-engine mate-rial, IN718. Coupons of alloy with and without sacrificial layer wereLSP-treated with varying energy densities. Depth-resolved character-ization of macro residual strains/stresses was achieved using high-en-ergy synchrotron XRD and conventional XRD. Near surface andthrough depth changes in strain, texture and microstructure werealso studied using EBSD in SEM and TEM. Studies were also done ofthermal stability of residual stresses and microstructure. The resultsshow relationship between LSP parameters and residual stress distri-butions, microstructure and thermal stability

10:00 AMAnalysis of Fatigue Test Results of U-shaped Copper Pipe byConsidering Residual StressS. Kim*, J. Koo, C. Seok, Sungkyunkwan Univ., South Korea

In mechanical structures of power sources, such as pipes, repeatedforce occurred by motors and pipes reduces its life and ultimately col-lapses. Such pipes consist of several shapes and among them, U-shapepipe is specially damaged well. In most cases, U-shape pipe is madefrom a straight pipe by complicated bending work. During this workprocess, its plastic deformation produces residual stress in the pipe.This residual stress significantly affects the fracture behavior of pipeand brings on a change of stress ratio(min. stress/Max. stress = R). Inthis paper, the residual stresses of U-shaped pipe were evaluated byFEM analysis. And, the fatigue tests of U-shaped pipe are performedby uniaxial fatigue testing machine. So, its fatigue test results aremodified with the results of FEM (Finite Element Method) analysis

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 242

Th

urs

day

AM

www.matscitech.org 243

for residual stress. The modified fatigue test results of U-shaped pipewere compared with those of straight pipe.

10:20 AMA thermo-mechanical model to predict the tribological behaviorof Ti6Al4V/carbide pair for dry sliding conditions and itsapplication to predict residual stresses in machining processesB. M. Abraham*, S. Y. Liang, Georgia Institute of Technology, USA

Due to the increasing drive for productivity improvements and con-sistent part dimensionality,especially in aerospace structures,therehas always been a challenge to understand underlying mechanisms ofresidual stresses. A sensitivity analysis of parameters such as thespeed,tool edge radius,coefficient of friction(COF) etc reveals thatthe COF is the most dominant factor affecting residual stress.Theoverall goal of the paper is to identify a relationship that correlates thenormal pressure,velocity of sliding and temperature in contact withthe COF using multiple linear regressions for Ti6Al4V/carbidepair.By utilizing the friction model,residual stresses are predicted fora machining process.It was found that the velocity of sliding affectedthe COF the most and that the friction has a profound effect on theresidual stress on the machined surface but not in-depth into theworkpiece.

10:40 AMStability of Residual Stresses in Shot-Peened Ti-6Al-2Sn-4Zr-6MoR. John*, US Air Force Research Laboratory, USA; D. Buchanan, University ofDayton Research Institute, USA; S. Jha, Universal Technology Corporation,USA; J. Larsen, US Air Force Research Laboratory, USA

The benefits of shot-peen induced compressive residual stresses inimproving fatigue life and retardation of crack growth have been ex-tensively demonstrated. Therefore, beneficial surface treatments suchas shot peen, laser shock peen and low plasticity burnishing are tar-geted for many applications in aerospace components. During thecomponent service, the shot-peen residual stresses may change dur-ing cyclic loading, or during elevated temperature static loading, suchas thermal exposure and creep. Hence, life prediction of these compo-nents requires understanding of the stability of the residual stressesunder service loading conditions. This presentation describes thecharacterization of shot-peen residual stress relaxation in alpha+betaprocessed Ti-6Al-2Sn-4Zr-6Mo. Shot-peened specimens were sub-jected to thermal-mechanical loading conditions ranging from roomtemperature to 399C (750F). Results of the residual stress relaxationexperiments and the implications on life extension will be discussed.

11:00 AMThermal Relaxation of Shot Peened and Laser Shock PeenedResidual Stresses in a Nickel-Base SuperalloyD. Buchanan*, University of Dayton RI, USA; R. John, M. Shepard, Materials& Manufacturing Directorate, AFRL/RXLMN, US Air Force ResearchLaboratory, USA

Shot peening (SP) is a commonly used surface treatment that impartscompressive residual stresses into the surface of components. Theshallow depth of compressive residual stresses, and the extensive plas-tic deformation associated with shot peening, has been overcome bymodern approaches such as laser shock peening (LSP). LSP surfacetreatment produces compressive residual stress magnitudes that aresimilar to SP, that extend 4-5 times deeper, and with less plastic defor-mation. Retention of compressive surface residual stresses is neces-sary to retard initiation and growth of fatigue cracks under elevatedtemperature loading conditions. This presentation compares thethermal relaxation behavior of SP and LSP residual stress profiles in apowder metal nickel-base superalloy (IN100) for a range of tempera-tures and exposure times. Results indicate that the LSP processing re-tains a higher percentage of the initial (as processed) residual stressprofile over that of SP.

11:20 AMEvaluation of Residual Stress Relaxation and MicrostructuralChanges in Laser Shock Peened Ni-Base Alloy IN718 PlusV. Chaswal*, University of Cincinnati, USA; D. Lahrman, LSP Technologies,USA; Y. Ren, Argonne National Lab, USA; D. Qian, S. R. Mannava, V. K.Vasudevan, University of Cincinnati, USA

Laser shock peening (LSP) improves fatigue life by introducing deepsubsurface residual stresses. Since residual stresses are prone to ther-mal relaxation, we study their thermal stability upon aging at servicetemperatures in a laser shock peened IN718 Plus high temperaturealloy. Conventional and high-energy synchrotron X-ray radiation(SXRD) is used to characterize the near-surface and through thick-ness residual stresses. Residual stresses are compared between: (1) un-peened and (2) double side laser peened IN718P peened condition,and after thermal aging at 700°C for times of (3) 1h and (4) 10h. Roleof thickness is studied using 1mm and 5mm thick samples. Mi-crostructures of the LSP samples, and the structure, size, and distri-bution of second phases were evaluated by scanning (SEM) andtransmission electron microscopy (TEM). Local changes in mi-crostructure were established as a function of thermal aging, and ra-tionalized with S-XRD, XRD and hardness results.

Fundamentals & Characterization:Performance and Growth of Bulk and ThinFilm Materials - Role of Surface and InterfacePhenomena during Growth and Processing

Microstructures and Properties of Thin Films in theSub-Micron Range and BeyondRoom: 306Session Chair: Roger Narayan, University of North Carolina

8:00 AMEffect of Oxygen Gas on the Deposition of Reactively SputteredCarbon Thin Films (Invited)T. McKindra*, M. J. O’Keefe, Missouri University of Science andTechnology, USA

The effect of using O2 with Ar during reactive sputter deposition ofcarbon thin films was investigated. Carbon films were deposited ontoSi substrates (1x1 cm) by DC magnetron sputtering of a graphite tar-get using Ar only, then 5, 10, and 25% O2 gas at working pressures of2 and 5 mTorr. The films were deposited at 300 W and the thicknessmeasured with a profilometer. The deposition rate decreased with in-creased partial pressure of oxygen in the process gas. Films that ap-peared optically different from the others were selected for furthercharacterization by x-ray diffraction (XRD), x-ray photoelectronspectroscopy (XPS), electron spectroscopy and Raman spectroscopy.The XRD results revealed the films to be generally amorphous withsome broad peaks. The broad peaks were only detected with the addi-tion of oxygen to the process gas. The XPS spectra for the selectedsamples exhibited shoulders at a higher binding energy associatedwith C-O bonding.

8:40 AMEffects of Oxygen and Hydrogen on Surface Morphology of MgOFilms Deposited by Ion-PlatingH. Kim*, S. Ryu, J. h. KIm, Korea Institute of Ceramic Engineering &Technology, South Korea; J. J. Kim, Samsung SDI, South Korea

The effects of oxygen and hydrogen on surface morphology ofMgO film, which is protective layer of plasma display panel(PDP),were investigated by ion plating coating process. The surface mor-phology and crystalline planes were influenced not by oxygen con-tent but by hydrogen content; the shape and size of grains werechanged from the small triangle (50nm), bigger triangle

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 243

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania244

(100~200nm), lozenge (100nm), and then to very small round(under 20nm) shape along with hydrogen amount. The preferredorientations of MgO films were (111) and (222) without hydrogen.However, (111) and (222) peaks decreased and (200) planes ap-peared according to hydrogen amount. The crystallinity of MgOfilm was hardly recognized in case of excess hydrogen introduction,over 90sccm.

9:00 AMLattice behavior of carbon doped HPCVD MgB2 thin films fromfirst-principlesA. Saengdeejing*, Y. Wang, Z. Liu, Pennsylvania State University, USA

With increasing carbon content, the lattice parameters of bulk MgB2show different trends when compared with those of thin films pro-duced by Hybrid Physical-Chemical Vapor Deposition (HPCVD). Tounderstand these phenomena, first-principles calculations are per-formed on MgB2 superconductor, carbon doped MgB2 and MgB2C2.Aided by the CALPHAD approach, we predict the existence ofMgB2C2 second phase in the MgB2-C pseudobinary system. A modelexplaining the lattice behavior of the carbon doped MgB2 thin films isthen proposed based on the first-principles predicted thermal expan-sion coefficients and elastic constants. We find that the different de-pendences of lattice parameters on the carbon content between thinfilm MgB2 and bulk MgB2 are due to the differences in the coefficientsof thermal expansion and elastic constants of MgB2 and MgB2C2which is present as a second phase in the HPCVD thin films. The ef-fect of graphite at high carbon concentrations is also discussed.

9:20 AMCs-corrected STEM Characterization of CaxCoO2 FilmR. Huang*, Japan Fine Ceramics Center, Japan; K. Sugiura, NagoyaUniversity, Japan; T. Mizoguchi, the University of Tokyo, Japan; H. Ohta, K.Koumoto, Nagoya University, Japan; Y. Ikuhara, T. Hirayama, Japan FineCeramics Center, Japan

Layered cobalt oxides, including γ-NaxCoO2 and CaxCoO2 etc., haveattracted much attention due to their good thermoelectric perform-ance. In the present study, the Ca ordering of CaxCoO2 films are in-vestigated by using Cs-corrected scanning transmission electron mi-croscopy (STEM). Ca0.32CoO2 thin films with √3a × √3a hexagonaland 2a × √3a orthorhombic ordered structures were made by reactivesolid-phase epitaxy (R-SPE) method and following ion-exchangetreatment. The Ca0.32CoO2 film on sapphire m plane mainly formed√3a × √3a ordered structure. However, some regions close to the sur-face show 2a × √3a ordered structure, which can be easily distin-guished from √3a × √3a ordered structure by the inbetween contrastof Ca pairs. Ca0.32CoO2 film on c plane forms 2a × √3a ordered struc-ture after annealing at 400oC. Residual Co3O4, Ca-Al-O amorphous,and CoO seed layer were observed in all samples.

10:00 AMAnalysis of NiAl-Hf Bond Coats via Tomographic Atom Probe andTransmission Electron MicroscopyM. A. Bestor*, M. S. Kirsch, R. L. Martens, M. L. Weaver, The University ofAlabama, USA

The microstructures of NiAl-Hf bond coats have been investigatedvia tomographic atom probe (ATP) and transmission electron mi-croscopy (TEM). Nanometer-sized Hf-rich precipitates formed inNiAl-1.0 at.% Hf coatings following post-deposition annealing at1000°C. This resulted in smaller mass gains during isothermal oxida-tion with values approaching those of model NiAl-0.05 at.% Hf coat-ing alloys. TEM revealed a nearly homogeneous distribution of pre-cipitates (within grain interiors and on grain boundaries) with largerprecipitates forming at the grain boundaries. ATP results show thatlarge amounts of carbon within the precipitates and at grain bound-aries. The carbon appears to segregate locally with the Hf. Results will

be discussed relative to phase equilibria and oxidation of bulk NiAl-Hf alloys.

10:20 AMBandgap reduction and photoelectrochemical properties ofZnO:N films deposited by reactive RF magnetron sputteringS. Shet*, K. Ahn, T. Deutsch, Y. Yan, J. Turner, M. Al-Jassim, NationalRenewable Energy Laboratory, USA; N. M. Ravindra, New Jersey Institute ofTechnology, USA

ZnO:N films were deposited by reactive RF magnetron sputteringin mixed N2 and O2 gas ambient. Their PEC properties weremeasured and compared with those of as-grown and annealedZnO films. The ZnO:N films exhibit photoresponse in the visible-light region, yielding higher total currents than pure ZnO thinfilms. With combined UV/IR and color filtering, our data indicatethat the main contribution to the high photocurrent is from theabsorption of light in long-wavelength regions. Our resultsdemonstrate that N incorporation in ZnO can narrow the bandgapand create absorption in the visible-light region for ZnO films,suggesting that N-incorporation could be a potential method toimprove the efficiency of PEC water splitting utilizing ZnO-basedmaterials.

10:40 AMSuperplastic Boronizing of Duplex Stainless Steel (DSS): InitialPressure and Surface Roughness EffectH. Mohd Yusof*, I. Jauhari, N. Abd Aziz, University of Malaya, Malaysia

In this work, a further study on boronizing using compressionmethod called superplastic boronizing (SPB) was conducted. Thisprocess was conducted on duplex stainless steel (DSS) which hasbeen thermo-mechanically treated to obtain fine grain mi-crostructure and exhibit superplasticity. Effort was being put inobtaining hard surface through SPB by focusing on the surfaceroughness and initial pressure effects. SPB was conducted at 1223K, for 4 hours under three different surface roughness, Ra (0.9μm, 0.1 μm, and 0.03 μm) and initial pressure (25 MPa, 49 MPa,and 74 MPa) conditions. Boronized layer thickness in the range of35.3 μm to 91.9 μm and surface hardness in the range of 1558 HVto 2602 HV were obtained. Boronized layer thickness and hard-ness increased with the decreasing of surface roughness and in-creasing of initial pressure. The effects of surface roughness on theSPB were seen to be more significant than the effects of initialpressure.

11:00 AMProtective Aluminum Oxide-based Coatings against MetalDustingD. V. Melo-Maximo*, Instituto Politecnico Nacional, Mexico; J. Alvarez, O.Salas, J. Oseguera, Instituto Tecnologico de Estudios Superiores (CampusEstado de Mexico), Mexico; V. M. Lopez-Hirata, Instituto PolitecnicoNacional, Mexico

Some steels are subjected to metal dusting corrosion in highly car-burizing atmospheres, which represents significant economicallosses in some industrial processes. An approach to metal dustingprevention is based on the formation of a dense layer of oxide on thesteel surface. In the present work, PVD coatings of protective alu-minum oxides have been applied to HK40 substrates. The coatingswere produced by reactive magnetron sputtering under differentprocessing conditions. Thermogravimetric analysis of the coatedsamples was then carried out in metal dusting conditions. The mi-crostructure of the samples after coating and after metal dusting wasanalyzed by scanning electron microscopy + energy dispersive analy-sis and x-ray diffraction. The results indicate that the density and ad-herence of the coatings is central for effective protection againstmetal dusting.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 244

Th

urs

day

AM

www.matscitech.org 245

Fundamentals & Characterization: PhaseStability, Diffusion Kinetics and TheirApplications (PSDK-III)

Microstructural Analysis, Control and Modeling IIIRoom: 302Session Chair: Yongho Sohn, University of Central Florida

8:00 AMPragmatic Phase-Field Approach for Modeling Diffusion- andCurvature-Controlled Phase Transformations in Technical Alloys(Invited)B. Böttger*, M. Apel, J. Eiken, P. Schaffnit, I. Steinbach, access, Germany

Phase-field modeling is getting more and more popular today. Whilemuch work on this field is still mainly driven by scientific interest,there is also an increasing demand for microstructure simulation intechnical processes and alloys. In this paper we present a “pragmatic”multiphase-field approach which is dedicated primarily to the simu-lation of diffusion- and curvature-controlled microstructure forma-tion in multiphase and multicomponent technical alloys. Herewith,one of the key issues is the direct coupling of the phase-field code tothermodynamic and kinetic databases which are based on Gibbs en-ergy or mobility data and which allow a quite exact description ofeven complex alloy systems with many components and phases. Ex-amples from different material classes are shown. Furthermore, theeffective linking of the phase-field model to complex boundary con-ditions typical for technical processes is demonstrated.

8:40 AMThermal Aging Effects on Microstructural Evolution in IN718Plus AlloyV. Chaswal*, S. R. Mannava, V. Vasudevan, University of Cincinnati, USA

IN718 Plus is the latest high temperature candidate material for aeroengine components with improved peak temperature strength andtoughness over IN718. Its lower Nb and Fe, and higher Al contents areexpected to enhance the γ′ precipitation. Since precipitation harden-ing controlled by γ′, γ″ and δ precipitates in this alloy is strongly de-pendent upon aging time and temperature, microstructural evolu-tion upon thermal aging needs to be re-examined. Hence, thermalaging studies between 650°C to 950°C have been conducted onIN718 Plus alloy originally quenched from 950°C, and comparedwith recent reports on IN718 alloy. The microstructures including thestructure, size, and evolution of second phases were evaluated by X-Ray diffraction (XRD), scanning (SEM), and transmission electronmicroscopy (TEM). The temperature-time dependence of the occur-rence of the γ′, γ″ and δ phases were studied and correlated with cor-responding hardness measurements.

9:00 AMCarburization-Induced Ferrite to Austenite Transformation inStainless SteelsG. M. Michal*, X. Gu, F. Ernst, A. H. Heuer, H. Kahn, Case Western ReserveUniversity, USA

Carburization treatments performed at low temperatures can kineti-cally suppress the diffusion of substitutional alloying elements pro-ducing a condition of paraequilibrium without carbides. Carbonconcentrations can be created that are 1,000 times the equilibriumsolubility at the processing temperature. Achieving high carbon con-centrations in ferrite can provide a driving force for its transforma-tion to austenite even at relatively low temperatures. Carburizationsconducted at 470 C with a 301 stainless steel containing 40 vol. pct.ferrite have produced surface layers that are fully austenitic. Com-pound-energy-based solution thermodynamic modeling of the sta-bility of ferrite and austenite as a function of their carbon concentra-tions under the conditions of paraequilibrium and no carbides has

been used to rationalize the observed transformational behavior. Thecapacity of fully ferritic stainless steels to transform to austenite dur-ing low temperature carburization will be discussed.

9:20 AMElastic properties of dilute Mg alloys from first-principlescalculationsS. Ganeshan*, S. Shang, Z. Liu, PSU, USA

The elastic constants of dilute Mg-X (X= Al, Ca, Li, Y, and Zn) alloyshave been predicted from first-principles generalized gradient approx-imation using the efficient stress strain method, wherein 36-atom su-percell with one impurity is adopted. The effect of impurities on thelattice parameters and local relations of Mg alloys, together with theirelastic, plastic and thermodynamic properties has been investigated.The calculated results are compared with the available experimentalmeasurements. Commendable agreement between the two is obtained

10:00 AMCore-Shell Al3Sc/Al3Li Nanoscale Precipitates in AluminumM. E. Krug, D. Dunand*, D. N. Seidman, Northwestern University, USA

An Al–11.3 at.%Li–0.11 at.%Sc alloy was double-aged to induce firstα′-Al3Sc and then δ′-Al3Li precipitates. Atom-probe tomography re-vealed both single-phase δ′-precipitates and core-shell α′/δ′-precipi-tates (with respective average radii of 16 and 27 nm, and respectivevolume fractions of 12 and 9%). These precipitates confer a highstrength to the alloy. While the δ′-shells contain little Sc (~0.027at.%), the α′-precipitate cores have a high Li content, with an averagecomposition of Al0.72(Sc0.17Li0.11). The Li concentrations in the δ′-phase and the Li interfacial excess at the δ′/α′-interface exhibit signif-icant precipitate-to-precipitate variations.

10:20 AMCoarsening Kinetics of γγ’ Precipitates in the Commercial Nickelbase Superalloy Rene88DTG. B. Viswanathan*, R. Srinivasan, The Ohio State University, USA; J. Tiely,Air Force Research Laboratory, USA; R. Banerjee, University of North Texas,USA; H. L. Fraser, The Ohio State University, USA

The coarsening of coherent ordered γ’precipitates in the disordered γ ma-trix in Ni base superalloys has been described to adhere to the LSW the-ory, governed by the volume diffusion of Al in the Ni(Al) matrix givingrise to cube dependence of γ’ particle size to the aging time. Experimentalresults in this study for Rene88DT, a low misfit superalloy, show good ex-perimental fit for both r3 vs. t and r2 vs. t coarsening models, where r is theparticle radius and t is the aging time. Advanced characterization tech-niques, such as EFTEM, 3DAP Tomography and HRSTEM were used toobtain the modal parameters, such as the size of γ’ precipitates, soluteconcentrations in the ppt and matrix, and structural transition across theγ/γ’ interface. Rate constants derived from the experimental results werecompared with theoretical values considering two different models–vol-ume diffusion suggested by LSW model and trans-interface diffusioncontrolled (TIDC) model proposed by Ardell and Ozolins.

10:40 AMCoarsening in Equiaxially-Solidified Al-Cu Solid-Liquid MixturesJ. L. Fife*, L. K. Aagesen, P. W. Voorhees, Northwestern University, USA

We examine the morphological evolution of solid-liquid mixtures inthe Al-Cu system during isothermal coarsening and with increasingsolid volume fraction. Using both a serial-sectioning technique andx-ray tomography, data is collected for the three-dimensional analysisof these complex structures. The morphology and topology of themicrostructure are analyzed through interface shape distributions(ISDs) and interface normal distributions, which determine theprobability of finding a patch of interface with a given set of principalcurvatures and an interfacial normal oriented in a certain direction,respectively. We find that the microstructure evolves into a highly in-terconnected structure, contrary to conclusions made solely from

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 245

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania246

two-dimensional micrographs. We also find a steady state ISD isreached after a certain coarsening time that varies with the solid vol-ume fraction. We use the experimental microstructure as initial con-ditions in a phase-field model in order to validate these results.

11:00 AMProbing the Early Stages of Elemental Partitioning During theNucleation and Growth of Alpha in the Beta Matrix ofTitanium AlloysS. Nag*, R. Banerjee, University of North Texas, USA; S. Rajagopalan, OhioState University, USA; J. Hwang, University of North Texas, USA; H. Fraser,Ohio State University, USA

The solid-state precipitation of alpha within the beta matrix of tita-nium alloys is a rather complex phenomenon involving both a struc-tural bcc to hcp transformation as well as the appropriate diffusionalpartitioning of the alloying elements. Developments in advancedcharacterization techniques such as high-resolution scanning trans-mission electron microscopy and 3D atom probe tomography allowfor unprecedented insights into the true atomic scale structure andchemistry changes associated with the precipitation of alpha. Such acoupling of 3DAP and TEM observations, on complex beta titaniumalloys, indicate that the structural component of the beta to alphatransformation precedes the diffusional partitioning of the alloyingelements. These results suggest that this is a mixed mode (displacive +diffusive) transformation, similar to the bainite transformation insteels, and will form the basis of this presentation.

Fundamentals & Characterization: RecentAdvances in Structural Characterization ofMaterials

Electron Microscopy and Electron Diffraction:Developments and Applications IIRoom: 309Session Chairs: Amanda Petford-Long, Argonne NationalLaboratory; Geoffrey Campbell, Lawrence Livermore National Lab

8:00 AMIn-Situ Tensile-Creep Characterization of Structural Alloys Usinga Scanning Electron MicroscopeC. J. Boehlert*, S. Longanbach, Michigan State University, USA; M. Nowell, S.Wright, EDAX-TSL, Inc., USA

A technique has been developed to acquire SE and BSE images andEBSD orientation maps during tensile-creep deformation at temper-atures as high as 760C. The EBSD observations during deformationproved to be useful for quantifying the types of grain boundarieswhich have preferentially cracked. Details and limitations of this test-ing technique and the results obtained on structural alloys will bepresented. For boron-modified Ti-6Al-4V(wt.%), the evolution ofcracking in surface TiB whiskers and at alpha/beta interfaces wascharacterized. For titanium-aluminum-niobium alloys, grain bound-ary sliding has been characterized and quantified from local grainboundary measurements. For a cobalt-based superalloy, Udimet 188,grain boundary cracking has been shown to preferentially occur ongeneral high-angle grain boundaries rather than low-angle bound-aries or special boundaries. This result has significant implicationswith respect to grain boundary engineering of structural alloys.

8:20 AMQuantitative Mapping of Cation Content in (Pb,La)(Zr,Ti)O3C. M. Parish*, G. L. Brennecka, B. A. Tuttle, L. N. Brewer, Sandia NationalLaboratories, USA

PLZT [(Pb,La)(Zr,Ti)O3] is a family of perovskite-phase ferroelectricmaterials used for applications such as thin-film capacitors and piezo-electric MEMS devices. Chemical heterogeneity and non-stoichiome-

try related to cation segregation and/or volatility during high temper-ature (~700°C) processing can degrade electrical properties. Using~200 nm thick films of PLZT, we have developed a technique to quan-tify X-ray spectrum images taken in scanning transmission electronmicroscopy (STEM), which allows quantitative examination of cationcontents at a spatial resolution of ~10nm. Results confirm significantPb-volatilization during crystallization, yielding non-ferroelectricfluorite phase on the film surface. Zr and Ti are seen to segregate dur-ing crystallization, resulting in Zr-poor material at the substrate andZr-rich material at the film surface. Annealing in the presence of PbOresults in Pb-replenishment and restored perovskite phase and prop-erties, but does not significantly affect B-site heterogeneity.

8:40 AMUltra High Resolution Backscatter Imaging at Low ExcitationVoltagesC. Hayzelden*, J. R. Porter, D. R. Mumm, University of Calfornia at Irvine, USA

The Zeiss proprietary Energy Selective Backscatter (EsB) Detector™provides the capability of restricting image forming backscatteredelectrons to a preselected energy window. Low voltage back-scatterimaging minimizes the interaction volume of the beam with the sam-ple and enhances image resolution. In addition, precluding electronsthat have lost more than a small amount of their incident energy en-sures that all the image forming electrons will have emanated fromthe sample surface from a location close to the incident beam posi-tion, minimizing any image-degrading background signal due tomultiply scattered electrons. Careful selection of imaging parametersenables optimization of the high resolution image. This enhancedresolution backscatter imaging technique will be demonstrated withimages from a program studying ceramic fuel cell electrode / elec-trolyte boundaries.

9:00 AMHRSTEM imaging and analysis of Bi segregation at GrainBoundaries in a Cu-Bi alloyG. Viswanathan*, S. Rajagopalan, The Ohio State University, USA; F. Otto,G. Eggeler, Ruhr University, Germany; H. L. Fraser, The Ohio StateUniversity, USA

Bi segregation to grain boundaries has been known to cause severeembrittlement in Cu(Bi) alloys through inter-granular fracture. Theamount of Bi segregation has been speculated to be dependent on themisorientaion between neighboring grains. In this study, attemptshave been made to characterize and quantify the Bi segregation tograin boundaries of various misorientations in a polycrystalline Cu-0.0085 wt % alloy through advanced techniques: High resolutionScanning Transmission Electron Microscopy (STEM) imaging ofgrain boundary structure was performed using a probe corrected FEITitan 80-300 STEM operated at 300 kV. Semi-quantitative composi-tional analysis of the grain boundary region with enhanced spatialresolution was performed by energy dispersive spectroscopy (EDS)while electron energy loss spectroscopy (EELS) was used to study thenature of the electronic structure near the grain boundary. The re-sults from these experiments will be presented and discussed in detail.

9:20 AMDirect Atomic Scale Observation of the Structure and Chemistryof Order/Disorder InterfacesS. Rajagopalan*, Ohio State University, USA; R. Banerjee, J. Hwang,University of North Texas, USA; G. B. Viswanathan, Ohio State University,USA; J. Tiley, Air Force Research Laboratory, USA; H. L. Fraser, Ohio StateUniversity, USA

In high temperature materials, such as nickel base superalloys, the in-terface between the ordered gamma prime precipitate and the disor-dered gamma matrix interface plays a critical role in determining thehigh temperature microstructural stability and strengthening mecha-nisms involved. Combining aberration-corrected high resolutionscanning transmission electron microscopy (HRSTEM) with three-

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 246

Th

urs

day

AM

www.matscitech.org 247

dimensional atom probe (3DAP) tomography the atomic scale struc-ture and chemistry across the order/disorder interface in nickel basesuperalloys has been determined. While, the order/disorder interfaceis ~ 4 atomic layers thick, the width of the compositional gradientacross the same interface is ~ 10 atomic layers thick. Such atomic res-olution pictures of these interfaces raises fundamental questions re-garding their definition and is essential for understanding both theirhigh temperature stability as well as their role in strengthening by ob-structing dislocation motion.

10:00 AMThree-Dimensional Atom Probe Tomography of NanocompositeDiamond-like Carbon FilmsT. W. Scharf*, M. C. Romanes, K. Mahdak, J. Y. Hwang, R. Banerjee, TheUniversity of North Texas, USA; R. D. Evans, G. L. Doll, The TimkenCompany, USA

Three-dimensional atom probe tomography (3DAP) studies havebeen carried out for the first time on hydrogenated diamond-like car-bon (DLC) films. Nanocomposite tungsten carbide (predominatelycubic β-WC1-x phase) in mixed amorphous DLC sp3/sp2 C-H matri-ces were characterized using the combination of HAADF STEM im-aging and local electrode atom probe (LEAP) techniques. Alternating,~25 nm thick carbon-rich and tungsten-rich DLC layers were ob-served by HAADF STEM imaging while HRTEM in the tungsten-richlayers revealed well dispersed, nanocrystalline WC (~3 nm) precipi-tates throughout the amorphous C-H matrix. Excellent correspon-dence in the chemical layering was observed with 3DAP which alsorevealed atomic scale structure containing carbon and hydrocarbon-rich fragments (C3

2+ and C2H4+) and tungsten and elemental carbon

fragments (W2+, WC2+, C+ and C2+) in the carbon-rich and tungsten-rich layers, respectively. The morphology of the WC nanoprecipitatesin 3D is also discussed.

10:20 AMMicrostructural Evolution in Near-Alpha Titanium FrictionStir WeldsK. E. Knipling*, R. Fonda, Naval Research Laboratory, USA

Stop-action friction stir welds in Ti-5111, a near-alpha titanium alloy,were analyzed to determine the microstructural evolution that occursahead of the tool during the friction stir welding process. This studydetermined how the base plate material ahead of the tool evolves inresponse to the thermal and deformation fields surrounding the ro-tating tool to generate the fine-grained material that is then sweptaround the tool and deposited in its wake. Specifically, we will revealthe effects of the rotating tool on the grain evolution, phase transfor-mations, and crystallographic texture ahead of the tool, and how theyare related to the corresponding characteristics in the deposited weld.

10:40 AMCharacterization of Metallurgical Effects in Laser Drilling of Ni-based SuperalloysJ. K. Garofano*, H. L. Marcus, M. Aindow, University of Connecticut, USA

Percussion laser drilling is a well-established technique for drillingcooling holes in gas turbine engine components. Laser machining can,however, lead to a range of complex metallurgical effects particularlyin the recast layer and heat-affected zone (HAZ) that may surround thedrilled hole. It is important to understand these effects since the recastand HAZ could have a deleterious effect upon the mechanical proper-ties of laser-drilled components. We have used electron microscopytechniques to study such metallurgical effects in laser-drilled Ni-basedsuperalloys as part of a major program on percussion laser drilling ofcooling holes. In this paper we report a microstructural study on laser-drilled powder-metallurgy (P/M) Inconel 100 (IN100), which was se-lected for this study because it has a very homogeneous microstructureconsisting of fcc γ grains with a hierarchical range of L12 γ′ phase. Assuch, this system provides an extremely sensitive test of HAZ effects.

11:00 AMStructure and Plasmon Resonance Properties of Gold Nanostars asDetermined by Analytical Electron MicroscopyR. Tiruvalam*, P. Clasen, Lehigh University, USA; M. Watanabe, LawrenceBerkeley National Laboratory, USA; M. P. Harmer, C. J. Kiely, LehighUniversity, USA

Colloidal gold has been a topic of great interest recently due to its size-dependent optical, electronic, thermal and catalytic properties on thenanoscale. Understanding the surface plasmon resonances of Aunanoparticles with various morphologies is vital for future chemical &bio-sensing, and nanoscale optical wave-guide technologies. We haveprepared interesting 5-fold Au nanostars, as well as more conventionaldecahedral, icosahedral and cub-octahedral particles, by the reductionof HAuCl4 using oleylamine. The twin boundaries in our nanostars runalong the entire length of the arm, contrary to other reports where theyrun from the particle center to the intersection point of two arms. Thisimplies that fast growth in our case does not occur along the low energycrystalline planes as would be expected. Monochromated EELS studiesof the plasmon resonance modes of the nanostar structures will be pre-sented and compared to those of spherical Au particles and nanorods.

11:20 AMSTEM-EELS Analysis of Pressureless Sintered W(Ta)CB. P. Gorman*, Univ. of North Texas, USA; M. Teague, G. Hilmas, W.Fahrenholtz, Missouri Univ. of Science and Technology, USA

Pressureless sintering of W(Ta)C using oxide and carbide starting mate-rials yields a near fully dense object with reasonable room temperaturemechanical properties, however, secondary and tertiary phase forma-tion during sintering can inhibit the high-temperature mechanicalproperties. While X-ray diffraction showed only WC and W presentafter sintering, a third phase is apparent from SEM imaging. Using acombination of FIB specimen preparation and STEM analysis, all of therelevant phases were determined. Because of the relatively low atomicnumber of the C and O, STEM-EDS analysis was inconclusive, eventhough STEM-HAADF (Z-contrast) imaging revealed 3 distinct phases.EELS analysis of W(Ta)C or oxides is difficult due to the large differencein atomic number. Tuning the specimen thickness precisely with FIB al-lowed for STEM-EELS analysis, which revealed the presence of carbidesand oxides following processing. Oxide grains were completely isolatedfrom each other, eluding to incomplete carbothermal reduction.

Fundamentals & Characterization: Structure-Property Relationships in MultifunctionalMaterials

Structure-Property Relationships in Multi-FunctionalMaterialsRoom: 311Session Chair: Kevin Doherty, Army Research Lab

8:00 AMCharacterization of Al-based Alloyed Foams Containing SnFormed by Powder Metallurgical ProcessingL. Y. Aguirre Perales*, F. Jalilian, R. A. Drew, McGill University, Canada

Powder metallurgy is a route to produce Al foams with close-cellstructure. With foaming taking place in a short period of time, prob-lems of drainage and pore coalescence occur shortly after the beststructure is obtained. Previous studies by this research group haveshown that foaming Al with Sn can decrease the processing tempera-ture. A low density structure may be obtained by using lower temper-ature and longer times. This study presents the addition of third ele-ments (Ti and Ni) that generate an exothermic reaction with Al andSn during the foaming process decreasing the foaming temperature.DSC is used to characterize the powder mixtures, microstructuralcharacterization is done by SEM and macroscopic foam expansion

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 247

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania248

and pore shape morphology are also shown and compared. It wasfound that adding Ti aids the foam expansion, making foaming pos-sible at a lower temperature.

8:20 AMProperties of Al and Al-12Si Foams Produced from Ni-coated TiH2P. M. Proa-Flores*, R. L. Drew, McGill University, Canada

In the powder metallurgy aluminum foaming technique, several in-vestigations have been made to try to harmonize the foaming agenthydrogen desorption temperature with the aluminum meltingpoint in an effort to reduce unwanted phenomena such as pore co-alescence. Ni-coatings as diffusion barrier on the foaming agentpowders (TiH2) have been found to be helpful in delaying the hy-drogen desorption temperature of TiH2. Aluminum foams wereproduced following the powder metallurgy technique. Aluminumpowder (99.5% -345 mesh) and Al-12Si prealloyed powder (-345mesh) were mixed with 1%wt Ni-coated TiH2 powder. Compactsfrom both conditions were produced using hot uniaxial pressing(ρ≥99.3%) and foamed at 800°C for pure aluminum foams and 700and 750°C for Al-12Si foams. Foams produced from Ni-coated TiH2powders exhibited better pore structure homogeneity comparedwith the ones produced without coating. Al-12Si foams showedfiner pores and a greater tendency for drainage than pure alu-minum foams.

8:40 AMNanocrystalline Periodic Cellular MetalsG. D. Hibbard*, University of Toronto, Canada

Nanocrystalline periodic cellular metals can combine enhanced specificstrength and energy absorption capabilities at low density. These hybridmaterials were fabricated by electroforming high strength nanocrys-talline sleeves around periodic cellular (micro-truss) pre-forms. Thenanocrystalline structure was characterized directly by X-ray diffrac-tion and indirectly by microhardness mapping, while mechanical prop-erties were measured in uniaxial compression. It was found that trusscollapse occurred by an inelastic buckling mechanism and that the me-chanical properties were controlled by the sleeve thickness.

9:00 AMSynthesis and Electrical Properties of the Combined (V : Sn ; V : Ti; V : Co ; V : Ni) oxides by solid-state method (Invited)C. Kao*, H. Cheng, National Cheng Kung University, Taiwan

The combined oxides of vanadium(V) oxide-tin(IV) oxide, vana-dium(V) oxide-titanium(IV) oxide, vanadium(V) oxide-cobalttetroxide, and vanadium(V) oxide-nickel(II) oxide were prepared bysolid-state method. Vanadium is malleable and ductile, and resistantto corrosion by moisture, air and even most acids and alkalis at roomtemperature. The ratios of metal: metal(V : Sn ; V : Ti ; V : Co ; V :Ni) oxides are 2 : 1 ; 1 : 1`and 1 : 2, respectively. The better crys-tallinity of the powder occurred at 823 K for 20 h for V : Sn oxides asexamined by XRD. The other three (V : Ti ; V : Co ; V : Ni) oxides oc-curred at 923 K for 10 h.Calcined powders were tested for electricalresistivity and dielectric constant. The logarithm of DC electrical re-sistivity for ( V : Ti = 2 : 1) oxide 3.5 ohm-cm is the lowest.

10:00 AMDesign and Fabrication of Linear Cellular Alloys as Casings forStructural Energetic MaterialsD. A. Fredenburg*, T. M. McCoy, A. Jakus, J. Cochran, N. Thadhani, GeorgiaTech, USA

We are investigating Linear Cellular Alloys (LCAs), which are honey-comb-type structures made via powder extrusion for use as aerody-namic casings for ballistic delivery of energetic materials. Quasi-static and dynamic impact experiments are performed to generateconstitutive and failure properties of filled and unfilled LCAs underconditions of various stress states and strain rates. The LCA casingsare made of Maraging 200 steel with 9-cell waffle and pie-section cell

designs at ~25% relative density. Quasi-static compression testsshow similar initial deformation for both geometries, but significantdifferences in post-deformation failure strength. Instrumented gasgun impact experiments are also performed at 100-300 m/s to cap-ture transient deformation states, and compare with those predictedfrom numerical simulations, for validation of constitutive models.The key results from work performed to-date will be described inthis presentation.

10:20 AMPerforation Stretch Formed Periodic Cellular CopperE. Ng*, A. McLean, G. D. Hibbard, University of Toronto, Canada

Periodic cellular materials can combine structural and heat exchangefunctionalities at low mass. Periodic cellular copper, having relativedensities below 10 %, were fabricated by a stretch forming method inwhich alternating nodes of a perforated metal sheet precursor wereplastically deformed above and below the starting plane, creating athree dimensional truss structure. Mechanical properties were meas-ured in compression and microstructural characterization was con-ducted by electron backscatter diffraction. It was determined that thework hardening introduced during fabrication can be used to in-crease the specific strength and stiffness of the cellular architecture.

10:40 AMStructural Performance of Aluminum and Stainless SteelPyramidal Truss Core Sandwich PanelsK. Doherty*, A. Yiournas, J. Wagner, US Army Research Laboratory, USA

Future lightweight military vehicles will demand increasingly mass-ef-ficient structures to satisfy design requirements such as increased mo-bility and survivability. One possible family of lightweight structuresentails sandwich panels consisting of solid face sheets and a low densitycore. The sandwich structures can provide both structural strength andstiffness with load-bearing potential. In this study, sandwich panelsconsisting of metallic face sheets and a pyramidal truss core manufac-tured from either 6061-T6 or 316L stainless steel are investigated. Thestructures were subjected to panel bending and in-plane compressiontesting to explore the effects of relative core density and process param-eters. The mechanical response and failure mechanisms were catego-rized for the different structures and materials. Also, the processingchallenges associated with fabricating larger panels will be discussed.

11:00 AMTruss Core Sandwich Panel Performance Enhancement Enabled byNovel Discrete-Truss ArrangementsB. Langhorst*, D. Mumm, University of California, Irvine, USA

In recent years, truss-core sandwich panels have been optimized formultifunctionality based on homogeneous unit cell periodicity. Thisstudy examines novel truss arrangements and their correspondingoptimization routines which enable performance that surpasses thelimits of equivalent weight pyramidal truss arrangements. By offset-ting the trusses that comprise a traditional pyramidal unit cell, dis-crete-truss arrangements reduce the spans of unsupported face sheetareas which are susceptible to buckling. Experimental, numerical andtheoretical panel bending analyses are presented which demonstrate aperformance superiority of discrete-truss core sandwich panels overexisting technologies. Additionally, the heterogeneous core optimiza-tion possibilities that discrete-truss cores enable are demonstrated.

11:20 AMTexture and microstructure of BFO thin films analyzed by EBSDD. Goran*, Oxford Instruments HKL, Denmark; M. Es-Souni, C. Solterbeck,University of Applied Sciences of Kiel, Germany

The study aims to show the capability of the “Nordlys S” high resolutionEBSD detector and CHANNEL5 software to successfully analyse materi-als in thin films with trigonal crystal structures as the Bismuth IronOxide (BFO). The texture and microstructure of a pure BFO and a Mndoped BFO thin films were analyzed by EBSD. The results show that the

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 248

Th

urs

day

AM

www.matscitech.org 249

Mn doped BFO thin film has different microstructural and texturalcharacteristics compared to the pure BFO thin film. It was also experi-mentally found that the pure BFO and the Mn doped BFO thin filmshave very different magnetic and electric properties. The high resolutionof the “Nordlys S” detector was successfully used to solve the pseu-dosymmetry problems of the BFO phase. The EBSD technique is a pow-erful tool that can be used to study the influence of texture and mi-crostructure on the electrical and magnetic properties of BFO thin films.

11:40 AMMechanical Properties in relation to Fiber OrientationDistribution of two C/C compositeS. S. Iqbal*, P. Filip, Southern Illinois Univ. Carbondale (SIUC), USA

Mechanical properties through-the-thickness of 2D (material-A) and 3D(material-D) C/C-composites were investigated in relation to fiber-orien-tation-distribution (FOD). A direct correlation was found between FODand mechanical properties. Tensile strength of material-D was higherthan material-A. Material-A exhibited higher compressive strength andmodulus than material-D.Higher flexural strength and modulus were ex-hibited by material-A compared to material-D. Material-A possesseslower interlaminar strength than material-D which could be attributed todifferences between 2D-architecture of short-pitch-fibers in material-Aand 3D-architecture of continuous-ex-PAN-fiber in material-D as well asdifferences in interfacial-shear-strength between fiber and matrix. Uni-versally, material-D showed higher failure strain than material-A. Tough-ness of material-D was higher than material-A. SEM of fractured surfacesrevealed different fracture mechanism for two materials.

12:00 PMCompositionally and Structurally Graded CoCrMo–Ti6Al4V AlloyStructures for Bone ImplantsV. K. Balla*, W. Xue, S. Bose, A. Bandyopadhyay, Washington StateUniversity, USA

Novel structures with functional gradation in composition and struc-ture were successfully made in CoCrMo – Ti6Al4V combination usingLaser Engineering Net Shaping (LENS). Addition of fully dense, com-positionally graded CoCrMo alloy on porous Ti6Al4V significantlyincreased the surface hardness without any intermetallic phases.Based on in vitro biocompatibility, increasing the CoCrMo concen-tration on the surface reduced the live cell numbers after 14 days ofculture on its surface compared to base Ti6Al4V alloy surface. How-ever, these surfaces always showed better bone cell proliferation than100% CoCrMo alloy. Our talk will focus on LENS produced unitizedparts with functional gradation in composition and/or structure, andtheir mechanical, microstructural and wear characterizations. Thesestructures can eliminate need for multiple parts with different com-positions for load bearing implants such as total hip prosthesis.

Iron & Steel: Advancements in SteelProduction through EAF, Ladle Refining, andContinuous Casting Technologies andPractices

Advancements in Steel Production: EAF, LadleRefining, and Continuous Casting Technologies andPracticesRoom: 328Session Chair: Les Niemi, Affival Inc.

8:00 AMIntegrated process modeling of decarburization in RH-OB processY. Kim*, K. Yi, Seoul National University, South Korea

Various factors influence the decarburization reactions in the RHprocess of secondary steelmaking. In this study, we develop a 3D nu-merical model which may be utilized to comprehensively predict the

influence of each of these multiple variables. This model includes cal-culations of the decarburization reactions based on the circulating flowof Ar gas, as well as various decarburization mechanisms grounded onthermodynamics and kinetic theory. Furthermore, the model includesconsiderations of how the decarburization reactions are influenced byparameters such as oxygen incorporation into the melt through OBjets and from the slag, and the effects of variations in the surface geom-etry. The validity of the model has been verified through comparisonswith experimental data gathered from actual processing systems.

8:20 AMDe-oxidizing Behaviors of Al and Ti in Fe-melts under HighTemperaturesC. Wang*, H. Matsuura, S. Seetharaman, Carnegie Mellon University, USA

As part of an investigation into the transient ladle-reaction products thede-oxidation of Al and Ti in Fe-melts are studied at higher temperatures,i.e. 1923K and 1973K, in lieu of the general executed 1873K. The investi-gation is carried out through sampling in a vacuum-induction furnaceand the inclusion population is characterized as function of time. It is re-vealed that elevated operation temperature will promote the formationof Al2TiO5, which constitutes the majority of inclusions immediatelyafter Ti addition but the inclusion chemistry evolves with time towardsthe thermodynamically stable Al2O3. It is found that the inclusion shapeappears to, as a result of the transient and temporary Ti-oxidation, un-dergo a permanent change from spherical and polygonal morphologytowards irregular ones. Influences exerted by possible existence of liquidinclusion are also discussed with respect to thermodynamic predictions.

8:40 AMOptimized Slag Analysis Using Energy Dispersive X-rayFluorescence Analysis (EDXRF)A. Seyfarth*, J. Jackson, D. Pecard, Bruker AXS Inc., USA

Slag analysis using X-ray fluorescence spectrometry (XRF) is an excel-lent, cost effective method to determine the elemental compositionand used to control dosage of additives to achieve best performance.To reduce time to result it is imperative to minimize analysis, prepara-tion and turn around time. This can be achieved by performing theanalysis as close to the source as possible: EDXRF Systems placed in thefurnace area have to be rugged and small. New detector technology, thesilicon drift detector (SDD), enabled the design of a new class of benchtop ED XRF systems. The talk will illustrate the performance of EAFand LMF type slag analysis using a state of the art bench top EDXRFsystem (S2 RANGER). All steps from sampling to results transmissionwill be discussed. Accuracy and Repeatability and stability data isshown as well as implementation examples throughout the US.

9:00 AMNew Observation of Inclusions in SteelL. Zhang*, Missouri Univ. Sci. Tech., USA

Inclusions in different steels were extensively observed through opti-cal microscope and SEM. Partial acid extraction was used to revealthe 3-dimensional morphology of inclusions. Different precipitatedphases inside inclusions were analyzed. The biggest contributions ofthe current research include: 1). New 3-dimensional morphology ofinclusions were found, such as box shape, plate shape etc. 2). The en-gulfment into the steel dendrites, entrapment into the space betweensteel dendrites, and pushing to the tip of steel dendrites were clearlyrevealed. Generation of these inclusions was theoretically discussed.

9:20 AMFluid Flow and Inclusion Motion in the Holding Furnace of a Two-strand Horizontal Continuous CasterS. Yang, J. Li, Univ. Sci. Tech. Beijing, China; L. Zhang*, K. Peaslee,Missouri Univ. Sci. Tech., USA; S. Shi, Z. Zuo, Hengyang Hualing SteelTube Co Ltd, China

Fluid flows and inclusion motion in the holding furnace of a two-strand horizontal continuous caster were investigated with physical

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 249

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania250

modeling and mathematical modeling. The holding furnace was re-designed according to the residence time, response time, fraction ofthe dead zone, prevention of short-circuit flow, inclusion removal,and temperature distribution, etc. The redesigning is to optimize theheight of the furnace, the impact board/box, dams, and the outlets.Inclusions in the horizontal continuous billet were investigated forthe original and optimized holding furnace, indicating that the opti-mized furnace could removal more inclusions, ad thus the billets hadbetter cleanliness.

10:00 AMEffect of BaO on the Properties of Continuous Casting Mold FluxQ. Huang, Q. Wang, Chongqing University, China; L. Zhang*, MissouriUniversity of Science and Technology (Missouri S&T), USA; B. Xie, S. He,Chongqing University, China; X. Lu, Missouri University of Science andTechnology (Missouri S&T), USA

Mold flux plays a key role for the quality of steel during continuouscasting. Due to the peritectic reaction for the crack sensitive medium-carbon steels, there is a conflict between heat transfer and lubrication,and this is hard to comprise. So far, the solution for this issue is to usefluoride-bearing mold flux. However, fluoride-bearing mold fluxgenerates environment pollution and corrosion of the mold copperplate. In the current study, BaO is used as the alternative crystallinephase rather than the fluoride. The morphology of crystalline phasesin the mold flux are detected using Scanning Electron Microscope(SEM) and Energy Dispersive Spectroscopy (EDS), and the thermaldiffusivity of the flux is measured to evaluate its capability of heattransfer. Experimental data indicate that BaO can improve the lubri-cation ability of the film of molten flux, and prevent the formation ofcuspidine phase.

10:20 AMA Numerical Simulation of the Thickness of Liquid Flux layer inContinuous CastingE. Ko*, K. Yi, Seoul National University, South Korea

The aim of this study is to analyze the the shape of the liquid fluxlayer formed between the solid shell and the mold in continuous cast-ing systems. Because of difficulties in direct experimental observationof the flux film, a numerical analysis model of fluid flow patternswithin the film is used to investigate these effects. Particular emphasisis placed in this study on the impact of various factors on pressureforces involved with compensating the ferrous static pressure of thecast steel. These factors include the thickness of the liquid flux filmand the thickness difference along the length of the film. The analysisreveals that the shape of the liquid film shape is not uniquely decidedby the force balance between the static pressure of the cast steel andthe internal pressure of the film.

Iron & Steel: Steel Product Metallurgy andApplications

Property - Application StudiesRoom: 330Session Chair: Dibyajyoti Aichbhaumik, U.S. Dept. of Energy

8:00 AMInnovative Induction Heat Treating TechnologiesV. Rudnev*, D. Brown, G. Doyon, Inductoheat, Inc., USA

This presentation focuses on:• Novel approaches to induction heat treating of critical automotive

components, including but not limiting to induction contour hard-ening of spiral, hypoid and bevel gears with diameters from 6” to 8”(patent pending) and sprockets.

• Patented CrankPro Technology for non-rotational hardening andtempering of crankshafts (V-4, V-6 and V-8) and camshafts withnon-convention journals and lobes.

• Specifics of induction hardening of wrench jaws, hammers, fasten-ers, tools.

• Induction heating of large-diameter (8 to 12 in. and larger) billetsmade from carbon steels, stainless steels and Inconel, including acomparative assessment of progressive multi-stage horizontal in-duction heating approach vs. static heating using vertical inductors.

• FluxManager® - technology for effective heating of carbon steel tu-bular goods (patented in 2007).

• Developing compact and highly-efficient induction tempering andstress relieving systems.

8:20 AMEffect of Temperature and Strain Rate on Secondary PhaseFormation in 2205 Dual Phase Stainless Steel under Hot WorkingConditionH. Keshmiri, M. Shahhosseini, Esfarayen Industrial Complex, Iran; A.Shahhosseini*, University of Louisville, USA; G. Ebrahimi, Tarbiat MoallemSabzevar University, Iran

Exceptional combination of strength and toughness properties to-gether with good corrosion resistance under critical working condi-tion is promoting dual phase stainless steels as suitable alternative toconventional austenitic stainless steels. This is particularly true in oilextraction, paper manufacturing and, in general, chemical industries.Due to their two-phase microstructures, these alloys combine the de-sirable properties of austenitic and ferritic stainless steels. The princi-ple aim of this work is to study the effect of temperature and strainrate on secondary phase formation such as sigma phase during andafter high temperature deformation. For this purpose sigma precipi-tation in an 2205 dual phase stainless steel has been investigated dur-ing and after uniaxial compression test at various temperatures from800C to 1000C with T=50K and true strain rate ranging from 0.001to 0.8 s-1.

8:40 AMEffect of Aging Temperature on Microstructure and MechanicalProperties of 2205 Duplex Stainless SteelH. Keshmiri, M. Shahhosseini, Esfarayen Industrial Complex, Iran; A.Shahhosseini*, University of Louisville, USA; G. Ebrahimi, Tarbiat MoallemSabzevar University, Iran

Duplex stainless steels (DSS) referred to as a ferritic-austenitic steels,combine many of the beneficial properties of ferritic and austeniticsteels. These steels offer good resistance to pitting and uniform corro-sion. However, intermetallic phases can also form during casting orhigh temperature processing and can degrade the properties. Thesesteels possess a combination of properties; high strength and corro-sion resistance that is not readily attainable using conventional singlephase austenitic or ferritic stainless steels. The purpose of this re-search is to investigate the behavior of 2205 duplex stainless steel inmicrostructure and mechanical properties under the conditions ofsolution annealing followed by water quenching then aging at varioustemperature in the range of 350C to 900C with T=50K. The evolutionof the microstructure, mechanical properties, and chemical composi-tion of secondary phases in relation with time and temperature arepresented.

9:00 AMInvestigation of Hot Deformation Behavior of 1.4563 Super-Austenitic Stainless SteelH. Keshmiri, M. Shahhosseini, Esfarayen Industrial Complex, Iran; A.Shahhosseini*, University of Louisville, USA; G. Ebrahimi, Tarbiat MoallemSabzevar University, Iran

1.4563 is a super-austenitic stainless steel with very high nickeland chromium contents. The alloy behaves particularly well insulphuric and phosphoric acid environments, even when contam-inated by chlorides and fluorides species. The combinedchromium and molybdenum additions increase the localized cor-rosion resistance drastically. The alloy is extensively used in chem-

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 250

Th

urs

day

AM

www.matscitech.org 251

ical and offshore applications including very sour gas field. Thepurpose of this research is to investigate hot deformation behaviorof 1.4563 steel. For this reason, hot compression tests were per-formed. The temperature was varied in the range from 900C to1150C with T=50K, while the strain rate was varied from 0.01 to0.8 s-1. The mean flow stress (MFS) was fitted to the hyperbolicsin function proposed by Sellars and Tegart. Activation energy forplastic deformation and grain size variance was measured as afunction of processing temperature at a nominal strain rate 0.01to 1 s-1.

9:40 AMEffects of Paint Baking on the Axial Crash Behavior of AdvancedHigh Strength SteelsT. Link*, United States Steel Research, USA

Advanced high strength steels (AHSS) offer an attractive combina-tion of strength and formability as well as the potential for improvedautomotive crashworthiness. However, under severe impact loadingconditions, spot weld and base metal failures can occur in someAHSS. The axial crash behavior of a range of steels is studied by droptower testing, and the effects of simulated paint baking thermal cycleson crash performance are examined. Local formability analyses areincluded to understand better the effects of paint baking on deforma-tion and fracture. The results show that paint baking can improve thefracture resistance of AHSS by martensite tempering. However, theeffects are generally not large enough to be manifested in the axialcrash performance of spot welded components.

10:00 AMThermo-mechanical crack generation and ultra-fine grainsformation in carbon steel railway wheels under continuouscontact load and repeated heat inputK. Handa*, Railway Technical Research Institute, Japan; Y. Kimura, Y.Mishima, Tokyo Institute of Technology, Japan

Elucidation of the mechanism how tread thermal cracks generateduring the service is important to improve the safety design of carbonsteel railway wheels. In the present work, we have succeeded to repro-duce the thermal cracks using actual railway wheels under the condi-tion of concurrent loading of both continuous rolling contact and re-peated frictional heat. Microstructural observation was preciselyconducted with the electron back-scattered diffraction analysis. Wehave found that ultra-fine grains of ferrite and spheroidized cemen-tite are formed in the area within 100 μm depth from the surfacewhere fine cracks are also observed being initiated. Relations of resid-ual stress, cracks configuration and fracture surface were examined toconsider the crack generation process. Plastic deformation and ther-mal stress near the surface result in substantial tensile residual stress,which causes initiation and propagation of cracks.

10:20 AMFinite Element Analysis of Deformation Behavior of Hot RolledSheet after Coiling Considering TRIPH. Cho*, Y. Cho, H. Han, Seoul National University, South Korea; Y. Im, J. Lee,J. Kwak, POSCO, South Korea; S. Ryu, Seoul National University, South Korea

Asymmetric contraction of hot rolled sheet after coiling is very seri-ous problem in a manufacturing process. TRansformation InducedPlasticity(TRIP) could be responsible for this asymmetric behaviorbecause it is known that asymmetric contraction is associated withthe phase transformation after coiling process. In this study, a finiteelement model was developed to simulate asymmetric contraction ofthe coil. Finite element calculations have been carried out for highcarbon steels and high alloy steels by considering the phase transfor-mation and the TRIP phenomenon. Using the model, asymmetriccontractions of the coil were successfully simulated and degrees ofasymmetric contraction for various conditions were compared witheach other. Tendencies of asymmetric contraction are in good agree-ment with experimental data.

10:40 AMDevelopment of friction welded shaft for the turbocharger ofmarine diesel engineM. Han*, I. Kim, Y. Yoon, E. Kim, Hyundai Heavy Industries Co., Ltd, SouthKorea; J. Kim, KOREA Special Precision Co, South Korea

Friction welding process is widely applying for bonding of sameor different kinds of metallic materials due to high productivityand cost reduction. In this study, a manufacturing process of tur-bocharger shaft, including forging of disk head, friction weldingof shaft and head and heat treatment, has been established. Fromthe FE analysis on the forging process of disk head, the optimumdimension of round bar was determined. The friction welding pa-rameters and heat treatment conditions were selected from inves-tigating the effect of several variables on the quality of weldedpart. Applying the optimized conditions to actual production, thefriction welded shaft for turbocharger could be manufacturedsuccessfully.

11:00 AMInvestigation of Zinc Thermal Diffused Coatings by Solid StateDiffusion MethodG. Heidari, M. Mosavi khoei, A. Hasanzade, P. Hoveidamarashi, AmirkabirUniversity of Technology, Iran; H. Keshmiri, Esfarayen Industrial Complex,Iran; A. Shahhosseini*, University of Louisville, USA

One of the most destructive effects of environment on the metalsurface is corrosion. The metal surface can be protected againstcorrosion by forming a high corrosion resistance layer such aszinc coating. In this research, zinc coating on St37 steel sampleswere formed by thermal diffusion zinc coating method. The sub-strate sample in contact with powder mixture was heated in resist-ant furnace using both rotary and fix states. Surface characteris-tics were studied by optical and scanning electron microscope.Corrosion resistant was evaluated by potantiodynamic polariza-tion technique in 3.5 wt% NaCl. The present phases in the surfacelayer were identified using XRD analysis. The results showed thatthe layer formed by 95:5 Zn:Cr2O3 powder mixture at 375±10 °Cfor 2-3 hours had superior corrosion resistant and the layerformed using rotary state had higher quality than layer formed atfix state.

Materials & Systems: Advances in Biomedicaland Biomimetic Materials

Nanoparticles for Medical Diagnosis and TreatmentRoom: 333Session Chair: Donglu Shi, University of Cincinnati

8:00 AMIn vivo imaging with fluorescent superparamagnetic nano spheres(Invited)D. Shi*, H. Cho, C. Huth, Z. Dong, University of Cincinnati, USA; Y. Chen,Institute for Biological Sciences, Chinese Academy of Science, China; H. Gu,H. Xu, Shanghai Jiao Tong University, China; W. Wang, G. Liu, ArgonneNational Laboratory, USA; J. Lian, L. Wang, R. C. Ewing, University ofMichigan, USA

A critical challenge of nanotechnology in biomedical applications hasbeen the development of multi-functional nanostructures. For cancerdiagnosis and treatment, the challenge often originates from complexnanostructures that entail both intense emissions and other function-alities such as drug storage and therapeutic means. We report here ascheme of novel nanostructure design that ideally satisfies these im-portant requirements. By surface functionalizing magnetic Fe3O4composite nanospheres with quantum dots, in vivo soft tissue imag-ing was realized in mice for the first time. The conjugated quantumdots on magnetic Fe3O4 composite nanospheres (MNS) exhibited

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 251

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania252

intense visible light emissions in both fluorescent spectroscopy andanimal in vivo imaging. In vitro hyperthermia experimental resultsindicated effective heating of the MNS, resulting from the applicationof alternating electromagnetic field. The experimental results pre-sented in this study show promise in cancer diagnosis and treatment.

8:20 AMModeling the Electrochemical Interactions of NanoparticulateSystems in Medical DevicesD. Saylor*, B. Dair, U.S. Food and Drug Administration, USA; J. Guyer, J.Warren, National Institute of Standards and Technology, USA

Over the past decade, approximately $5 billion per year has beenspent on nanotechnology research and development. These burgeon-ing technologies have already been incorporated into medical de-vices. Nanoparticulate silver has been used in wound dressings, surgi-cal masks, and catheter coatings as an antimicrobial agent. Tounderstand and quantify the physicochemical phenomena associatedwith nanostructuring and the potential clinical implications, we havedeveloped a phase field model to predict the behavior of these sys-tems in electrochemical environments. Specifically, we focus on silvernanoparticles in ionic solutions. Calculations have been used to eluci-date the impact of particle size, solution concentration, and particleaggregation on ion release and surface charge, which impact antimi-crobial efficacy, system stability, and, potentially, biocompatibility. Wealso assess the affect of particle distribution and substrate chemistryon the performance of nanoparticulate coatings.

8:40 AMMagnetic Nanoparticle Heating for Hyperthermia TreatmentI. Baker*, G. Zhang, Q. Zeng, J. A. Loudis, P. J. Hoopes, J. Weaver, R. R.Strawbridge, Z. E. Pierce, J. Tate, J. Ogden, Dartmouth College, USA

Nanoparticles for cancer treatment via magnetic hyperthermia ide-ally develop sufficient heating at the lowest possible frequency andthe smallest external magnetic field strength. We will compare boththe structure, and the magnetic and heating behavior of coated Fe/Feoxide core/shell composite nanoparticles to that of several differentsizes of dextran-coated iron oxide nanoparticles. The Fe/Fe oxidenanoparticles were synthesized to utilize the fact that the high satura-tion magnetization of an iron core (120-190 emu/g, twice that of ironoxide) could give a greater heating effect than iron oxide nanoparti-cles, while the iron oxide coating will allow the nanoparticles to beobserved using magnetic resonance imaging so that therapy can beeffectively monitored. In vivo studies on tumors in mouse models di-rectly injected with nanoparticles will also be presented. Supportedby NIST Grant 60NANB200120, the Nanocancer Working Group atDartmouth and the Norris Cotton Cancer Center Prouty Pilot Pro-ject Program.

9:00 AMLiposome-Quantum Dot Hybrids as Multimodal Therapeutic andImaging Agent Delivery SystemsW. T. Al-Jamal*, K. T. Al-Jamal, K. Kostarelos, School of Pharmacy/University of London, United Kingdom

Quantum dots (QD) have been widely explored as fluorescent probefor multiplexing imaging purposes. In this communication, we pres-ent the construction of Lipid-QD (L-QD) hybrid by incorporationorganic CdSe/ZnS QD within a variety of lipid bilayers, self assem-bling into small unilamellar vesicles. These L-QD hybrids renderedQD compatible with the aqueous environment, fluorescently labelledthe lipid bilayers and enhanced QD optical stability during storageand exposure to UV irradiation. The L-QD vesicles sucessfully la-belled tumor cells in vitro and tumor xeongrafts in vivo. Moreover,these novel L-QD hybrids showed high stability in vivo and differentbiodistribution profiles have been observed depending on the lipidbilyer characteristics. The L-QD hybrid presented here are thought toconstitute a novel delivery system that offers the potential for trans-

port of combinatory therapeutic and diagnostic modalities to cancercells in vitro and in vivo.

Bioceramics IIRoom: 333Session Chair: Donglu Shi, University of Cincinnati

10:00 AMMicrowave Synthesis of Nanocrystalline HydroxyapatiteS. J. Kalita*, S. Verma, University of Central Florida, USA

Nanocrystalline bioceramics are a new rage in bone tissue engineer-ing. Here, we synthesized bioactive hydroxyapatite (HAp) powder inthe lower-end of nano-regime using microwave radiation, which of-fers several advantages. The powder was synthesized using calciumnitrate tetrahydrate and sodium phosphate dibasic anhydrous asstarting materials. The microwave power of 600 W and mole ratio ofCa/P in the starting chemicals, served as the factors in HAp synthesis.The powder was characterized using XRD, SEM, HR-TEM, EDS,TG/DTA and FT-IR techniques. Results established a highly crys-talline 5-30 nm powder with elemental composition of Ca & P inHAp phase, which possessed mixed (elliptical and rod-shape) mor-phology. The average crystallite size was 12 nm. FT-IR confirmed ap-atite structure of the powder. TG analysis showed 23% weight-lossupon heating up to 1200°C , contributed by the removal of ad-sorbed/lattice water, and decarboxylation of HAp. Remarkably lowerinitial dehydroxylation temperature (570°C) was observed.

10:20 AMNanoindentation of Biomaterials – new concepts in biomechanicalcharacterization (Invited)M. E. Dickinson*, Hysitron Inc., USA

Nanoindentation is a popular technique for the mechanical charac-terization of materials and more recently it has been used to study bi-ological tissues and biomaterials. Traditionally quasi-static nanoin-dentation was used to measure hardness and modulus however thestandard models assume an elastic-plastic material which does notapply to most biomaterials. Developments in nanoindentation suchas dynamic testing enabled the measurement of visco-elastic re-sponses in realistic environments such as controlled temperaturesand fluids. Recently the capabilities of accurate force and displace-ment control has led to some interesting work using nanoindentationin non-standard routines. This talk will show the developments innanoindentation of biological tissues from the standard techniques tothe more unusual testing methods. Testing of tissues from bones andteeth, to soft tissues and cells will be shown and examples of somenovel test methods such as adhesion and cell bursting will be given.

10:40 AMNanomechanical and structural characterization ofhydroxyapatite coatings on ultrafine grained titaniumK. Calvert-Doyle*, K. P. Trumble, S. Chandrasekar, C. Saldana, W. Moscoso,Purdue University, USA

Due to its high strength, many metal orthopaedic implants are com-monly made of Ti-6Al-4V despite the potential leaching of cytotoxicaluminum and vanadium. This research focuses on increasing thestrength of commercially pure titanium by grain refinement and ex-plores the possibility of coating these materials with hydroxyapatitefor orthopaedic uses. Grade 2 & 4 CP-Ti UFG plates were developedwith strains of up to 3.4 using an LSEM process. Hydroxyapatite coat-ings were applied to the UFG titanium plates using two processingroutes. The hardness increased approximately two times with the as-sociated refinement of the grain and substructure. Recrystallizationstudies were conducted using differential scanning calorimetry, met-allographic analysis and hardness measurements. Preliminary resultsindicate that recrystallization begins at 340°C. These results will bediscussed in the context of microstructure development during theapplication of hydroxyapatite coatings.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 252

Th

urs

day

AM

www.matscitech.org 253

11:00 AMPulsed Laser Induced Ca-P Coatings on Ti- 6Al-4V for Hip Bio-implantS. R. Paital*, The University of Tennessee, Knoxville, USA; N. B. Dahotre, TheUniversity of Tennessee, USA

The feasibility of depositing a tailored biomimetic Calcium Phos-phate (Ca-P) coating on Ti-6Al-4V substrate by using a pulsedNd:YAG system has been explored. The formation of different tex-tures were obtained by varying the spot overlap with change in lasertraverse speed. X-ray diffraction studies revealed the formation of α-TCP, TiO2, Ti and Al as the major phases. Mechanical integrity of thecoated samples is evaluated by both an instrumented nano indenta-tion technique and wear studies in a simulated bio environment. Ki-netics of bioactivity is studied to understand the driving force for nu-cleation and precipitation of hydroxyapatite on substrate materialfollowing immersion in a simulated bio-fluid (SBF). SEM analysiscoupled with the EDS spectra revealed both the morphology andchemical composition of the samples before and after immersion inSBF. Contact angle measurement studies proved the bio-texturedcoated samples to be hydrophilic as compared to the bare Ti-6Al-4V.

Materials & Systems: Enabling SurfaceCoating Systems: Science and Technology

Advanced Processing and ModelingRoom: 335Session Chairs: Rodney Trice, Purdue University; PravansuMohanty, University of Michigan

8:00 AMSpray formation and evolution in coating processes (Invited)P. E. Sojka*, Purdue University, USA

Sprays are employed in coating processes to distribute mass evenlyover a surface. This is true when painting, applying thermal barriercoatings, and layering of bio-related materials such as when manufac-turing pharmaceutical tablets. Coating related spray formation andevolution can be divided into five steps: formation of a sheet/jet froma bulk liquid, breakup of the sheet/jet into ligaments, subsequent lig-ament breakup into drops, drop fragmentation/motion, drop colli-sions/coalescence/evaporation, and drop impact /spreading on a tar-get. Models of varying levels of sophistication are available to describeall five steps. Those applicable to cases where coating rheology iscomplicated (elasticity in paints, yield stresses in TBCs, and shearthinning in tablet coatings) are described. Three examples are pre-sented: drop formation from elastic filaments that break up under theinfluence of surrounding air, fragmentation of electrically chargeddrops, and impact of shear thinning coatings onto a tablet surface.

8:40 AMLow Pressure Cold Spray - Powder Shock Consolidation ProcessE. Leshchinsky, R. Maev*, M. Lubrick, University of Windsor , Canada

Understanding the complex mechanical behavior of particle rein-forced metal–matrix composites is important for engineering applica-tions. The focus of this research was on gaining a fundamental under-standing of the structure/property relationships that exist incomposites made by new emerging technique – Low Pressure ColdSpray. While composition is one of the key parameter in determiningthe final microstructure, the specific powder shock consolidation pa-rameters ( particle velocity, particle-gas mass flow ratio and gas tem-perature) were found to have significant effects on the development ofcomposite structure formation. Microstructural examination revealedthat adiabatic shear band formation and recrystallization phenomenaat the interparticle contacts lead to large differences in the ensuing mi-crostructure resulting in significant differences in these properties.The structure-property relationship based on physical model of adia-batic shear band formation will be presented and discussed.

9:00 AMLow pressure Cold Spray Consolidation and Sintering Near-NetShape Sliding ComponentsE. Leshchinsky*, E. Maeva, M. Lubrick, University of Windsor , Canada

Thermal spraying processes are well known in the industry for provid-ing relatively dense components. The Cold Spray (CS) technologies area growing alternative, especially after the great success of certain appli-cations such as plasma and thermal spray formed components. One ofthe advantages of the CS is the possibility to obtain complex thin-walledshapes of various powder materials and composites. The optional post-spraying processes such as sintering, sizing and little machining may beapplied. Using the low pressure radial injection CS method, some newthin wall components have been formed. The process involves the auto-matic mechanical removal of sprayed ring components from a mould.Both the structure and properties of powdered material along with theCS technology itself were studied. The main spraying and sintering pa-rameters were found to achieve high accuracy of components, which al-lowed the realization of a large scale CS forming-sintering technology.

9:20 AMCharacterization of pure Cu, Ni and Ti coatings produced by coldspray after heat treatmentA. Rezaeian*, McGill University , Canada; E. Irissou, J. Legoux, NationalResearch Council Canada(NRC), Canada; S. Yue, McGill University , Canada

The cold spray process produces a coating by mechanical deformation ofsprayed particles. This heavily cold worked structure needs recrystalliza-tion heat-treatment in order to gain back the deformability and ductilityof the materials. The effect of heat treatment of cold sprayed on mild steelas substrate coatings was investigated for three different pure powders:copper, titanium and nickel. As-sprayed coatings were annealed for onehour at a range of temperatures up to 800 °C. These were then comparedto as-sprayed specimens in terms of microstructure,hardness,and poros-ity. It was found that restoration processes in Cu coating were observed atabout 150 °C where the hardness of heavily cold deformed pure copperstarted to decrease. The corresponding temperatures were around 400° Cand above 800 °C for pure Ni and Ti, respectively. These materials werecompared in terms of deformability as well as annealing behaviors.

Multifunctional Coatings IRoom: 335Session Chairs: Rodney Trice, Purdue University; PravansuMohanty, University of Michigan

10:00 AMSurface Modification by Direct Metal Deposition Process:Technical Challenges, Opportunities and Performance Benefits(Invited)B. Dutta*, POM Group Inc., USA

This presentation will give an overview of the DMD process high-lighting the benefits of the process over conventional technologies.Special emphasis will be given to the ability of DMD process to cladvery dissimilar materials. Case studies, elaborating the challenges andbenefits of this near net shape process on dissimilar material claddingwill be presented. Hardfacing involving cermet composites and coat-ings for high temperature applications will also be discussed.

10:40 AMDevelopment of Titanium Nitride films on Titanium and Ti-6Al-4V Alloy using Laser Generated PlasmaR. Akarapu*, S. M. Copley, J. A. Todd, Pennsylvania State University, USA

Ti-6Al-4V alloy fan/compressor gas turbine blades may experiencesevere structural damage due to ingestion of hard particles, particu-larly during take off and landing. This is a leading contributor to themaintenance and repair of military jet engines. In this paper, we ex-plore the deposition of a titanium nitride coating on titanium and Ti-6Al-4V alloy, using CO2 laser-generated plasma. Temporally resolved

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 253

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania254

optical emission spectroscopy was used to identify the species in theplasma as a function of laser deposition conditions. The depositedlayers were characterized using optical and scanning electron mi-croscopy, energy dispersive spectroscopy (EDS), X-ray diffraction,and hardness measurements. XRD confirmed that near-stoichiomet-ric gold-colored TiN trails, 200 μm deep and 800 μm wide, could bedeposited at ambient pressure and overlapped to create a TiN contin-uous surface layer. This technique exhibits potential for rapid repairof Ti-6Al-4V gas turbine blades.

11:00 AMNon-immersion surface preparation for cerium-based conversioncoatings on aluminum alloy substratesW. Gammill*, M. O’Keefe, W. Fahrenholtz, Missouri University of Scienceand Technology, USA

The spray deposition of cerium based conversion coatings onto highstrength aluminum alloys is sensitive to the surface preparation of thesubstrate. Normally, substrates are prepared for coating using immer-sion cleaning methods in acid and base solutions. In this study, non-immersion surface preparation methods were studied. Cerium basedconversion coatings were deposited on substrates prepared by abra-sion, chemical-mechanical polishing, and alternative solution deliv-ery methods. Coatings were evaluated by optical and electron mi-croscopy, chemical and structural analysis, and corrosionperformance in neutral salt spray testing. Results indicate that alter-native methods can be successful but the coating formation and per-formance are dependant on the surface preparation method.

11:20 AMCoatings to Improve Surface Properties of Microcellular andFibrous Carbon StructuresA. Karumuri*, D. Sharma, S. M. Mukhopadhyay, Wright state university, USA

Formation of continuous and adherent ceramic coatings such as nitrides,carbides, and oxides on carbon structures can enhance many surfaceproperties such as high temperature oxidation resistance, heat exchange,and bonding with other phases. Most currently used coating methods usecomplex vapor phase depositions involving toxic chemical precursorsand undesirable by-products. The goal of this project is to investigatesimple,non-toxic thin film deposition techniques that use benign precur-sors and/or nanoscale particles on uneven high porosity graphite struc-tures with a variety of oxidation resistant compositions. Carbon foamsand fiber fabrics were coated with BN, SiC, Silica, and mixed phases. Theeffectiveness of each coating in surface property enhancements have beenstudied, and will be presented. Microstructure, composition, and chemi-cal states have been characterized by Field Emission Scanning ElectronMicroscopy (FESEM) and X-Ray Photoelectron Spectroscopy (XPS).

Materials & Systems: InternationalSymposium on Innovative Processing andSynthesis of Ceramics, Glasses andComposites

Composite and Powder ProcessingRoom: 336Session Chair: Chen-Feng Kao, National Cheng Kung University

8:00 AMA Comparison of Aqueous and Organic Routes to StructurallyCubic or Pseudo-Cubic Nanoparticles of Hafnia, Zirconia, andtheir Mixed OxidesS. Chan*, C. Lu, J. Raitano, J. Tang, M. Steigerwald, L. Brus, ColumbiaUniversity, USA

Nanoparticles of hafnia, zirconia, and their mixed oxides have beenprepared with cubic or pseudo-cubic structures using either aqueousor organic synthesis routes. The former is a two-step process involv-

ing formation of amorphous oxides and subsequent homogenizationand crystallization in a reducing environment. The latter is a single-step process involving cross-condensation. Both sets of products havebeen studied by HRTEM and XRD and exhibit similarities in latticedimensions and in their rounded morphology. The differences will beconsidered as well, focusing on the role of the reducing gas in the for-mer method and the elevated level of oxygen vacancies in these sam-ples suggested by a XANES redshift of 0.5eV at the Hf LIII edge forthe cubic nanoparticles relative to a monoclinic standard. The con-centration of oxygen vacancies will be probed by pyncnometry inconjunction with XRD.

8:20 AMHigh Purity Nanopowders for Transparent Ceramics: YAG, Spineland YttriaY. Tang*, L. Nguyen, H. Bui, S. Paras, J. Hong, T. Stefanik, R. Ericksen,Nanocerox Inc., USA

Nanocrystalline YAG, spinel and yttria powders are produced byNanocerox using Liquid Phase-Flame Spray Pyrolysis (L-FSP), with<200ppm total impurities. As produced YAG powders have 20-100 nmprimary particle size, and are largely free of hard aggregates. The pow-ders have a defect-hexagonal structure that converts to the garnet phaseupon calcination at 1100C. Calcined powders were freeze-granulated-dried with binders, surfactants and sintering aids. The granulae werethen pressed into pellets, vacuum sintered, and hot isostatic pressed(HIPped). The resulting transparent polycrystalline YAG ceramic ex-hibited 84% theoretical transmission at 1064 nm, <5 microns grainsize, and 339MPa strength (ring-on-ring biaxial test). Large transpar-ent YAG parts (100x110x12mm) were fabricated from such granulae.Neodymium doped polycrystalline YAG ceramics have also been pro-duced and demonstrated lasing capability. Spinel and yttria nano pow-ders have been processed into highly translucent materials as well.

8:40 AMAlmatis Implementation of a globalized method of particle sizemeasurement for calcined and reactive alumina’sC. Compson*, R. McConnell, T. Bullard, B. Smith, Almatis Inc, USA; N.Grossmann, B. Kruft-Steuler, Almatis GmbH, Germany

As Almatis introduced the concept of global products, we recognizedthe necessity for global quality control instrumentation, particularlyfor particle size measurement. Therefore, Almatis implemented aglobal approach for particle size determination using laser light scat-tering technique. The process of choosing a global instrument will bediscussed, with particular focus on the requirements for accuratemeasurement of calcined and reactive aluminas for the ceramics in-dustry. The range of Almatis products and their use in ceramics ap-plications will also be outlined.

9:00 AMThe Effect of Water-Soluble Polymers on the Microstructure andProperties of Freeze Cast CeramicsC. Pekor*, I. Nettleship, University Of Pittsburgh, USA

Freeze cast alumina ceramics were processed in the presence of varyingamounts of two different water soluble polymers. The first polymer isreported to preferentially adsorb to the prismatic planes of hexagonalice crystals (polyvinyl alcohol). The second polymer, polyethylene gly-col, shows no preferential adsorption. The effect of the polymers on themicrostructure and properties of freeze cast alumina were examinedand correlated to changes in the morphology of the growing ice crystals.

9:20 AMMechanical Behavior of Al-Al85Ni10La5 in situ Nanocompositesby Mechanical MillingZ. Zhang*, T. Topping, Y. Zhou, E. J. Lavernia, University of California,Davis, USA

Nanocrystalline intermetallic phases (Al3Ni, Al11La3) formed inamorphous Al85Ni10La5 powder via crystallization exhibit remark-

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 254

Th

urs

day

AM

www.matscitech.org 255

able thermal stability due to the low diffusivity of La and Ni in Al. Inthis study, Al-matrix nanocomposites (grain size ~200 nm) are syn-thesized via in situ crystallization of amorphous Al85Ni10La5 phaseusing a powder metallurgy route. The amorphous phase is intro-duced using two approaches. First, the amorphous powder is directlyblended with nanostructured Al powder. Second, the amorphouspowder is cryomilled with atomized Al powder. The mechanical be-havior is studied following different annealing treatments (200-500°C) and the composites reveal good mechanical and microstructurestability against thermal exposure. It is found that the yield strength ishigher than the rule-of-mixture estimation based on the correspon-ding Al85Ni10La5 and Al-matrix phases and such efficient strength-ening effects are discussed in the framework of mechanistic modelsfor composites.

10:00 AMPerformance of Composite Materials in Corrosive ConditionsD. M. Hill*, DNV Research and Innovation - CC Technolgies, USA

Recent innovations in fiber reinforced composite repairs have led totheir increased usage as a reinforcement for aluminum and steelstructures, though there is a lack of data regarding long term per-formance and reliability. For example, full circumference compositerepairs are being used in pipelines to reinforce weakened areas.While there has been extensive work to qualify composite repairs formechanical reinforcement, cathodically protected substrates, wet ormoist conditions, and the possible introduction of defects due tomechanical damage, abrasion, or wear affect the overall perform-ance of the product. Results of testing in these conditions will bepresented.

10:20 AMSynthesis and Electrical Properties of Cobalt-Nickel-OxideCeramic Matrix CompositesC. Kao*, H. Cheng, National Cheng Kung University, Taiwan

Synthesize the powders of various stoichiometric ratios of cobalt-nickel oxides ceramic matrix composites by chemical coprecipitation.Because chemical coprecipitation has high homogeneity, high qualityand exact stoichiometry. The characterization and electrical proper-ties of the above compounds were investigated. First, the precursorswhich were synthesized by chemical coprecipitation were analyzedwith TGA. That the precursors were transferred to complex oxidescompounds to know the probable temperature. Then XRD was usedto check the crystal type and the precursors which calcined at thetemperatures of 900C for 8, 10 and 12 hours, respectively. The parti-cle size distribution of the calcined products were measured at about0.15 ~ 0.50 μm. SEM was used to see the surface appearance of pow-ders. The electrical resistivities of cobalt-nickel oxides ceramic matrixcomposites were also measured.

Nanotechnology: Controlled Processing ofNanoparticle Structures and Composites

Nano-enabled Devices IRoom: 408Session Chair: Alex Aning, Virginia Tech

8:00 AMMicroanalytical study on piezoresistive mechanism of RuO2-particle-dispersed glass-matrix composites (Invited)M. Totokawa, DENSO Corporation, Japan; T. Tani*, Toyota TechnologicalInstitute, Japan

Piezoresistive mechanism of composite thick-films based on RuO2particles and glass matrix were investigated by chemical and electricalanalyses. The piezoresistive properties were insensitive to the RuO2specification such as particle size and surface area but the sensitivityobviously changes according to the composition of the matrix glass.

The chemical analyses on the RuO2-glass interface of the thick filmswere carried out by TEM, EDS, EELS. Furthermore, the electricalconductivity was characterized by scanning spreading resistance mi-croscopy (SSRM) and tunneling-AFM (TUNA). It was confirmedthat the binding state of the RuO2 at the interface of glass and the dif-fusion of ruthenium into the glass were different according to theglass composition. These results suggest that the piezoresistive effectis related to a change in the electrical conductivity of the interfacialreaction layer caused by the diffusion of ruthenium into glass.

8:40 AMElectrical Ceramics: Functional at Fifty (and Fewer) Nanometers(Invited)G. L. Brennecka*, J. S. Wheeler, C. M. Parish, B. A. Tuttle, A. Gin, SandiaNational Labs, USA; J. G. Ekerdt, University of Texas at Austin, USA

Continued miniaturization requires increasingly-integratednanoscale electronic components and presents challenges related tofabrication, patterning and performance. With proper control of pro-cessing, nanoscale components can exhibit electrical properties thatrival those of their bulk counterparts. This talk will focus on our re-cent work on the solution-based fabrication of functional nanoscaleelectronic components with dimensions at and below 50nm, includ-ing multilayer capacitors with capacitance densities approaching1μF/mm2, as well as discrete nanopatterned ferroelectrics and otherelectronic oxides. The increasing importance of controlling bothphase and interface development in nanoscale electrical ceramics willbe discussed in terms of traditional structure-processing-property re-lationships. Sandia is a multiprogram laboratory operated by SandiaCorporation, a Lockheed Martin Company, for the United States De-partment of Energy’s National Nuclear Security Administrationunder contract DE-AC04-94AL85000.

9:20 AMDevelopment of Nanoscale Magneto-Rheological (nMR)Suspensions: Effect of Particle Size on Flow and ThermalCharacteristics through MicrochannelsK. Sinha*, Alfred University, USA; B. Kavlicoglu, Y. Liu, Advanced Materialsand Devices Inc., USA; O. A. Graeve, Alfred University, USA

The development of nano-magnetorheological (nMR) suspensionsfor microfluidic application has progressed in two stages: (1) the syn-thesis of Fe-based nanopowders, and (2) the incorporation of suchpowders into a carrier fluid viz. ethylene glycol (0.1-1.0 vol%) andgrease (20-80 wt%) for enhanced heat transfer and microvalve appli-cations, respectively. In this study, the co-precipitation and sono-chemical processes were optimized to achieve a scalable technique forproducing nMR suspensions. X-ray and SEM/TEM results showedthe particles are comprised of the iron bcc phase with primary particlesizes <50 nm.The effect of reduced particle sizes (10-100) nm of Fe onthe magneto-rheology, flow and heat transfer capabilities of the nMRsuspensions were studied. Initial results have shown promising levelsof shear yield stress (2-10 kPa) of nMR suspensions with pressuredriven microchannel flow and thermal conductivity enhancement.

10:00 AMLow-Temperature Electrical Power Generation EmployingNanoscale Fluorite-Structured Oxide Electrolytes (Invited)S. Kim*, H. Park, U. Anselmi-Tamburini, University of California, USA; M.Martin, RWTH Aachen University, Germany; Z. A. Munir, University ofCalifornia, USA

Conventional solid oxide fuel cells (SOFCs), require high operationtemperatures (800 - 1000°C), a condition that presents technologi-cal and economic challenges. In this contribution, we report un-precedented observations of electrical power generation at tempera-tures as low as room temperature using highly dense nanostructureddoped zirconia (ZrO2) and ceria (CeO2) ceramics with the grainsize below 20 nm as electrolytes. This behavior is observed onlywhen the material is nanostructured. Open circuit electromotive

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 255

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania256

force (emf) and closed circuit currents were measured from waterconcentration cells, indicating proton conduction within the nanos-tructured oxides. The protonic conductivity in such electolytes willbe also discussed as a function of the grain size and the dopant con-centration. These results show that with optimization, viable powergeneration using water concentration cells at room temperature is apossible goal.

10:40 AMA new architecture of vertically aligned carbon nanotube film on aflexible materialS. Chang*, T. Chen, T. Tsai, National Tsing-Hua University, Taiwan; K. Hsieh,National Taiwan University, Taiwan; N. Tai, National Tsing-Hua University,Taiwan; H. Chen, National Taiwan University, Taiwan

Vertically aligned carbon nanotube films were grown on two-dimen-sionally periodical polystyrene (PS) nanosphere arrays and thentransplanted onto thermal plastic materials by microwave irradiation.With this new architecture, the excellent adhesion between the CNTsand polymer substrate and good conductivity of CNT film makes itan effectively flexible conducting material. The periodic uprising sur-face of the CNT film could be utilized as a field emitter with lowscreen effect. The field enhanced factor (β) of transplanted CNT filmwith periodic surface was triple larger than the transplanted CNTfilm with flat surface. Moreover, the periodically metallic nanobowlarray on top of the CNTs shows the effect of a photonic crystal at spe-cific wavelength of visible light. This structure formed on transparentand flexible substrates can provide a promising potential for more ex-tensive applications.

11:00 AMRole of Lattice Vibrations in a Nanoscale Electronic Device(Invited)K. Kral*, Inst. Phys. ASCR, v.v.i., Czech Republic

The electronic multiple scattering on LO phonons in quantum dotsleads not only to the fast electronic energy relaxation [1,2] in thesenanostructures, but also to the effect of the upconversion of elec-tronic level occupation in quantum dots [1]. This effect is likely toplay a role also in the open nanostructures like those of a quantumdot connected to two electrodes. We demonstrate the influence of theelectron-phonon scattering. We are going to show that in an asym-metric nanodevice one can meet e.g. an effect of a potential step gen-eration between the two electric contacts of such a device. The rela-tion of the present theoretical results to some existing measurementsof current-voltage characteristics of nanodevices will be discussed.

11:20 AMStructural and Functional Nanocomposites with HierarchicalStructures in 1-D, 2-D, and 3-D (Invited)N. P. Padture*, The Ohio State University, USA

AAdvanced nanocomposites are technology-enabling in both func-tional and structural applications. In the area of structural materials,colloidal processing, hierarchical structure, and properties ofAl2O3/single-wall carbon nanotubes (SWNTs) nanocomposites arediscussed. These nanocomposites have a 3-D network of 2-D matscomprising 1-D SWNTs, which result in unusual indentation andhigh-temperature creep properties. In the area of functional materi-als, synthesis, structure, device fabrication, and properties of 1-Dnanocomposites (nanowires) of noble metals and oxides (SnO2,TiO2, Fe2O3, NiO, BaTiO3) are discussed. These heterojunctionnanowires allow direct measurement of functional properties (elec-trical, chemical sensing, ferroelectric, piezoelectric, magnetoresis-tance) of individual oxide nanoparticles with high quality “end-on”metal contacts. These engineered nanowires could also become mul-tifunctional nanocomponents in the “bottom up” nanoelectronics ofthe future.

Nanotechnology: Nanotechnology for PowerGeneration

Nanotechnology for Power Generation IIRoom: 409Session Chairs: Gary Pickrell, Virginia Polytechnic Institute andState University; Navin Manjooran, Siemens AG, Energy

8:00 AMSensitivity of a porous clad optical fiber with varying porestructuresB. L. Scott*, C. Ma, G. Pickrell, A. Wang, Virginia Polytechnic Institute andState University, USA

An optical fiber gas sensor with a porous cladding derived from aspinodally phase separated glass was evaluated for its ability to sensegasses as a function of changes in the pore morphology. Sensitivity ofthe sensing capabilities of the fiber was tested as a function of thepore structure in the cladding region. The pore structure can influ-ence the detection of gas through the diffusion rate of the gas into thefiber and extent of the evanescent field into the porous cladding re-gion. The fibers were processed to change the pore size distribution,average pore size, pore volume, and surface area of the porouscladding. Fibers were then evaluated for response time, gas concen-tration detection limit, and the time to return to normal transmissionlevels. The effect of these factors on the optical fibers performancewill be detailed and the relationship will be shown.

8:20 AMMiniaturized Chemical Sensors by Functional Integration ofNanomaterials with Highly Sensitive Photonic Devices (Invited)H. Xiao*, T. Wei, J. Montoya, Y. Li, Missouri University of Science andTechnology, USA; J. Zhang, J. Dong, University of Cincinnati, USA

Many nanomaterials exhibit unique properties that may change dra-matically as a result of the material-chemical interactions at theatomic or molecular level. When integrated with an appropriate de-vice, these unique nanoproperties can be harvested to create highperformance nano-chemical sensors for power generation applica-tions. This talk summarizes our recent work in developing chemicalsensors through functional integration of nanomaterials with variousphotonic devices. The nanomaterials to be discussed includenanocrystalline solid oxides for high temperature gas sensing andnanoporous zeolites for detection of organics in both gas and liquidphases. The sensor platforms include the inline fiber extrinsic Fabry-Perot interferometer, thermal long period fiber grating, phase tunablelong period fiber grating, and surface enhanced Raman scatteringsensor. The representative applications of these sensors will also bediscussed.

9:00 AMSynthesis of Sb2S3 via Ultrasound as a Potential PhotosensibleMaterial in Nanocrystalline Solar CellsJ. Estevane*, E. M. Sanchez Cervantes, U.A.N.L., Mexico

Sb2S3 was synthesized in order to study its potential use inNanocrystalline Solar Cells. Sb2S3 was synthesized by an ultrasounddevice of 70W and 42kHz. UV-Vis spectroscopy analysis was done onthe synthesized samples showing spectra reported for Sb2S3 in bulksize. It was also possible to synthesize Sb2S3 particles around 35-40nm in diameter. Sb2S3 particles that seemingly show quantumconfinement properties were produced as it could be analyzed byUV-Vis spectroscopy suggesting a much more smaller size (i.e. Quan-tum dots) than that of the bulk, this was also corroborated by SEM,AFM and XRD analysis. These results open a window for Sb2S3 as apotential efficiency enhancer material in Nanocrystalline Solar Cellssuch as an organic colorant substituent material in a Grätzel configu-ration Solar Cell.

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 256

Th

urs

day

AM

www.matscitech.org 257

9:20 AMMesoporous hydrous manganese dioxide nanowall arrays withlarge lithium-ion energy storage capacitiesD. Liu*, University of Washington, USA; P. Xiao, Chongqing University,China; Q. Zhang, B. Garcia, C. Cao, University of Washington, USA

Mesoporous nanowall arrays of hydrous manganese dioxide MnO2were deposited on cathodic substrates by the potentiostatic method.The deposition was induced by a change of local pH change resultingfrom electrolysis of H2O. SEM study revealed that the nanowall ar-rays were homogeneous across the entire substrate of top thicknessesthat varied from 50 to 100 nm with identical depth. The Lithium-ionintercalation properties of such nanowall arrays were studied. Themesoporous nanowall arrays of hydrous manganese dioxide exhib-ited an initial capacity of 276 mAh/g, 258 mAh/g and 243 mAh/g fordifferent deposition thicknesses of less than 300 nm, around 500 nmand more than 1 μm. The greatly enhanced lithium-ion intercalationcapacity and excellent cyclic stability are ascribed to the large activesurface area of the nanowall arrays, a short facile diffusion path forlithium ions and the mesoporous nature of MnO2 nanowall arrays.

10:00 AMThe modeling of electromagnetic wave propagation of nano-structured fibers for sensor applicationsN. T. Pfeiffenberger*, G. Pickrell, Virginia Tech, USA

The purpose of this study is to demonstrate how the modeling ofelectromagnetic wave propagation of nano-structured fibers can beused to study the modal characteristics for sensor applications with-out the actual creation of the fiber. The fiber optic structures testedwere created using the Comsol Multiphysics software package. Theresults of this study found that Comsol Multiphysics is a very usefultool for new fiber designs and compositions. The refractive indexes ofa fiber were panned from a standard Silica glass (n=1.46) to the re-fractive index of air (n=1.0) in order to check the robustness of thevarious fiber arrangements. The conclusions of this study show thatwith certain fiber arrangements the light will be confined in eachmode that is present in the fiber. When the two refractive indexes ofthe fiber approach one another, the light will no longer be confined tothe core and losses will occur.

10:20 AMNovel Organic-Inorganic Hybrid Solar Cells Based on TitaniaNanotube Arrays and Metallo-organic/Polymer BlendsT. Jiang*, N. P. Padture, The Ohio State University, USA

Fabrication, structure, properties, and performance of novel organic-inorganic hybrid solar cells based on titania nanotube arrays and met-allo-organic/polymer blends are presented. Ordered arrays of amor-phous nanotubes are formed on indium-tin-oxide (ITO)-coated glasssubstrates using the anodization method, and they are subsequentlycrystallized to rutile titania. The nanotube dimensions are carefullytuned considering the exciton diffusion lengths, for improved effi-ciency. Hole-conducting polymers are blended with light-harvestingmetallo-organic complexes with broad absorption spectra for efficientcapture of the solar spectrum. These blends are impregnated into thetitania nanotube arrays, while providing electrodes, to create the solarcells. The structure of these solar cells is discussed together with the ef-fect of the structure on the cell properties and performance.

10:40 AMThermopower measurement of nano/microwiresS. Annamalai*, I. L. Pegg, B. Dutta, The Catholic University of America, USA

PbTe is a prospective material for thermoelectric power generationbecause of its relatively high thermopower efficiency at temperaturesaround 700 K. Several groups have recently reported spectacular in-creases of thermopower efficiency in PbTe nanostructures as com-pared to their bulk values. However, determination of thermopowerin 1-D nano/microstructures is an unresolved problem. The

nano/microwires were co-drawn in a conventional optical fiber draw-tower with a glass-cladding such that the diameter of the wires variedbetween 100 to < 1 μm. Such glass-clad fibers were etched at bothends to attach the exposed fibers to the hot and cold junctions of theexperimental setup with silver paste. Alternatively, the entire glass-cladding was etched off such that absolutely bare PbTe nano/mi-crowires were produced. Such wires, on alumina substrate were usedfor thermopower measurements. A detailed experimental procedurefor thermopower measurement of nano/microwires is presented.

Processing & Product Manufacturing: Joiningof Advanced and Specialty Materials X

Repair of Critical StructuresRoom: 410Session Chairs: Leijun Li, Utah State University; Boian Alexandrov,The Ohio State University

8:00 AMGradient Material Analysis by Digital Image CorrelationR. Grylls*, Optomec Inc., USA; T. Lienert, Los Alamos National Laboratory,USA; D. Keicher, Optomec Inc., USA

Laser Deposition of metals has found increasing application in repairand rapid manufacturing. This additive approach can be used to rap-idly create novel chemistries and microstructures. Here we describethe use of the Laser Engineered Net Shaping (LENS®) process tomake gradients of chemistry between titanium alloys, and then theuse of Digital Image Correlation (DIC) to understand the mechanicalproperties of the resulting chemistry gradients. By loading two differ-ent alloys in each powder feeder, the LENS system was able to adjustthe ratio of powders fed into the process in real time, and thus make agradient in chemistry from one alloy to the other. The DIC techniquewas then able to measure mechanical properties at discrete pointsalong the gradient. By then analyzing the chemistry and microstruc-ture along the failed tensile bar, the microstructure/property relation-ships of the grade between the two alloys were quickly analyzed. Theuse of this technique in other alloy systems will also be discussed.

8:20 AMDirect Metal Deposition: Manufacture, Repair and Restoration ofComplex Gas Turbine ComponentsJ. DSouza, B. Dutta*, J. Mazumder, The POM Group Inc., USA

With the ever increasing metal prices search for metal fabricationprocesses with near net shape finish has intensified significantly in re-cent years. This is more true for the aerospace and medical industry,where usage of expensive metals/alloys, such as Ti, Ni and Co base al-loys have multiplied several times. Direct Metal Deposition (DMD) isa Laser Aided Manufacturing (LAM) technique commercialized byThe POM Group Inc. which is used in repair and restoration of highperformance nickel and cobalt superalloys in the Aerospace, Defenceand Powergen industry. DMD provides a promising solution for hardto weld gas turbine components which are manufactured from direc-tionally solidified(DS) or single crystal (SX) alloys. Examples of suchcomponents are gas turbine blades and stator vanes segments. DMDcan also be used in providing OEM solutions such as welding of Z-notches in new gas turbine blades.

8:40 AMThermomechanical Simulation of Repair Procedure for Cr3Steel RollsB. Chen, Y. Huang*, K. Lu, X. Wang, Wuhan University of Technology, China;L. Li, Utah State University, USA

Alloy Cr3 is a recently developed support-roll material for steel mills.The weldability of this alloy has not been fully understood. By meansof welding experiments and Gleeble thermomechanical simulation,the influence of preheating temperature, cooling rate, and carbon

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 257

Th

ursd

ay AM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania258

content on weldability of Cr3 is studied. The mechanisms that corre-late the process parameters and the weld cracking tendency are inves-tigated. The results clarified the relationship between cooling rate andthe resultant microstructure, weld shrinkage, and residual stresses. Itis found that the control of the cooling rate of the deposit is the pre-ferred and effective method for the best repair quality for the crack-sensitive roller material.

9:00 AMFeasibility Study of the Repair of Aluminum Components byVariable Polarity GTAW CladdingR. Sarrafi*, D. Lin, R. Kovacevic, Southern Methodist University, USA

With the increasing application of light-weight structures, there is aneed to develop reliable methods for the repair of high-value Al com-ponents. In the repair of these alloys by welding processes, the con-cerns are the defects formed within buildups, the soundness of bondbetween the buildups and base metal, and the degradation of me-chanical properties of the original part in HAZ. This paper focuses onthe optimization of variable polarity GTAW process to achieve highquality of repairing Al 6061 by using Al 4043 as a filler alloy. Evalua-tion of cladded plates showed that no major defect formed withinbeads over a relatively wide range of parameters. However, experi-ments showed that the heat input should be optimized to obtain (1)sound bonding of beads and substrate, (2)stable cladding process,and (3)minimum damage to the structure of the part. In order to en-sure the soundness of bonding as well as the process steadiness, theheat input can not be decreased below the optimum level.

9:20 AMVibration-Assisted Laser Powder DepositionE. Foroozmehr*, D. Lin, R. Sarrafi, R. Kovacevic, Southern MethodistUniversity, USA

In this paper, a feasibility study of the effect of the applied controlledvibration during Laser Powder Deposition (LPD) on the microstruc-ture and mechanical properties of the buildups is performed. A de-vice is designed and manufactured to vibrate a substrate with a fre-quency range from 0 to 180 Hz to build up parts of the size 5x15x5mm by LPD from H13 steel. Both lateral and vertical vibration hasbeen examined. The results of this experiment show that the vibra-tion can change the microstructure of the part that contributes to lessvariation in the hardness throughout the cross-section of thebuildups based on the micro-hardness test. It is believed that the vi-bration causes a disturbance in dendrite growth leading to breakingdendrite columns. Therefore, the dendrites become approximately 25percent shorter with some random direction of formation in compar-ison to the case of without vibration. On the other hand, the vibrationreduces the size and the amount of pores for about 30 percent.

10:00 AMPulsed Laser Repair of a DS SuperalloyL. Li*, A. Deceuster, M. Mahapatra, V. Y. Zhang, Utah State University, USA

GTD-111 directionally solidified nickel based superalloy was repairedusing pulsed Nd:YAG laser powder deposition (PLPD). With opti-mized processes parameters, crack-free, multiple-layer deposits wereachieved for tip repair (top-down orientation) of GTD-111 bucketswith RENÉ 80 and IN625 filler metals. Crack-free single-layer de-posits were achieved for transverse and parallel orientations on GTD-111 buckets with RENÉ 80 filler. With the same deposition parame-ters, parallel orientation repair with RENÉ 80 filler was found toresult in less cracking than the transverse orientation repair.

10:20 AMNovel Joining and Repair of Aerospace MaterialsJ. P. Forsdike*, M. R. Bache, Swansea University, United Kingdom; S. J.Tuppen, Rolls-Royce plc, United Kingdom

Joining techniques based on local heating could offer aerospace man-ufacturers high-integrity components with reduced life-cycle costs.

The current paper will detail a comprehensive study of a novel solid-state, resistance bonding technique, applied to the β-stabilised alloyTi-6246 incorporating same-alloy powder interlayers. Microstruc-tural characterisation of the bonds is supplemented by hardness andcompositional traverses. Together with statistical analysis of bondlineporosity levels these have been employed as a means of ranking per-formance. Alpha-case formation at high temperature was circum-vented using high vacuum or inert-gas shielding and limited trialswith powders of various mean particle sizes have been performed tomaximise powder packing density. The integrity of any bonds mustultimately be demonstrated under mechanical loading. In this respectthe data and associated fractography from a preliminary matrix ofmonotonic tension and fatigue testing will be presented.

10:40 AMInfluence of Marble Particle Size in Flux Coating on Performanceof D600R ElectrodeB. Chen, F. Han, Wuhan University of Technology, China; Y. Huang*,Sinosteel Xingtai Machinery & Mill Roll Co, China; K. Lu, Y. Liu, WuhanUniversity of Technology, China; L. Li, Utah State University, USA

Conventional micron-scale marble in the flux coating of D600R, ahardfacing surfacing electrode, was replaced by marble of nanoscalesizes for possible enhanced electrode characteristics. The micron-scalemarble was substituted at a proportion of 25% with nanoscale marbleparticles with size ranges of 70~90nm, 100~130nm, ~430nm. An arccharacteristics analyzer was used to measure the welding current, arcvoltage, and short-circuiting characteristics of the electrode under vari-ous welding conditions. Mechanical properties of the weld deposit werecharacterized. The results show that the smaller marble particle sizes inthe flux coating produce a lower short-circuiting voltage, lower short-circuiting current, and a shorter short-circuiting time. The nanoscalemarble particles in flux coating produced greater metal deposition effi-ciency, as well as increased hardness and wear resistance of the deposit.

Processing & Product Manufacturing:Processing, Properties and Performance ofComposite Materials

Polymer Matrix Composites IRoom: 412Session Chair: Srinath Viswanathan, University of Alabama

8:00 AMWhispering Gallery Mode Micro-Optical Sensors: NewOpportunities for Developing Smart Composite Materials(Invited)V. Otugen*, T. Ioppolo, Southern Methodist University, USA

Whispering gallery modes (WGM) of dielectric micro-spheres can ex-hibit extremely high optical quality factors leading to resonances withvery narrow line widths. Due to this optical characteristic, several WGM-based micro-sensor applications have recently been proposed includingthose in chemical, biological and mechanical sensing areas. In the me-chanical sensing area, feasibility of force/strain, acceleration, pressureand temperature sensors have been demonstrated. In this sensor tech-nology, the microspheres of dielectric materials (silica or polymeric ma-terials) are excited by coupling light from optical fibers. The fibers serveas the input output conduit for the sensors carrying light from a tunablediode laser. The presentation will describe the WGM optical phenome-non in spheres and the feasibility of developing WGM-based fiber andparticle reinforced composites into smart materials will be discussed.

8:40 AMProcessing and Properties of Syntactic FoamsN. Gupta*, Polytechnic University, USA

Syntactic foams are hollow particle filled composites. The importanceof these lightweight materials in industrial applications is rapidly in-

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 258

Th

urs

day

PM

www.matscitech.org 259

creasing because they can lead to significant reduction in structuralweight, result in saving of energy in transportation and use, and canbe tailored for specific properties. The processing techniques, proper-ties, and applications of syntactic foams are discussed in this paper.Use of industrial waste materials such as fly ash hollow particles insynthesizing syntactic foams presents possibilities for making envi-ronmental friendly composites. Such possibilities are also discussedin terms of their effect on the cost and on the energy saving. The newpossibilities exist in designing these materials for shock resistant andhighly damping components. Additionally, the recent advances in-clude developing functionally graded and smart syntactic foams.These possibilities have long term impacts on the applications oflightweight materials in industrial applications.

9:00 AMEnvironmental Degradation of Carbon Fiber ReinforcedComposites by Boiling WaterD. Jeevan Kumar*, A. K. Singh, R. P. Singh, Oklahoma State University, USA

Carbon fiber composites degrade due to leaching of the matrixwhen exposed to high moisture environments. Degrading thecomposite in a boiling water environment would accelerate theleaching process, thus leading to a rapid degradation in the me-chanical properties of the composite. Carbon fiber epoxy com-posites, 8 layered zero degree and ninety degree plies, were fabri-cated and boiled in water for 24, 48, 96 and 192 hours. Theflexural modulus of the 192 hours degraded zero degree andninety degree composite specimens was found to be ∼15% and∼30% lesser than their corresponding virgin samples. In thispaper an effort is also made to develop a kinetic model for the dif-fusion process.

9:20 AMMorphology and Interactions in Nanostructured EVA/OrganoclayMaterialsM. Valera-Zaragoza, Universidad del Papaloapan, Mexico; E. Ramirez-Vargas,Centro de Investigación en Química Aplicada, Mexico; F. J. Medellín-Rodríguez, CIEP-FCQ, UASLP, Mexico; L. Rivas-Vázquez*, R. Suárez-Orduña, J. Hernandez-Torres, Universidad del Papaloapan, Mexico

A study of the incorporation of organically modified silicate layers ona copolymer of ethylene-vinyl acetate (EVA) by melt blending processis presented. The morphology observed by TEM confirmed the for-mation of nanostructured layers oriented in direction of melt flow.The polar character of vinyl acetate of the copolymer allowed favor-able interactions with the OH– chemical species of the silicate, lo-cated throughout each layer. In consequence, the interlayer spacingwas increased. A major formation of intercalated layers and a partialformation of totally separated or exfoliated layers were observed, re-sulting in intercalated-exfoliated morphology. The nanostructuringof the polymer/clay binary system directly was related to the charac-teristics of the groups linked to quaternary ammonium in the organicmodifier. The concentration, the number of long chains, and the po-larity of the organic groups had influence on the polymer-layer inter-actions and consequently also in the exfoliation grade.

10:00 AMHigh Performance COPVS for In-Space Storage of High PressureCryogenic Fuels (Invited)J. Schneider*, C. Hastings, M. Dyess, J. Wang, Mississippi State University, USA

Polymeric composite overwrapped pressure vessels (COPVs) pro-vide an attractive material system to support developing commerciallaunch business and alternate fuel ventures. However to be able todesign with these materials, the mechanical behavior of the materi-als must be understood with regards to processing, performance,damage tolerance, and environment. For the storage of cryogenicpropellants, it is important to evaluate the materials performance

and impact damage resistance at cryogenic temperatures in order tominimize weight and to ensure safety and reliability. As part of thisstudy, material tests of candidate fiber and resin systems were usedas the basis for the selection of the material combinations for evalu-ation in a COPV at cryogenic conditions. This comprehensive ap-proach has also been expanded to address issues with impact dam-age tolerance and material degradation due to environmentalfactors.

10:40 AMA Study on Applicability of Phenolic Fiber Reinforced Compositefor Sterntube Bearing of ShipY. So*, Y. Ahn, D. Kim, Y. Yoon, J. Youn, Hyundai Heavy Industries, Co., Ltd,South Korea

This study was performed to evaluate applicability of phenolic fiberreinforced composite to sterntube bearing which is expected tochange from asbestos to asbestos-free material. As a result of mechan-ical test, compressive strength shows 4 times in comparison withmaximum allowable compressive stress. FE analysis for strength as-sessment shows that maximum radial stress was 70% of maximumallowable working pressure. From the result of wear test, a level ofthickness reduction under lubricant cut-off condition is allowable incomparison with that of the asbestos material. Based on the results ofthis study, sterntube bearing made by phenolic fiber reinforced com-posite was actually applied to shipbuilding.

11:00 AMExperimental Study on Tensile and Flexural Behavior of GlassVinyl Ester Composites with and without Graphite Fillers and FEAR. Vajram*, S. K. Venkatachar, S. Murthylal, Sri Jayachamarajendra College ofEngineering, India

Polymer composites are being widely used as structural componentsbecause of the mechanical load-carrying capacity and the wear lifewhich determine their acceptability in industrial applications. In thisstudy the incorporation of Graphite fillers on Mechanical behavior ofGlass-Vinyl ester (G-V) composites has been investigated. The com-posites are assessed by using J.J. Lloyd UTM. The tests are conductedas per ASTM standards. From the experimental investigation, it isfound that the tensile and flexural strength of G-V composites in-creased with increasing the Graphite content. Also simulation of bothtensile and flexural properties of GV composites with and withoutGraphite fillers has been carried out to validate the experimental re-sults. The fractured surfaces of G-V composites are observed usingScanning Electron Microscope (SEM) to reveal the results.

Nanotechnology: Controlled Processing ofNanoparticle Structures and Composites

Nano-enabled Devices IIRoom: 408Session Chair: Tom Hinklin, Ceramatec

1:00 PMGas Sensor Array Devices Based on Nanostructured Metal OxidesM. A. Andio*, E. Beach, P. A. Morris, Ohio State University, USA

The objective of this study is to develop metal oxide sensor arraydevices using nanostructured metal oxides fabricated by deposit-ing the particles on a substrate using a specialized ink jet printingunit. Synthesis of metal oxide nanoparticles, microspheres, andnanoflowers was performed to study the effect of particle size andmicrostructure on electrical resistivity under specific environ-ments. The nanoparticles that were deposited and formed anopen microstructure had greater sensitivity to reducing and oxi-dizing gases than nanostructured metal oxides which agglomer-ated and formed secondary particles. The particle size and surface

001_271.MST_Abstract.4th 9/3/08 3:09 PM Page 259

Th

ursd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania260

area effects on sensitivity varied for different n-type and p-typemetal oxides. Doping of titania with niobium was also performedwhich lowered the overall resistivity of the system. Particle size,surface area, and microstructure of the thin film of metal oxideson the substrate are important to the overall performance of thesensor.

1:20 PMNanowire enhanced TiO2 particles as a platform for gas sensingB. Dinan*, M. Andio, P. Morris, S. Akbar, The Ohio State University, USA

Due to their enhanced properties nanoparticles/nanostructureshave been widely researched. One of these enhanced properties, in-creased surface area, is of particular importance in gas sensing ap-plications. To this end, we have been developing a surface modifica-tion process to thermally grow nanowires on submicron sizedtitanium dioxide (TiO2) particles for use as a platform for nextgeneration sensor technologies. By utilizing a metal catalyst in a hy-drogen/nitrogen atmosphere a process was developed by whichnanowires can be thermally grown on submicron TiO2 particles.The nanowire enhanced particles showed increased surface area,low aggregation, and good sensitivity when used as a platform forgas sensing. A sensor based on the nanowire enhanced particles al-lows for greater sensitivity to select gases than previous technolo-gies based on either TiO2 nanoparticles without nanostructures orthin films.

1:40 PMHybrid Organic / Inorganic Nanostructured Solar Cells (Invited)D. C. Olson*, National Renewable Energy Laboratory, USA

Nanostructured oxide semiconductor / conjugated polymer com-posites are promising systems for use in low cost organic photo-voltaic devices. These hybrid devices take advantage of the highelectron mobilities found in metal oxide semiconductors, while re-taining the solution-based processing available to organic semi-conductor devices. ZnO nanorod arrays are grown at low-temper-ature from solution and are subsequently infiltrated withpoly(3-hexylthiophene) (P3HT). We study the effects of nanorodarray morphology and growth chemistry, as well as processingconditions used to infiltrate P3HT into the ZnO nanorod arrays.We also examine the effect of surface treatments and modificationof ZnO prior to polymer infiltration in order to enhance electrontransfer efficiency and maintain polymer crystallinity at theZnO/P3HT heterojunctions. Finally, these results are correlatedwith device data to observe the effects of ZnO nanorod morphol-ogy, interfacial treatments, and the infiltration process on the de-vice performance.

2:20 PMApplication of hierarchically-structured ZnO aggregate films indye-sensitized solar cells (Invited)Q. Zhang, S. Jenekhe, G. Cao*, University of Washington, USA

Hierarchically-structured ZnO colloidal dispersion was synthesized andits films were used as photoelectrodes in dye-sensitized solar cells(DSSC). Such ZnO aggregate films retained the desired large surface areafor dye adsorption and introduced light scattering within the electrode,and thus increased the light harvest. The extent of aggregation, averagesize and size distribution of the aggregates were controlled by the pro-cessing conditions. Their influences on the power conversion efficiency(PCE) of DSSC have been studied. The results demonstrated that PCEincreases with increased size of aggregates and decreases drastically withdeterioration of aggregates. It was also found that poly-dispersed aggre-gate photoelectrodes offer much higher PCE than mono-sized aggregatephotoelectrodes, probably due to better packing and/or more efficientlight scattering. A PCE of 5.8% has been obtained using such hierarchi-cally structured ZnO aggregate photoelectrodes sensitized by N3 dye.

Electronic & Magnetic Materials: Fabrication,Microstructures and Interfacial Properties ofMultifunctional Oxide Thin Films

Microstructure and Dielectric Properties of Oxide FilmsRoom: 315Session Chairs: Brady Gibbons, Oregon State University; MarkLosego, North Carolina State University

2:00 PMPhase Transition Studies in Multiferroic BiFeO3 thin films usingRaman Spectroscopy (Invited)R. S. Katiyar*, M. K. Singh, R. Palai, University of Puerto , USA; J. F. Scott,University of Cambridge , United Kingdom

Eepitaxial BiFeO3(BFO) thin films were grown on STO (111) by em-ploying pulsed laser deposition (PLD) method. Raman spectra ofBFO were studied in the temperature range of 77K – 1250K. We ob-served phonon anomalies near TN that are due to combined effect ofchange in magnetic ordering and octahedral tilting in BFO thin films.Three sharp A1 Raman modes at 136, 162, and 212 cm-1 showedanomalous changes in frequencies, line widths and integrated intensi-ties close to the magnetic phase transition (TN). The sign and magni-tude of such anomalous behavior appear to be an experimental evi-dence of the perturbation in antiferromagnetic ordering coupledwith the octahedral tilting revealing strong spin-phonon interactionsaround TN. The spin phonon coupling arising from the stabilizationenergy required to bring FeO6 octahedra to a particular structuralconfiguration. Above ferroelectric phase transition (Tc), we observedinsulator – metal transition at higher temperature.

2:40 PMEnhancement of Ferroelectric Properties of BiFeO3 Thin Films byDomain and Strain Engineering (Invited)C. Eom*, University of Wisconsin-Madison, USA

We have demonstrated significant enhancement of ferroelectric proper-ties of epitaxial (001) BiFeO3 thin films by domain and strain engineer-ing. BiFeO3 on miscut (001) SrTiO3 substrates have two-variant stripedomains and show high remanent polarization and low leakage currentdensity. We also demonstrated a strong tunability of remanent polariza-tion of (001) epitaxial BiFeO3 thin films and free standing membranes.Thermodynamic analysis reveals that a strain-induced polarization ro-tation mechanism is responsible for the large change in the out-of-plane polarization with biaxial strain while the spontaneous polariza-tion itself remains almost constant. Fatigue-free switching behavior upto 1010 cycles was observed for BiFeO3 membranes with Pt top elec-trodes. This work has been done in collaboration with H. W. Jang, S. H.Beak, D. Ortiz, C. M. Folkman, Y. H. Chu, J. X. Zhang, V. Vaithyanathan,Y. B. Chen, X. Q. Pan, D. G. Schlom, L. Q. Chen, and R. Ramesh.

3:40 PMPolarization, Domain Structures, and Switching in EpitaxialBiFeO3 Thin Films (Invited)J. Zhang, S. Choudhury, Y. Li, Penn State University, USA; Y. Chu, F.Zavaliche, M. Cruz, P. Shafer, University of California, USA; H. Jang, S. Baek,D. Ortiz, C. Folkman, R. Das, University of Wisconsin, USA; V.Vaithyanathan, Penn State University, USA; Y. Chen, University of Michigan,USA; Q. Jia, Los Alamos National Laboratory, USA; X. Pan, University ofMichigan, USA; D. Schlom, Penn State University, USA; C. Eom, University ofWisconsin, USA; R. Ramesh, University of Michigan, USA; L. Chen*, PennState University, USA

BiFeO3 is perhaps the most studied single-phase multiferroics whichis simultaneously ferroelectric and antiferromagnetic at room tem-perature. This presentation will provide a brief overview of recent ad-vances in our fundamental understanding of domain structures andferroelectric properties of epitaxial BiFeO3 thin films. In particular,

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 260

Th

urs

day

PM

www.matscitech.org 261

we will discuss our recent computational predictions and experimen-tal measurements of strain and orientation dependencies of polariza-tion and domain structures. It is shown that the remanent polariza-tion of (001)-oriented BiFeO3 thin films shows a strongstrain-dependence while the spontaneous polarization itself remainsalmost constant. It is demonstrated that the domain structures andswitching mechanisms of epitaxial BiFeO3 thin films could be effec-tively controlled through strain engineering. Our ability to controlthe domain structures and switching is important for exploring themagnetoelectric coupling phenomenon in BiFeO3 films.

4:20 PMComposite-like Structure in the Epitaxial Relaxor FerroelectricBa(Zr,Ti)O3 Thin Films on (001) MgO SubstrateJ. He*, J. Jiang, E. Meletis, The University of Texas at Arlington, USA; C.Chen, A. Bhalla, University of Texas at San Antonio, USA

The BaZrxTi1-xO3 (BZT) materials are relaxor ferroelectrics havinghigh tenability and low loss and show great promise for turnable mi-crowave applications. In this work, we report the fabrication and mi-crostructure of the epitaxial BZT films grown on the (001) MgO sub-strates using PLD. Cross-section TEM shows that the film consists oftwo layers: a continuous layer near the interface region and a nanopillarlayer near the surface region. Both continuous and nanopillar layers areepitaxially grown as observed from the cross-section TEM. However,plan-view TEM of the film shows two type domains in the nanopillarlayer, among which one type domain is epitaxially grown on the con-tinuous layer. The two type domains are rotated 35 degree with respectto each other along the [110] axis. The details regarding the domainstructures and their influence on the dielectric properties are discussed.

Electronic & Magnetic Materials:Ferroelectrics and Multiferroics

Piezoelectric MaterialsRoom: 318Session Chairs: Geoff Brennecka, Sandia National Laboratories;Shashank Priya, Virginia Tech

2:00 PMVibration Damping of High-Chromium Ferromagnetic SteelS. Bhujang Mutt*, M. Kumbeeshwar, G. Bhujang Mutt, East Point College ofEngineering and TEchnology, India

The aim of the present work is to study the effect of annealing on thevibration damping capacity of high-chromium (16%) ferromagneticsteel. The alloys were prepared from raw materials of 99.9% puritymelted in a high frequency induction furnace under high vacuum. Thesamples were heat-treated in vacuum at various temperatures (800 to1200C) for 1 hour followed by slow cooling (120C/h). The invertedtorsional pendulum method was used to evaluate the vibration damp-ing capacity. A water-based magneto-fluid was used to analyze mag-netic domain morphology of the alloy using optical microscopy. Theresults indicated that the vibration damping capacity of the alloys is in-fluenced by annealing and there exists a critical annealing temperatureafter 1000C. The damping capacity increases quickly below the criticaltemperature since the magnetic domains move more easily. Above thecritical temperature the damping capacity decreases due to the largersize of the magnetic domains leading to decrease in domain wall area.

2:20 PMEffect of CoFe2O4 Coercivity by High Energy Ball MillY. P. Cardona*, R. Perez, University of Puerto Rico in Mayaguez, USA; J. Silva,A. Rossa, P. Vargas, O. Uwakweh, University of Puerto Rico, USA

The effect of high energy ball milling on precast cobalt ferrite(CoFe2O4) leads to particle size and grain size reduction coupled withboth strain and coercitvity changes. Particle size reduction from 70.46nm to a minimum value of 10 nm was achieved for a minimum of 60

minutes ball milling. The strain induced on the milled materialsreached a maximum of 0.006 after 3 hours of milling which remainedunchanged with subsequent milling for up to 10 hours of continuousmilling. Maximum coercivity of 0.29 T corresponding to 1 hour ballmilling was observed, while continued ball milling led to coercivity re-duction to 0.097 T for a particle size of 9.46 nm corresponding to astrain of 0.0063. Totality of the results demonstrates that coercivity en-hancement was not achieved with continuous particle size reduction.

Electronic & Magnetic Materials: LowTemperature Processing for Integration ofMicroelectronics Devices

Advanced System IntegrationRoom: 319Session Chair: Jun Akedo, Natl. Inst. of Advanced Industrial Science& Tech.

2:00 PMAerosol Deposition Technology for Microelectronics PackagingApplications (Invited)Y. Imanaka*, H. Amada, Fujitsu Laboratories Ltd., Japan; J. Akedo, NationalInstitute of Advanced Industrial Science and Technology, Japan

Aerosol Deposition (ASD) is the promising technology for the ad-vanced microelectronics packaging which makes it possible to simul-taneously obtain miniaturization, high performances and cost reduc-tion in RF wireless communication products. Embedded passive to aprinted wiring board is the promising solution. We proposed a resinbuilt-up circuit board embedding the ceramic film with several pas-sive functions for the RF modules. We have already produced the pro-totype of the embedded capacitor formed on a FR-4, by depositingthe BaTiO3 film at room temperature using ASD. We confirmed thatthe capacitance density of 300 nF/cm2 could be obtained on the resinsubstrate. In this study, we examined the correlation between the di-electric properties the microstructure, and crystal structure ofBaTiO3 ASD film. We also investigated the reliability of the ASD filmunder high temperature, high humidity, thermal cycle condition andbias DC voltage. We suggest the additional solution using ASD.

2:40 PMTunable Ferroelectric Thin-Film Technology Compatible withLTCC Process for Integrated RF Modules (Invited)T. Suzuki*, F. Taniguchi, K. Kawamura, Y. Mizuno, H. Kishi, Taiyo Yuden Co.,Ltd., Japan

With increasing demands for downsized, low-cost RF modules applica-ble to next-generation wireless systems, the LTCC-based integration ofpassive components has been attracting much attention and the em-bedding of ferroelectric materials is desired to integrate decoupling ca-pacitors. The electrical dielectric tuning capability of the ferroelectricmaterial provides a new solution for future communication systemsand has been intensively studied, especially as a thin-film capacitor formon silicon and sapphire substrates for RF tunable devices. In this study,we discuss the applicability of ferroelectric thin films toward RF tunableapplications and a novel thin-film process using single nano-sized crys-talline particles is proposed for low-temperature sintering compatiblewith LTCC technology. The films are fabricated by spin-coating well-dispersed BaTiO3 slurry and then sintered. The films consist of highlydensified columnar grains, showing high permittivity and tunability.

3:20 PMFerroelectric/piezoelectric devices for System-in-Package (Invited)T. Chakraborty*, R. E. Miles, A. Laister, C. James, M. Khan, T. P. Comyn, S. J.Milne, University of Leeds, United Kingdom

System-in-Package (SiP) technology is in the vanguard of the advanceof electronic systems towards ever higher frequencies and circuit den-sities. Integration of ferroelectric/piezoelectric materials, for circuit

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 261

Th

ursd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania262

elements like filters, tuners and antennae, will add even more func-tionality, compactness and cost reduction. In Leeds we are developingan RF adaptive antenna/transceiver module based on these materialswhich will include steerable antennae, tuneable filters and MEMSswitches, all integrated onto a polymer substrate. Thin and thick filmsof lead zirconium titanate, barium strontium titanate and lead stron-tium titanate are under investigation for such applications. Thispaper will investigate circuit geometries, and electrical properties thatrequired of these functional materials for their successful integrationinto SiP technology. It will also review laser transfer processing, whichis one approach to overcome problems of integrating ferroelectricfilms on temperature-sensitive substrates, such as polymers.

4:00 PMAerosol Deposition technique as an alternative method in MLCCsfabrication at room temperature (Invited)D. Popovici*, J. Park, J. Akedo, Natl. Inst. of Advanced Industrial Science andTechnology (AIST), Japan

Fabrication of ceramics as active elements in circuit components ischallenging because of today’s tendencies of miniaturization and in-creased functionality shown by electronic manufacturers. Ceramicsusually requires high temperatures for sintering and this makes diffi-cult to integrate them in dense 3D systems that contain low meltingpoint materials, or to prevent unwanted chemical reactions, interdif-fusion, shrinkage and/or alteration of the electrical properties ofcomponents already present on the fabrication board. Aerosol Depo-sition (AD) method is a relatively new deposition technique devel-oped to meet the requirements imposed by the current tendencies. ByAD, polycrystalline thick films can be formed from ceramic powdersat room temperature. The advantages and challenges associated withAD are highlighted and AD integration in multi-layered capacitor(MLCCs) fabrication is presented. MLCCs with capacitance densityof 15nF/mm2 were fabricated with voltage breakdown of 80V.

Electronic & Magnetic Materials: PerovskiteOxides: Films, Nanostructures, Properties,and Applications

Perovskite Oxides - Superconducting FilmsRoom: 316Session Chairs: Timothy Haugan, U.S. Air Force ResearchLaboratory; Parans Paranthaman, Oak Ridge National Laboratory

2:00 PMSuperconductivity and Thermoelectricity at the Interface ofPerovskite Oxides (Invited)Q. Li*, Brookhaven National Lab, USA

The pioneering discovery of the electron gas at the interface betweentwo insulating perovskite oxides LaAlO_3 (LAO) and SrTiO_3 (STO)has generated an impressive amount of experimental and theoreticalwork in part because the complex ionic structure and particular in-teractions found at such an interface are expected to promote novelelectronic phase. In this talk, I will report our research into the inter-face induced superconductivity and thermoelectric behavior, fromsynthesis to structural/property characterization.

2:40 PMMicrostructural and Pinning Properties of YBa2Cu3O7-δδ ThinFilms Doped with Magnetic NanoparticlesJ. Wang*, J. Yoon, D. G. Naugle, H. Wang, Texas A&M University, USA

In this research, we conducted a systematic study on the microstruc-tural and physical properties of the YBa2Cu3O7-δ (YBCO) thin filmsdoped with magnetic nanoparticles. We incorporated different mag-netic nanoparticles with various doping concentrations either bylaser ablation of a composite target through premixing YBCO and

dopant powders, or by alternative growth of YBCO and dopant tar-gets. We conducted a detailed microstructural characterization on allthese samples by X-ray diffraction (XRD), scanning electron mi-croscopy (SEM), and cross-sectional transmission electron mi-croscopy (TEM). The critical current densities at both self-field andin-field (Jcsf and Jcin-field (H//c)) and the critical transition temper-ature (Tc) of these films and a pure YBCO sample were measured bya Superconducting Quantum Interference Device (SQUID). The pin-ning properties of these doped films were explored at different tem-peratures and correlated with their microstructural characteristics.

3:00 PMLaMnO3: Excellent Cap Layer for IBAD-MgO Template BasedHigh Performance Second Generation Superconducting WiresM. P. Paranthaman*, T. Aytug, O. Polat, Y. Zhang, A. Goyal, Oak RidgeNational Laboratory, USA; Y. Chen, X. Xiong, V. Selvamanickam, SuperPower,Inc, USA

A single LaMnO3 (LMO) has been identified as an excellent cap layerfor ion-beam assisted deposition (IBAD) MgO template because ofits excellent compatibility with IBAD-MgO and as well as withREBa2Cu3O7-δ (REBCO). Using metal-organic chemical vapor dep-osition (MOCVD), REBCO films with a critical current density ofover 4 MA/cm2 in self-field at 77 K for a film thickness of 0.7 μm hasbeen achieved on rf-sputtered LaMnO3-buffered IBAD MgO sub-strates in short lengths. This corresponds to an Ic of 280 A/cm-width.In addition, LMO process has been scaled up to over kilometerlengths with excellent and uniform texture. This promises a route forfabricating IBAD-MgO based second generation YBCO tapes withLMO cap layers in pilot-scale production. This work was supportedby the Department of Energy, and Office of Electricity Delivery andEnergy Reliability (OE).

3:40 PMEnhancing Critical Currents of YBCO Superconductors withNanoparticle AdditionsT. Haugan*, M. J. Mullins, E. Brewster, J. Reichart, J. F. Baca, J. Bulmer, P.Barnes, U.S. Air Force Research Laboratory, USA; H. Wang, Texas A&M Univ,USA; M. Sumption, The Ohio State Univ, USA

On-going studies to increase the critical current density (Jc) ofYBa2Cu3O7-δ (YBCO) superconductors with nanoparticle additionswill be described. Methods to increase both intragranular and inter-granular properties were tested. Different oxides nanoparticles werestudied including Y2BaCuO5, Y2O3, and other insulating phases withlattice mismatches from 0% to 20%, and also magnetic phases includ-ing SrRuO3,Y3Fe5Ox and others. Nanoparticles were incorporated bylaser deposition of (M/YBCO)N multilayer and (YBCO1-xMx) sin-gle-target films with M additions of 0.5-20 Vol%. New results with themagnetic nanoparticle additions indicate Tc transitions are minimallyaffected, and Jc(H) increases > 50% were achieved for the entire rangeof H = 0-9T and temperatures ≤ 77K. Using insulating nanoparticles,grain boundary Jc increased 2x to 20x compared to YBCO for [001]and [010] tilts from 4° to 36°. Microstructural and superconductingproperties will be summarized, including SEM and TEM analysis.

4:00 PMExploring the interfacial defects in nanostructured YBa2Cu3O7-δδthin filmsH. Wang*, J. Wang, J. Yoon, Texas A & M University, USA; S. R. Foltyn, Q. Jia,H. Zhou, B. Maiorov, L. Civale, Los Alamos National Laboratory, USA; J.MacManus-Driscoll, University of Cambridge, United Kingdom; T. J.Haugan, F. J. Baca, C. V. Varanasi, P. N. Barnes, Air Force ResearchLaboratory, USA

Recently, several successful nanoparticle-doping and nanolayeringapproaches for overcoming the YBCO field-dependence have beendemonstrated. The pinning effects of these nanoparticles andnanolayers are believed to be that the nanoparticles and/or the inter-facial defects or the strain field created by these nanoparticles pin the

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 262

Th

urs

day

PM

www.matscitech.org 263

flux lines effectively. We conducted a detailed microstructural studyon several selected nanostructured YBCO thin films processed usingpremixed targets, sectioned targets, and alternating growth of twotargets. All samples were deposited by a pulsed laser deposition tech-nique. The doping materials include CeO2, BaZrO3, Y2O3, BaSnO3and others. The interfacial defects, including misfit dislocations, sec-ondary phases and stacking faults in different systems were studiedand compared using cross-section transmission electron microscopy(TEM), high resolution TEM and STEM imaging.

4:20 PMElectronic Structure and XANES/ELNES Spectral Calculation inYBa2Cu3O7 Superconductor (Invited)W. Ching*, P. Rulis, University of Missouri-Kansas City, USA

The YBa2Cu3O7 (YBCO) is the most well known and important crystalwith a perovskite structure. The electronic structure of the YBCO super-conductor has been investigated by many researchers and they play animportant role in the construction of many competing and sometimesconflicting models for superconductivity mechanism. XANES/ELNESspectroscopy is an important tool for materials characterization. Wepresent the results of a systematic calculation of the XANES/ELNESspectra of all elements in this crystal using the first-principles supercellOLCAO method. These results include the Y-K, Y-L3, Ba-K, Ba-L3, Cu-K, Cu-L3, and O-K edges at all crystallographic nonequivalent sites (O1,O2, O3, O4, Y, Ba, Cu1 and Cu2). The calculated results are comparedwith the available experimental data in the literature. Extension of thesecalculations to realistic models with O vacancy and grain boundarieswith impurity doping and their implications will be discussed.

Environmental & Energy Issues: GreenTechnologies for Materials Manufacturingand Processing

Waste Minimization and RecyclingRoom: 323Session Chairs: Elizabeth Hoffman, Savannah River NationalLaboratory; Carol Jantzen, Savannah River National Laboratory

2:00 PMGeopolymers for Hazardous Wastes and Thermal TreatmentResidues (Invited)C. M. Jantzen*, P. R. Burket, A. R. Jurgensen, C. L. Crawford, Savannah RiverNational Laboratory, USA

The use of geopolymers for waste containment entails nano-scale desta-bilization of common clays followed by alkali activation of the clay toform an amorphous inorganic aluminosilicate polymer. Geopolymerapplication to the stabilization of Environmental Protection Agency(EPA) Resource Conservation and Recovery Act (RCRA) metals was ex-amined. In addition, the use of geopolymers as binders for hazardous/ra-dioactive thermal treatment residues such as those produced during Flu-idized Bed Steam Reforming (FBSR), calcination, and/or incinerationwas studied. The geopolymers had measured densities of 1.66-1.94 g/ccand compressive strengths of 4400-7700 psi. The RCRA stabilizedgeopolymers met the TCLP treatment standards at less than the Univer-sal Treatment Standards (UTS) limits even though the geopolymer con-tained 60X the UTS hazardous element concentrations. The low watercontent of the geopolymers should inhibit H2 generation from radiolysisand geopolymers should be superior waste forms compared to cements.

2:40 PMRevaluation of Tank Chemistry Control Requirements forCorrosion ProtectionE. Hoffman*, P. Zapp, B. Wiersma, K. Subramanian, Savannah River NationalLaboratory, USA

Large underground carbon steel tanks are used to store high level ra-dioactive waste at the DOE Savannah River Site (SRS). Controls on

the tank solution chemistry are in place to prevent the initiation andpropagation of pitting and stress corrosion cracking. These controlsare based upon a series of experiments performed using simulatedsolutions on materials used for construction of the tanks. An experi-mental program was undertaken to investigate reducing the mini-mum molar nitrite concentration required to confidently inhibit pit-ting. Electrochemical and coupon testing are being performed withinthe framework of the statistical test matrix to determine the mini-mum necessary inhibitor concentrations, and develop a quantitativeto predict pitting propensity. By lowering the minimum amount ofnitrite necessary to prevent corrosion, less inhibitor will be added tothe tanks, thereby conserving tank volume.

3:00 PMRinsewater Reduction CalculatorW. J. Fullen*, J. Unangst, Boeing, USA

Regulatory and cost drivers have increased the focus on rinsewaterreduction at the Boeing Plant in Auburn, Washington. The firststep in making reductions is to determine the amount of rinsewa-ter required for a given process, taking into account requirementsdriven by health and safety, applicable specifications and partquality. This can be accomplished with the Rinsewater ReductionCalculator (Calculator), which is a Microsoft® Access database thatmodels single, double counter-current, and triple counter-currentrinse tanks. Implementing timer settings generated with the Cal-culator in place of subjective practices has reduced rinsewaterusage by more than 50%. Application of the Calculator is dis-cussed, and the tool is available for download from the BoeingCompany web site.

3:40 PMMetallurgical Recovery of Metals from Electronic WastesL. Zhang*, Missouri Univ. Sci. Tech., USA

Waste electric and electronic equipment, or electronic waste, has beentaken into consideration not only by the government but also by thepublic due to their hazardous material contents. The major economicdriver for recycling of electronic waste is from the recovery of pre-cious metals and the reuse of energy from the combustion of plastics.The state of the art in recovery of precious metals from electronicwaste by pyrometallurgical processing, hydrometallurgical process-ing, and biometallurgical processing are highlighted in the paper. Re-cent research on recovery of energy from PC waste gives an examplefor using of plastics in this waste stream. It indicates that thermal pro-cessing provides a feasible approach for recovery of energy from elec-tronic waste if a comprehensive emission control system is installed.In the last decade, attentions have been removed from pyrometallur-gical process to hydrometallurgical process for recovery of metalsfrom electronic waste.

4:00 PMAnion Exchange Property of As(III), As(V), Se(IV), Cr(VI) andB(III) with Hydrotalcite-like CompoundsJ. Shibata*, N. Murayama, S. Matsumoto, Kansai University, Japan

Hydrotalcite-like compounds (HT) is one of the inorganic anion ex-changers and have a layered structure of metal complex hydroxides.In this study, the anion exchange properties of various toxic anionscomposed of As(III), As(V), Se(IV), Cr(VI) and B(III) were investi-gated by using the hydrotalcite-like compounds and its calcinationproducts. Various toxic metal ions can be removed from aqueous so-lution by the anion exchange reaction in the pH region where toxicmetal ions exist as the anionic species like AsO2-, HAsO42-, CrO42-, SeO32- etc. When the hydrotalcite-like compounds containingCrO42- after an anion exchange operation were calcined at 773K, itis found that the anionic species in hydrotalcite-like compounds canbe immobilized. It is possible to use the hydrotalcite-like com-pounds as an excellent water treatment agent for toxic anionicspecies.

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 263

Th

ursd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania264

4:20 PMPilot Testing of a Green, No-Waste, Process to Maximize Valuefrom Hot Aluminum DrossO. R. Singleton*, Singleton Technology, Inc., USA

The Dross-Spin process was tested on a 150-kg dross scale in cable,extrusion, sheet & foil, and reclamation plants. Hot dross wasprocessed at the furnace (or remotely) with an immediate, pri-mary-recovery of metal. Primary recovery varied from 20% to80% of and with available metal content depending on now estab-lished furnace and operating conditions. Product remelt skim was4% or less. Extraneous bath, steel or refractory posed no problems.The residue (cooled and friable) was crushed, ground, andscreened. The only pollution was dust from residue processing.Residue +1⁄ 4-inch yielded about 40% RSI on induction remelt. Allthe process residuals were used to make foamed cement. An opti-mum value-recovery practice was found based on material bal-ances and economics. At commercial scale, the suspended spinnerwould be a modification of an air-motor-driven spinner long usedin tonnage galvanizing operations. Spin speeds would be less than200-rpm.

4:40 PMNew Applications for Recycled Metallic Matrix CompositesN. Cantres*, J. Vázquez, M. Suárez, University of Puerto Rico, USA

This project studied the feasibility of producing Recycled AluminumMatrix Composites (RAMCs) by adding AlB2 particles. The recycledalloy was obtained from beverage can tabs mixtures were preparedcontaining 2 and 5wt.% B. Another mixture containing similar levelsof boron was fabricated using a virgin commercial 5182 alloy. Mi-croindentation proved that the average microhardness values weresimilar between recycled samples and new Al matrix composite sam-ples. Also particle size analysis ranging from 10-11μm were compara-ble in both materials. Differential temperature analysis proved thatboth have similar melting and solidifying temperature around630oC. The tests performed proved that both materials regarding thepercent of AlB2 have similar mechanical properties and suggest thepossibility of creating a new series of RAMCs using recycled beveragecan alloys. The next step is to produce RAMC’s via High Energy BallMilling (HEBM) as an alternate processing route with 100% recycledmaterial.

Fundamentals & Characterization: CeramicSurfaces, Grain Boundaries and Interfaces

Interface Structure and Properties IIRoom: 301Session Chairs: Adham Hashibon, University of Karlsruhe; ShenDillon, Carnegie Mellon University

2:00 PMThe T-Stress and Fracture in Ceramics: How Can We Utilize it?(Invited)I. Reimanis*, J. Dorsey, J. R. Berger, Colorado School of Mines, USA

The prediction of crack paths in brittle materials containing inter-faces, for example, polycrystalline ceramics, composites, or joints, canbe quite challenging, but is essential in developing fracture criteria.Crack tip stress fields in brittle materials are typically described by thewell-known Williams’ expansion, but only the first terms of the ex-pansion, those which contain the stress intensity factors, are utilizedin most cases. It has been recognized for about 40 years that the sec-ond term in this expansion, commonly referred to as the T-stress,may be correlated to crack path stability. Recent studies have revealedthat the value and sign of the T-stress may be used to predict thecrack path and crack path stability for fracture in ceramics with com-plex stress distributions, for example, when interfaces and gradientsare present. This paper examines the utility of the T-stress for the pre-

diction of crack path, and crack path stability for fracture problems inceramics with interfaces.

2:40 PMGrain Boundary Atomic Structures, Segregation site andProperties in Oxide Ceramics (Invited)Y. Ikuhara*, The University of Tokyo, Japan

Grain boundaries in ceramics play an important role on the variousproperties. It has been known that the addition of small amount ofdopants strongly improve the mechanical and functional propertiesin polycrystalline ceramics. Z-contrast images obtained by scan-ning transmission electron microscopy (STEM) is powerful tech-nique to experimentally determine the location of the dopants seg-regated at grain boundaries. STEM technique is thus especially wellsuited for understanding the role of heavy impurities in grainboundaries composed of much lighter ions. In this study, the well-defined grain boundaries in Al2O3 and ZnO bicrystals doped withY and Pr were observed by using high-angle annular dark fieldscanning transmission electron microscopy (HAADF-STEM). Cs-correctd-STEM was used for the present experiments (Cs-correctorattached JEM-2100F, JEOL Co. Ltd.), and the HAADF detector withan inner angle greater than 60 mrad. was used with an probe sizeabout 0.1nm.

3:20 PMBoron Enrichment at TiN Interfaces (Invited)C. Scheu*, University of Leoben, Austria; D. Hochauer, J. Wagner, MaterialsCenter Leoben Forschung GmbH, Austria; V. Srot, Max-Planck-Institute forMetal Reseach , Germany; N. Grobert, K. Jurkschat, Oxford University,United Kingdom; M. Kathrein, CERATIZIT Austria GmbH, Austria; C.Mitterer, University of Leoben, Austria

Nanocrystalline coatings based on the Ti-B-N system are promisingcandidates for wear-resistant applications where high hardness andgood oxidation resistance are required. In the present work, Ti-B-Nfilms with varying boron contents (0.3 - 35 at.%) were producedusing thermal chemical vapor deposition. Advanced transmissionelectron microscopy (TEM) techniques revealed that the structure ofthe nanocrystalline coatings changes from columnar to fine-grainedas a function of B content. The crystal size of the TiN grains de-creased from 200 nm to approximately 20 nm leading to an increasein hardness. The combination of high-resolution TEM, energy-filter-ing TEM, and electron energy-loss spectroscopy were employed inorder to indentify the boron position. Surprisingly, boron segregatedpreferentially to TiN twin boundaries. It is important to note thatmost of the other interface configurations in samples containing 0.3at.% boron are free of boron.

3:40 PMDetermining the Chemistry and Phase Relationships in Al-Si-Cu-Mg Nanoparticles Using In-Situ TEM (Invited)S. K. Eswaramoorthy, J. M. Howe*, G. Muralidharan, University ofVirginia, USA

This presentation describes in-situ hot-stage transmission electronmicroscope (TEM) experiments performed on hypereutectic Al-Si-Cu-Mg nanoparticles to investigate the chemistry and phase relation-ships of the three main phases: solid Si, solid Al and liquid Al-Si, as afunction of temperature. It was found that solid Al is completely wetby the liquid and cannot nucleate heterogeneously on Si or thenanoparticle oxide, while Si usually nucleates heterogeneously on theoxide. It was possible to estimate the interfacial energies of the vari-ous phases based on their wetting behavior. Because large undercool-ings are required to homogeneously nucleate solid Al, it was possibleto directly determine the metastable liquidus and solidus phaseboundaries in the undercooled liquid using energy-dispersive X-rayspectroscopy, in addition to the compositions across the solid Si-liq-

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 264

Th

urs

day

PM

www.matscitech.org 265

uid interface. This research was supported by NSF under GrantDMR-0554792.

4:00 PMGrain Boundary Complexions in Creep Resistant and CreepCompliant AluminaS. K. Behera*, M. P. Harmer, Lehigh University, USA

Polycrystalline microstructural development and associated thermo-physical properties are influenced by dopants and impurities segre-gated to grain boundaries. It is being gradually recognized that grainboundaries are best treated as interface “phases” (complexions) thatdictate kinetics of the interfacial diffusional processes. A previous casestudy in alumina revealed boundary complexions of varying structuralorder that showed corresponding changes in diffusion processes whenboundary mobility was used as a metric. The main purpose of thisstudy is to characterize (by EXAFS and HRTEM) the grain boundarycomplexions associated with the most creep resistant alumina (Y andLa doped) as well as the most creep compliant alumina (Cu-Ti doped).

4:20 PMRole of Silicon in Abnormal Grain Growth Development in Fe-3%SiK. S. Rao*, C. J. Kiely, Lehigh University, USA; A. D. Rollett, Carnegie MellonUniversity, USA; M. P. Harmer, Lehigh University, USA

Grain oriented silicon steel (Fe-3%Si) sheets have high anisotropydue to their very strong Goss texture, which is responsible for the re-markable magnetic properties. In the industrial production processof Fe-3%Si abnormal grain growth of Goss oriented grains occursduring final annealing at high temperatures. Even though the mecha-nisms of abnormal grain growth or secondary recrystallization in sil-icon steel have been studied for more than 50 years, there is still noclear understanding of this phenomenon. The bulk microstructureand the chemical composition of the normal and abnormal grainboundaries in silicon steel have been studied by HREM and aberra-tion corrected analytical electron microscopy. Chemical compositionprofiles across the matrix/abnormal grain boundary have been deter-mined from quantitative analysis of STEM-EDS spectra. The role ofsilicon in promoting abnormal grain growth is interpreted in terms ofa grain boundary phase (complexion) transition.

Fundamentals & Characterization: Discoveryand Optimization of Materials throughComputational Design

Mesoscale Modeling and Microstructural Evolution IIRoom: 303Session Chair: Nele Moelans, K.U.Leuven

2:00 PMEnhancing Piezoelectric and Multiferroic Responses throughPatterning: Phase-field Simulations (Invited)J. Zhang, L. Chen*, Penn State University, USA

In this presentation, we will report our recent efforts in exploring theeffect of patterning on the piezoelectric and multiferroic responses ofepitaxial thin films. We employed the phase-field approach to predict-ing the domain structures and ferroic responses of epitaxial ferroelec-tric/multiferroic islands under external fields. Examples to be dis-cussed include the piezoelectric properties of PbZr0.2Ti0.8O3ferroelectric islands and magnetoelectric coupling coefficients ofBaTiO3-CoFe2O4 nanocomposite thin films. In both cases, dramati-cally enhanced properties were obtained, and their magnitudesstrongly depend on the substrate strains and the aspect ratio of the is-lands. These results clearly demonstrate the possibility of optimizingpiezoelectric responses of ferroelectric thin films and the mangetoelec-tric coefficients of multiferroic nanocomposites through patterning.

2:40 PMPhase field modeling of alloy microstructural evolutions driven byirradiation (Invited)P. M. Bellon*, A. Badillo, R. S. Averback, University of Illinois, USA

Current phase field models for diffusion-controlled evolutions in thesolid state are based on phenomenological kinetic equations. Thelack of absolute time and space scale raises problems when applyingthese models to alloys subjected to irradiation by energetic particlessince this external forcing introduces new length scales and timescales. We propose here an approach that relies on a mixed continu-ous-discrete treatment of the evolution of chemical species and pointdefect concentrations. This approach makes it possible to take intoaccount important irradiation effects, namely the production andelimination of point defects and point defect clusters and the forcedchemical mixing. Examples of application of the model are given, inparticular for heterogeneous segregation and precipitation reactionsinduced by irradiation.

3:20 PMMultiscale Modeling of Waveform Design for Fast StableElectrodeposition (Invited)A. C. Powell*, Opennovation, USA

For a long time electrowinning and electrorefining processes formetals such as copper have used an alternating current waveform toachieve fast electrodeposition without developing roughness. Themetal deposits under a forward bias, slowly developing slight rough-ness, then polarity is briefly reversed, quickly smoothing the surface.Here a Cahn-Hilliard phase field model of electrodeposition pre-dicts the growth and shrinkage of roughness during such cyclic op-eration at short timescales and micron to millimeter lengthscales.This meso-scale model includes ohmic resistance at the interface asan approximation for Butler-Volmer charge transfer resistance atthe interface. Its implementation is based on the libMesh parallel fi-nite element library with adaptive remeshing and redistribution.This model then produces the constitutive relationship for a larger-scale longer-time simulation of overall shape change of a growingcathode.

4:00 PMRecent Additions to the Alloy Theoretic Automated ToolkitA. van de Walle*, California Institute of Technology, USA

The Alloy Theoretic Automated Toolkit (ATAT) is a softwarepackage automating the construction and the simulation of lat-tice-gas models based upon ab initio data that is aimed at generat-ing quantitative thermodynamic data for solid-state alloy systems.Recent progress in the development of this software package ispresented: (i) The inclusion of infinite-range interactions, such aselectrostatic interactions; (ii) Monte Carlo simulations with hy-brid constrained canonical and grand canonical ensembles formulticomponent multi-sublattices systems; (iii) the tensorialcluster expansion. Features (i) and (ii) are illustrated with an ap-plication to the calculation of interfacial thermodynamic proper-ties in Samarium-doped Ceria nanoscale superlattices that havebeen proposed as an efficient electrolyte for solid oxide fuel cellapplications. Feature (iii) constitutes a significant generalizationof the cluster expansion formalism that has important applica-tions for materials design and optimization, since most techno-logically-relevant properties are tensors (e.g., elastic constants, di-electric constants, phase-transformation-induced strains,permanent dielectric dipoles, piezoelectricity, etc). This newmethod generates a suitable orthogonal basis for the space of allmappings from lattice configurations to tensors. It also providessymmetry rules to determine which terms in the Tensorial ClusterExpansion are equivalent by symmetry and must therefore share acommon coefficient.

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 265

Th

ursd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania266

Fundamentals & Characterization:Performance and Growth of Bulk and ThinFilm Materials - Role of Surface and InterfacePhenomena during Growth and Processing

Role of Surfaces and InterfacesRoom: 306Session Chair: Ravindra Nuggehalli, New Jersey Institute ofTechnology

2:00 PMOvershoot Graded Layers for Defect Engineering inHeteroepitaxial Semiconductor Structures (Invited)J. F. Ocampo, E. Suarez, D. Shah, P. B. Rago, F. C. Jain, J. E. Ayers*, Universityof Connecticut, USA

Overshoot graded layers are of interest for controlling defect den-sities in heteroepitaxial semiconductor devices. We studied dislo-cation densities in ZnSySe1-y/GaAs (001) structures with over-shoot graded buffer layers. In each structure, a uniform devicelayer was grown on a graded buffer. Structural characterizationwas by high-resolution x-ray diffraction. In forward-graded struc-tures, an overshoot interface with 0.1% mismatch removed 2 x 108

cm-2 dislocations from the top layer. This indicates that disloca-tions are bent over at the overshoot interface by a Matthews andBlakeslee or half loop closure mechanism, and the average misfitsegment length was ~ 4 x 104 cm. Reverse-graded structures hadsignificantly higher (~2x) dislocation densities than forward-graded structures, due to enhanced dislocation generation in theearly stages of epitaxial growth. The inclusion of overshoot did notsignificantly affect the dislocation densities in reverse-gradedstructures.

2:40 PMMercurous Bromide Crystals for Acousto-Optic Applications(Invited)N. B. Singh*, M. Gottlieb, D. Suhre, D. Knuteson, D. Kahler, A. Berghmans, W.Brian, S. McLaughlin, M. Fitelson, J. Fusco, N. Paraskevopoulos, NorthropGrumman Corporation, ES, USA

The acousto-optic tunable filter (AOTF) -based spectral imagers havegreat potential for compact, lightweight, field portable, programma-ble, and adaptive imaging systems with no moving parts. Within theclass of mercurous halides, mercurous chloride is most developedand well characterized. The physical vapor transport growth methodwas used for growing crystals of mercurous chloride. We are using asimilar method to grow mercurous bromide, which has shown ahigher acousto-optic figure of merit. We carried out extensive experi-ments to produce good quality source materials and developed pa-rameters to optimize crystal growth and fabrication of AOTF devices.We used physical vapor transport (PVT) method to grow single crys-tals of Hg2Br2 in a two-zone transparent furnace. Large crystals weregrown and fabricated and transmission, scattering and bulk trans-parency were studied. A cm size Acousto-optic device was fabricatedby orienting the ingot by X-ray and cutting and polishing close to the<001> orientation.

3:40 PMA Novel MEMS Fabry-Perot Interferometric Pressure SensorI. Padron*, A. T. Fiory, N. M. Ravindra, New Jersey Institute of Technology, USA

A novel Fabry-Perot Interferometric Sensor (FPIS) consisting of aFabry-Perot cavity formed between two bond surfaces is proposedhere. The Fabry-Perot cavity coupled with the optical fiber will beused as the sensing element and interconnect, respectively. TheFabry-Perot cavity will be fabricated using the MEMS technologytechnique. The introduction of the center rigid body diaphragm gives

to our sensor considerable advantages compared with the currentFabry-Perot cavity base sensor.

4:00 PMAtomic, Electronic, and Defect Structure of the DynamicallyFormed Cu2O/Cu InterfacesX. Han*, L. Li, J. C. Yang, University of Pittsburgh, USA

To understand the kinetics detail of how the metal and oxygen atomsconvert to oxide, the interface structure of cross-section Cu2O/Cuwhich was dynamically formed in the initial oxidation stage (beforescale growth) has been studied. In this study, the Cu2O/Cu interfacewas formed by oxidation of 300nm (001) Cu films on STO sub-strates at P (O2) =5X10-4 torr at 350 °C where triangular-in-cross-section Cu2O islands formed with cube-on-cube orientation withrespect to the Cu film. Dual beam (DB) focused ion beam (FIB) in-strument was utilized to select an oxide island, slice through it fromcertain direction, and thin the interface. High-resolution TEM(HREM) observations revealed an interfacial zone (~2 nm thick).Initial electron energy-loss spectrum (EELS) investigations revealedan interfacial zone of 2~3 nm thickness where the oxidation statestransited from Cu0 to Cu+1, suggestive of the exsistence ofmetastable Cu oxides.

4:20 PMAlteration of Substrate Compliance and Effects on Fracture ofThin Metallic FilmsM. S. Kennedy*, Clemson University, USA; J. Yeager, Washington StateUniversity, USA; I. Rook, I. Luzinov, Clemson University, USA; D. Bahr,Washington State University, USA; N. Moody, Sandia National Laboratory, USA

The responses of metallic films in flexible thin film systems to me-chanical strain are unique compared to those in semiconductors filmsystems. These metallic films can be stretched to higher strains beforefracture and cannot be described by traditional models for these sys-tems due to the influence of factors that include substrate compli-ance, strain localization and creep. Using a model system of Au/Kap-ton, the ability to measure interfacial fracture energy using bulgetesting was verified. During this test, compressive stresses wereformed along the interface and resulted in the buckling of the Aufilms. Initial results show that the fracture energies of Au/Kaptonwere 0.2 J/m2 and this energy was increased when PVP was added toform Au/PVP/Kapton. To separate the compliance alteration fromshifts in chemistry along the film substrate interface, the compliancewas also be altered by chemically modifying the Kapton substratewith the addition of 100 nm thick PGMA-co-PBMA films.

4:40 PMSolidification Behaviour of Optical material: PbCl2-AgCl SystemA. Singh*, N. Singh, G. D. Singh, T.D.Post Graduate College, India; O. P.Singh, K.N.Government College, India

The heavy metal halides such as lead halides and mercury halideshave been found to be excellent optical materials for window and op-toelectronic devices. The doping changes their properties signifi-cantly. We carried out experiments to observe the shape of solid-liq-uid interface of silver doped lead chloride to study the solutedistribution and effect of growth parameters on the quality of grownmaterial. We observed that with increasing translation rate, solid-liq-uid interface changed significantly. It got depressed and then with in-creasing growth velocity, interface breaking started. Details ofgrowth, transmission measurements and bulk transparency will bedescribed in this presentation.

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 266

Th

urs

day

PM

www.matscitech.org 267

Fundamentals & Characterization: RecentAdvances in Structural Characterization ofMaterials

Electron Microscopy and Electron Diffraction:Developments and Applications IIIRoom: 309Session Chair: Guangwen Zhou, State University of New York,Binghamton

2:00 PMIn-situ TEM Study on the FERL/FERH phase transition in Nb-DopedPb(Zr0.95Ti0.05)O3 CeramicsW. Qu*, X. Tan, Iowa State University, USA; P. Yang, Sandia NationalLaboratories, USA

The ferroelectric-to-ferroelectric phase transition between the hightemperature (FERH) and the low temperature (FERL) rhombohedralphases in a Nb-doped Pb(Zr0.95Ti0.05)O3 ceramic was investigated withTEM. Both bright field images and electron diffraction patterns weremonitored as a function of temperature as well as dc electric fields. Aspecial TEM specimen holder that permits the application of electricfield was employed for the study of electric field-induced phase tran-sition. It was found that both 1⁄ 2(011)c- and 1⁄ 2(111)c-type superlatticediffraction spots were present at room temperature. On heating, the1⁄ 2(111)c-type superlattice spots were observed to disappear at tem-peratures above the phase transition temperature. When dc electricfields were applied at room temperature, the 1⁄ 2(111)c-type superlat-tice spots vanished with increasing electric field, indicating the occur-rence of an electric field-induced FERLÇFERH phase transition.

2:20 PMThe Yield Strength Anomaly in Fe2MnAl Single CrystalsY. Liao*, I. Baker, Dartmouth College, USA

A [411]-oriented single crystal Fe55Mn19Al26 was grown using a mod-ified Bridgman technique and its mechanical behavior investigated asa function of temperature. Specimens were strained under compres-sion over the temperatures range 300-900K at a range of stained rates.A yield strength anomaly was observed in which the yield strengthpeak was ~180 MPa at 600K at a strain rate of 5×10-6 s-1, with theyield strengths ranging from 170 MPa at 300K to 70 MPa at 900K.The peak strength increases to ~300 MPa at 700K at a higher strainrate of 5×10-4 s-1. Microstructural analysis in the TEM showed thatthe compound adopted the L21 structure at room temperature, butthat it transformed to the B2 structure at ~900K. In the L21 state thesuperdislocations were four-fold dissociated with the outer partialsseparation being 4 nm while that of the inner partials was 15nm. Theinteraction of the gliding dislocations with the thermal anti-phaseboundaries was studied by in-situ straining. Research supported byNSF grant DMR-0505774.

2:40 PMCrystallographic and Analytical Characterization of precipitationin ferritic weld metal deposited with a Self-Sheilded arc weldingprocessB. Narayanan*, L. Kovarik, The Ohio State University, USA; M. Quintana, TheLincoln Electric Company, USA; M. J. Mills, The Ohio State University, USA

Ferritic weld metal deposited with a self-shielded arc welding processis intentionally alloyed with aluminum, magnesium, titanium andzirconium for deoxidation and denitriding the weld pool. These re-sult in a complex precipitation process that has been characterizedwith electron microscopy techniques. A spinel oxide formation hasbeen determined to be critical for the nucleation of nitrides of zirco-nium and titanium and prevent the agglomeration of aluminum richoxides as well as the formation of large aluminum nitrides. The ni-tride growth on the spinel conforms to a cube on cube orientation in

spite of a large mismatch between the nitride and oxide lattice pa-rameters. High resolution transmission electron microscopy hasbeen used to characterize the interface between the oxide and nitride.The key role of titanium and zirconium on the improvement to frac-ture toughness as measured by Charpy V-Notch measurements aredetailed.

3:00 PMAnalysis of the accessibility of macroporous alumino-silicateusing 3D-TEM imagesM. Moreaud*, C. Benoit, F. Tihay, IFP-Lyon, France

Macroporous alumino-silicate are catalytic materials used in chemi-cal and petroleum industries. Their selectivity and activities are di-rectly linked to the morphology of their texture. By means of 3Dtransmission electron microscopy (3D-TEM) images, complex in-formation about the structure at the nanometric scale can be ob-tained. A segmentation method coupled with a method of extrac-tion of the volume of pores keeping intact the irregularity of thesurface are presented. Porosity and specific surface area are calcu-lated and compared with measures achieved by means of otherphysical measurement methods. An analysis of the connections be-tween the pores is presented using a pore-to-pore tortuosity mapprocessed using geodesic constrained distance propagations. It al-lows a global quantification of the connections between the pores inorder to estimate the accessibility to the catalyst for a particle of aknown size.

Iron & Steel: Steel Product Metallurgy andApplications

Microstructure Analysis Room: 330Session Chair: Craig Darragh, The Timken Company

2:00 PMMicrostructure Characteristics and CO2 Corrosion ResistanceProperties of Electrical Resistance Welded (ERW) PipeZ. Zuogui*, T. Qingchao, D. Xiaoming, L. Junliang, Baoshan Iron & Steel Co.Ltd, China

CO2 corrosion is one of important and dangerous corrosion pat-terns for the application of tubular goods in the petroleum and gasexploiting. In the present study, the CO2 corrosion resistanceproperties of ERW pipe are investigated in a simulated condition ofoil well at different temperatures using an autoclave. The resultsshow that the corrosion reaction is most seriously at 60 degree C.The corrosion products are analyzed by X-ray diffraction. Mi-crostructural characteristic of weld seam, heat affected zone andpipe body are respectively studied by SEM, EBSD and TEM. Rela-tionship between corrosion behavior and microstructure of weldpipe are discussed.

2:20 PMThe precipitation behavior of steels with niobium and copperX. Wang*, C. Shang, X. He, C. Li, University of Science and TechnologyBeijing, China

The precipitation behavior of steels with various niobium ad copperhas been investigated with the aid of SEM, TEM, and the Hardnesstest. The composition of the ε-Cu precipitates during various stageshas also been studied. And the influence of the cold deformation andcooling rate on the precipitation of the steel was also studied. The re-sults show that the cold deformation of steels before aging can accel-erate the aging precipitation process. By the combination of the colddeformation and the aging precipitation hardening the steel can ob-tain good mechanical properties. During the aging the substructurewas formed and the ultra fine microstructure was obtained.

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 267

Th

ursd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania268

2:40 PMCharacterization of low carbon bainitic microstructure by usingCs-corrected STEM/EELS and EBSDJ. Kang*, G. Gu, N. Lim, C. Park, POSTECH, South Korea

The austenite phase of low carbon steels can be transformed to vari-ous bainitic microstructures during continuous cooling process.However, the transformation characteristics of each bainitic mi-crostructure did not be fully identified because the transformationnoses of these bainitic microstructures were widely overlapped. Inpresent study, solute distributions and misorientation angle acrossphase boundaries were analyzed by using Cs-corrected STEM/EELSand 3 dimensional EBSD tomographic techniques, respectively.Granular bainite which transformed at high temperature around600C consisted of small subgrains and it contained 2nd phase con-stituents between grain and subgrain boundaries. Acicular ferritetransformation was occurred at intermediate temperature and it wascharacterized by an aggregate of randomly oriented and irregularshaped grains. Bainitic ferrite transformation was occurred under550C and it revealed uniform lathes and those lathes showed similarorientations.

3:00 PMAdvanced High Strength Steels (AHSS) with Duplex Ferrite andAustenite MicrostructuresM. C. McGrath*, S. N. Lekakh, D. C. Van Aken, V. L. Richards, MissouriUniversity of Science and Technology, USA

This paper will present preliminary work on third generation ad-vanced high strength steels with acicular ferrite and austenite mi-crostructures. Inoculation of intragranular ferrite was investigated byexploring a two stage deoxidation practice; partial deoxidation withaluminum and finishing deoxidation with titanium. According to lit-erature, the titanium oxide will coat the alumina particles and pro-vide effective nucleation sites for intragranular ferrite. A base chem-istry of 5%Mn, 1.5%Si, 0.35%C, 0.3%Mo and 0.005%B was used inthese experiments. Elevated levels of manganese and nitrogen wereused to increase the strength of the parent austenite phase and subse-quently reduce the ferrite plate thickness to a nano-scale. A mi-crostructural study as a function of cooling rate was performed usingthe Jominy end-quench test and these microstructures were com-pared to microstructures produced by austempering.

Materials & Systems: Advances in Biomedicaland Biomimetic Materials

Bioceramics IIIRoom: 333Session Chair: Samar Kalita, University of Central Florida

2:00 PMTricalcium phosphate coating on Ti using LENSM. Roy*, A. Bandyopadhyay, S. Bose, Washington State University, USA

Laser engineered net shaping (LENS) was used to coat Ti with trical-cium phosphate (TCP) ceramics to improve bone-cell materials in-teractions. During this process, the Nd:YAG laser melted the top sur-face of Ti substrate in which TCP powder was fed to create a TCP-Ticomposite layer. An increase in laser power and/or powder feed rateincreased the coating thickness. Flexural strength of the coating wasdetermined by three point bend test and was found to be > 400 MPa.Sliding wear characteristics of the coatings were determined in physi-ological body fluid at 37oC by ball on disc technique. Effects of TCPcoating on bone cell-material interactions were examined by cultur-ing osteoprecursor cells (OPC1) on the coated surface. Antibacterialactivity analysis using metallic Ag via electrodeposition showed over99% reduction against the growth of colonies of Pseudomonas aerug-inosa. The presentation will include interface microstructures, me-chanical properties and cell-materials interactions of these coatings.

2:20 PMYoung’s modulus, shear modulus and Poisson’s ratio as a functionof porosity for alumina and hydroxyapatiteF. Ren*, E. D. Case, M. J. Baumann, A. Q. Morrison, Michigan StateUniversity, USA

Elastic properties are fundamental to characterizing the stress-strainbehavior. In particular, the stiffness matrix for finite element analysisrequires the Young’s modulus and Poisson’s ratio as input data. TheYoung’s and shear modulus, however, decrease exponentially with in-creasing volume fraction porosity. Thus knowledge of the modulus-porosity relationships are critical for engineered bone tissue materialssuch as hydroxyapaptite, where porosity is essential to their biologicalfunction. We will discuss Resonant Ultrasound Spectroscopy meas-urements of the elastic moduli as a function of porosity for bothpolycrystalline hydroxyapatite and polycrystalline alumina, wherealumina serves as a “model” material.

2:40 PMChemical and Physical Modification of Calcium Aluminates foruse as a Bone Scaffold MaterialR. Palchesko*, Duquesne University, USA; K. A. McGowan, WestmorelandAdvanced Materials, USA; E. S. Gawalt, Duquesne University, USA

In this investigation of a potential bone scaffold material, the physicaland chemical properties of the hydrated calcium aluminate material(CA) are optimized to allow for increased osteoblast adhesion andproliferation. Pore sizes were varied through the casting process andmeasured by optical and scanning electron microscopy. CA with av-erage pore sizes ranging from 100 to 300 μm were tested to determinethe optimum conditions for cell attachment. 3T3 fibroblasts were in-cubated with the CA for 1, 4 and 7 days with cell viability and prolif-eration determined using a Live/Dead Assay. Cell adhesion peptides,KRSR and RGD, were attached to the surfaces via a linker system de-veloped for this scaffold. The linker system utilizes room temperaturesolution deposition of functionalized carboxylic acids for covalentpeptide attachment. The peptides allowed for improved cell adhesionand tissue growth as compared to the unmodified CA.

3:00 PMNanophase Hydroxyapatite in Biodegradable Polymer Compositesas Novel Drug-Carrying Implants for Treating Bone Diseases atTargeted SitesH. Liu*, T. J. Webster, Brown University, USA

Desirable cytocompatibility properties of nanocrystalline hydroxyap-atite (HA) were combined with the tunable degradability and de-formability of a select polymer (poly-lactide-co-glycolide, or PLGA)to optimize biological and mechanical properties for bone regenera-tion. In this study, nano-HA/PLGA composites were used as noveldrug delivery systems to treat bone diseases at targeted tissue-implantinterfaces. Specifically, a model peptide (DIF-7c) derived from bonemorphogenetic protein (BMP-7) was loaded into nano-HA/PLGAcomposites using a covalent chemical bonding method. Resultsshowed that the model peptide was successfully immobilized ontonano-HA in a greater loading efficiency using amino-silane chem-istry. Importantly, a prolonged two-phase peptide release wasachieved using nano-HA/PLGA drug delivery systems. Ceramic/poly-mer nanocomposites are promising drug-carrying implant materialsfor treating bone diseases at targeted sites.

3:40 PMMechanical Properties Modeling of Porous Calcium PhosphatesCeramicsF. Pecqueux*, N. Payraudeau, F. Tancret, J. Bouler, Université de Nantes,France

We investigate and model the influence of both macro and microporosities on mechanical properties of Biphasic Calcium Phosphate(BCP) ceramics that are thereafter used as resorbable bone substi-

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 268

Th

urs

day

PM

www.matscitech.org 269

tutes. Our BCP ceramic is a mix between hydroxyapatite and trical-cium phosphate synthesized by soft chemical hydrolysis, isostaticpressing and conventional sintering. A porogen is added to the pow-der before pressing and sublimated to create macropores in a con-trolled proportion. The sintering parameters are chosen to obtainvarious microporosities. Our mechanical properties models are tak-ing into account separately the influence of the two porosities. Com-pression and toughness tests are performed on samples covering theoverall porosities ranges and their results are compared with themodels. The agreement between the modeled and tested compressivestrengths is excellent. These validated models can be useful to helpdesigning bone substitutes with improved microstructures and me-chanical properties.

4:00 PMProcessing of FGM with Five Concentric Layers by Spark PlasmaSinteringT. Watanabe*, Nihon University , Japan; H. Izui, Y. Fukase, M. Okano, NIhonUniversity, Japan

Functionally gradient materials (FGM) with five concentric layerswere fabricated by spark plasma sintering (SPS). The FGMs werecomposed of hydroxyapatite (HA), β-tricalcium phosphate (β-TCP),and titanium hydride. Ingredients of FGM were radially changedform Ti-rich layer to HA-rich or β-TCP-rich layer. The FGM can in-corporate incompatible functions of good biocompatibility and highstrength. The titanium hydride was discharged hydrogen during sin-tering, and promotes the sintering of powders. β-TCP improved thebiocompatibility of FGMs. The objective of the present study is toclarify the effects of composition of the layer on the bending strengthand crack generation behavior. The residual stress generated at the in-fluences during sintering. The residual stress induced in the FGM wascalculated by FEM. The crack-free FGMs with five concentric layerswere successfully fabricated by SPS. The composition of each layerwill be discussed.

Materials & Systems: Enabling SurfaceCoating Systems: Science and Technology

Multifunctional Coatings IIRoom: 335Session Chair: Pravansu Mohanty, University of Michigan

2:00 PMThermal Shock Resistance of a Functionally Graded Coating withPeriodic Edge CracksZ. Jin*, Y. Feng, University of Maine, USA

This paper presents a thermo-fracture mechanics model to investigatethe effects of crack density and thermal property gradients on the thermalshock resistance of a functionally graded coating with an array of periodicedge cracks. The critical thermal shock that causes crack propagation andthermal shock damage are determined using linear elastic fracture me-chanics. The thermal shock residual strength of the FGM as a function ofthermal shock severity and crack density (crack spacing) is subsequentlyevaluated. Numerical calculations are carried out for two FGM materials,i.e., Al2O3/Si3N4 and TiC/SiC FGMs, to illustrate the effects of crackdensity and material gradation on the thermal shock strength behavior ofFGMs. It is found that a higher crack density (lower crack spacing) to-gether with appropriately graded material properties significantly en-hances the residual strength of the thermally shocked FGMs.

2:20 PMLaser Surface Modification of 2024 Al Alloy for High ThermalConductivityV. K. Balla*, S. Bose, A. Bandyopadhyay, Washington State University, USA

Surface modification has been used to improve wear resistance, cor-rosion resistance and thermal barrier properties of metals. However,

no significant attempts have been made to improve thermal conduc-tivity by surface modification. In this work, we have examined thefeasibility of enhancing thermal conductivity of 2024 aluminum alloyby depositing 80Cu-20Mo using Laser Engineered Net Shaping(LENS). Coatings of 667 ± 2.5 μm thickness with metallurgicallysound interface were formed. Results show that 87% increase in thethermal conductivity of Al 2024 alloy can be achieved by depositing80Cu-20Mo alloy. Our results show that this coating approach can beused on high modulus, low CTE metal matrix composites (MMCs) toenhance their thermal conductivity for electronic applications. More-over, since LENS is rapid prototyping technique, it can produceMMCs with engineered shapes and functional gradation in composi-tion with enhanced heat transfer capabilities.

2:40 PMNext Generation Boiler Wire DevelopmentD. J. Branagan*, A. R. Patete, B. E. Meacham, B. D. Merkle, K. M. Byrne, TheNanosteel Company, USA

A new family of iron based glass forming alloys have been developedfor elevated temperature erosion / corrosion protection of water wall,superheat and reheater exchange tubes and other surfaces in coalfired and circulatory fluidized bed (CFB), and biomass boilers. Whenthermally sprayed using the twin roll wire-arc process, the resultingcoatings are found to exhibit high coating density with excellent bondstrength. The microstructure of the coatings, due to their excellentglass forming ability is either fully amorphous or partially devitrified,depending on the specific chemistry and spray condition resulting incoatings with high hardness, high corrosion resistance, and superiorperformance in elevated temperature erosion when compared to ex-isting conventionally scaled materials. In this talk, the properties ofthe newly developed amorphous / devitrified nanocomposite coat-ings will be compared to those of other boiler coatings, other coatingapplication strategies, and bare tubes.

3:00 PMMethyl-modified Melting Gels for Hermetic Barrier CoatingsA. Jitianu*, G. G. Amatucci, L. C. Klein, Rutgers University, USA

Melting gels are organic-inorganic glasses that seal at temperatureslower than all-inorganic glasses and, unlike sol-gel glasses, are non-porous. Organically-modified silica melting gels prepared by the sol-gel method are rigid at room temperature, but soften and re-soften attemperatures in the range 100-120oC. After consolidation at around135oC, the gels no longer re-soften. Gels were prepared using methyl-triethoxysilane (MTES) and dimethyldiethoxysilane (DMDES), withcompositions between 50-50 and 75-25 mol%. Thermal gravimetricanalysis and differential scanning calorimetry were performed, alongwith FTIR and Raman spectroscopic analyses. Micro-hardness wasmeasured by Knoop indentation. A helium leak test was performedand the helium transmission rate was found to be ~8.6 cm3/day. Inaddition, 5x5 cm2 foil envelopes filled with common organic elec-trolytes were sealed with melting gel and stored for 4 weeks at 70oC.The measured weight loss after 4 weeks was less than 1%.

Biomaterial CoatingsRoom: 335Session Chair: Pravansu Mohanty, University of Michigan

3:40 PMFunctionally-graded Nanocomposite Biocompatible Coatings forOrthopedic ImplantsT. W. Scharf*, W. Tu, A. Devaraj, J. Y. Hwang, R. Banerjee, The University ofNorth Texas, USA

One of the most critical requirements of orthopedic implants is ex-cellent wear resistance and lubricity on the surface of the femoralhead (ball part of the ball-socket joint). This presentation discussesnewer generation alloys, nanocomposite coatings, and novel manu-facturing processes for customized functionally-graded orthopedic

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 269

Th

ursd

ay PM

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania270

implants. A combination of hybrid processing technologies, includ-ing laser-engineered net shaping (LENS™) for alloy development aswell as physical vapor deposition (rf/dc biased sputtering) and pulsedlaser deposition of lubricous ZnO coating will be discussed as routesto functionally-grade the surfaces of these implants. Friction andwear behavior of these coatings and composites and detailed studiesof the composition and microstructure of the composites will also bediscussed.

4:00 PMLaser Assisted Zr/ZrO2 Coating on Ti for Biomedical ApplicationsV. K. Balla*, P. DeVasConCellos, W. Xue, S. Bose, A. Bandyopadhyay,Washington State University, USA

Oxidized Zr alloys have been shown to exhibit lower friction and su-perior wear properties suggesting their use in hip and knee implants.However, conventional oxidation of Zr alloys above 500°C, in dry air,for several hours have detrimental effect on substrate properties. Inthis work, we have deposited pure Zr on Ti and then oxidized thecoating using lasers, which facilitates localized heating to elevatedtemperatures without affecting the substrate. Laser assisted oxidationresulted in fully dense, 6 μm thick ZrO2 layer on Zr, and showed sig-nificantly higher hardness. Zr coating oxidized at a laser power of 200W and 5 mm/s scan speed showed comparable in vitro biocompati-bility to that of pure Ti. The laser oxidized surface also showed excel-lent in vitro cell-materials interactions. The presentation will focuson processing of Zr/ZrO2 coatings on Ti using LENS, and coatingsmechanical, microstructural and in vitro biological characterization.

4:20 PMRF Plasma sprayed hydroxyapatite coating on TiM. Roy*, A. Bandyopadhyay, S. Bose, Washington State University, USA

Plasma sprayed hydroxyapatite (HAp) coatings are widely used in or-thopedic and dental applications. Most of these applications demandgood adhesion with the substrate and a long term stability of thecoating. To maintain long term stability, high level of crystallinity isnecessary in HAp coatings, since resorption of amorphous HAp issignificantly higher than its crystalline form. A rapid cooling of thepartially melted particles increases amorphicity in HAp coatings. Par-tially melted particles in plasma spray dissipate heat to the substrateand cool at a very high rate. Therefore most of the coating at or nearthe interface is amorphous in nature. We have studied to understandthe influence of a thermal barrier layer to improve coating crys-tallinity. XRD results show that the surfaces of the coatings are highlycrystalline with very small amounts of other phases. The presentationwill include interface microstructure, crystallinity, hardness, adhesivestrength and wear properties of the coatings.

4:40 PMZrO2 Coatings for Biomedical ApplicationsM. Contreras-García*, I. Espitia-Cabrera, R. Sosa-Rodríguez, H. OrozcoHernández, B. Bermúdez-Reyes, Universidad Michoacana de San Nicolás deHidalgo, Mexico

Recently biomaterials use has been increasing, between them, bioce-ramics can be bioinert, like alumina, zirconia and ytria partially stabi-lized zirconia; bioactive, like hydroxiapatite, with similar compositionto bone, and biodegradables like some high density polymers. A newhybrid synthesis route to obtain a bilayer zirconia coating, on 316LSS,is proposed. Using a combined deposition route, electrophoretic dep-osition (EDP) to obtain the first zirconia layer and screen printingtechnique to deposit a YPSZ second layer, in order to obtain a thickand porous coating morphology in the second layer, similar to thebone structure. Screen printing deposition is a versatil method thatnot require special conditions, is cheap and can be adapted to differ-ent sustrate forms. By this combined deposition techniques the ob-tained coatings are thicker, roughness and porous, conditions thateasily alow osteointegration. The coatings characterization by SEM,

EDS and XRD and the corrosion behavior in physiological serummedia are presented.

Processing & Product Manufacturing:Processing, Properties and Performance ofComposite Materials

Polymer Matrix Composites IIRoom: 412Session Chairs: Judy Schneider, Mississippi State University; VolkenOtugen, Southern Methodist University

2:00 PMReview: Self-Healing Composites (Invited)E. Woldesenbet*, N. Fikru, LSU and Southern University, USA

The growing interaction between biological and material sciences isleading researchers to incorporate biomimetic features into newly de-veloped materials. The study of self-healing materials is inspired bybiological systems in which damage triggers an autonomous healingresponse. The field of self-healing now involves several disciplines in-cluding biology, chemistry, mechanics and materials science and en-gineering. In the late nineties, suggestions were made that autoge-neous healing of cracks in concrete is possible with waterpermeability. However, the first report of a man-made self-healingmaterial was made in 2001 where microcapsules filled with healingagent are dispersed within an epoxy matrix that has catalyst suspen-sion. Since then, much advancement have been made in self-healingcomposite materials, all demonstrating self-healing functionality inengineering materials. Currently, new concepts are being developedin self-healing composite materials like hollow fiber and microvascu-lar network composite materials.

2:40 PMAnalysis of Sensitivity of an Encapsulated Micro-Optical Sensorfor Structural Health Monitoring in Composite MaterialsN. Nguyen, N. Gupta*, Polytechnic University, USA

Various types of fiber-optic sensors can be used in composite materi-als for structural health monitoring. Whispering gallery mode(WGM) sensors are a special class of micro-optical sensors that arecreated by optical coupling of dielectric microparticles and opticalfibers. Such sensors have potential to be used in particulate and fi-brous composites to measure stress or strain. The combination ofparticle and optical-fiber to create sensor requires encapsulatingthem in a suitable material to incorporate in the composite. The sen-sitivity of the encapsulated sensor needs to be calibrated. The presentstudy uses modeling and simulation approaches to develop theoreti-cal estimates of sensitivity of the encapsulated WGM sensors. Solidand hollow microparticles are considered for the study. Hollow mi-croparticles of the same material provide higher sensitivity because oftheir lower effective elastic modulus, providing higher strain for thesame applied force.

3:00 PMProcessing and Properties of Advanced Polymer MatrixCompositesS. L. Lewis*, R. Marvel, W. Sherwood, T. Russell, Starfire Systems, Inc., USA

Polyramics are a group of high temperature stable polymers based onsiloxane chemistry. These polymers have a potentially wide range ofapplications due to their unique properties. The polymers are stableup to 300°C, are inherently flame-retardant and have good stiffnessand strength. The polymers also have electrical properties whichmake them attractive as low-loss substrates for microelectronics ap-plications. Both fiber-reinforced (glass, carbon) and particle-filled(SiC, alumina) systems have been produced in our research facility.This presentation follows the process from the synthesis of a novelpolymer through the study of some basic properties such as curing,

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 270

Th

urs

day

PM

www.matscitech.org 271

mechanical properties and electrical properties to the manufacture ofprototype composite parts for such diverse industries as microelec-tronics, aerospace and materials synthesis.

3:40 PMEffect of Moisture Absorption on Interfacial Shear Strength ofFluorinated Epoxy Carbon Fiber CompositesC. H. Kareliya*, G. Pandey, R. P. Singh, Oklahoma State University, USA; J.Hinkley, NASA Langley Research Center, USA

Increased use of carbon fiber composites has caused a concern abouttheir long-term durability since many of these applications are exposed tomultiple environment like moisture, temperature and UV radiation.Conventional epoxy based carbon fiber composites readily absorb mois-ture. However, scientists at NASA LaRC have synthesized novel fluori-nated epoxy, which have reduced moisture absorption and hence poten-tially reduced environmental degradation. This project aims towardsstudying the effect of moisture absorption on fluorinated epoxy carbonfiber composites and their comparison with their conventional counter-parts. Microbond and single fiber fragmentation tests were performed onfluorinated and non-fluorinated epoxy based single fiber coupons beforeand after boiling water degradation. Results show that fluorinated epoxybased single fiber coupons exhibit relatively reduced degradation in inter-facial shear strength as compared to their non-fluorinated counterparts.

4:00 PMAnalysis of the Fracture Process in Epoxy Reinforced CompositesUnder Different Loading ConditionsA. A. Mazen*, El-Menia University, Egypt; M. A. Metwalli, Ain ShamsUniversity, Egypt; N. A. El-Mahallawy, The German University in Cairo, Egypt

The fracture process in epoxy composites was analyzed under differentloading conditions, i.e., tensile, compressive, and bending loads. Epoxywas reinforced with three different woven fabrics, i.e., woven glass fab-rics woven carbon fbricsm and hybrid reinforcement made of alter-nating layers of woven carbon and woven glass fabrics. The reinforce-ment volume fractions used ranged from 0 vol.% fibers(unreinforcedepoxy) to 36.8 vol.% fibers. Macroscopic and SEM (scanning electronmicroscopic) examination were used for characterization and analysisof the fracture process. Under tensile loads, it was found that un-rein-forced epoxy fractured in a completely brittle manner accompanied byfragmentation of the specimens. At low glass reinforcement volumefraction, the fracture process showed matrix-controlled behavior.Fractured started in the matrix away from the fiber bundles causingfiber overloading which lead to fiber de-bonding and fiber pull-out.

4:20 PMPerformance Analysis on Glass fiber-epoxy used for applicationsin Marine and Slurry environmentZ. E. Kennedy*, NIT Trichy, India; A. Chatterjee, SRM University, India; S.Natarajan, NIT Trichy, India; T. Mishra, SRM University, India

In any high-tech marine application, where strength, stiffness,durability, light weight, resistance to corrosion and erosion are re-

quired, epoxy resins are seen as the composites with maximumstandard of performance. The GFRP was manufactured usingHand Lay-up technique as laminates. They were tested for varioustribological properties like erosion, corrosion, and general mechan-ical properties like tensile, impact and hardness testing. Duringerosion, the wear increases with the increase in slurry concentra-tion. Also, increase in surface velocity increases the rate of wear.The specimen was tested using salt spray tester to find out if anydelamination or debonding has occurred, but no such noticeableindications were observed. SEM showed localized material removalin few areas and erosion due to plastic deformation on rest of thezones of the laminate. Hence an effort has been made so as to re-place the currently used material with GFRPs in order to gain bet-ter performance.

Late AbstractTuesday, 11:20 AMRoom 408Nanoparticle Sintering II SessionControlled Fabrication of Novel Nanocomposites via 3D Self-Assembly (Invited)A. Goyal*, Oak Ridge National Laboratory, USA

Nanocomposites comprising ordered 3D arrays of nanodots of onetype of ceramic material embedded in another ceramic matrix com-prise are expected to exhibit novel physical properties tunable by ad-justing the overall composition, concentration, feature size and spa-tial ordering of the nanodots. Applications of such nanocompositesin the areas of multiferroics, photovoltaics, solid state lighting, ultra-high density storage and high temperature superconductivity are ofinterest. We report here on a joint experimental, theoretical andcomputational study on achieving 3D ordering via 3D self-assemblyof nanodots of a complex ceramic material within another complexceramic material, such as 3D self-assembly of BaZrO3 nanodots inREBCO superconducting films. Vertically ordered arrays of BaZrO3(BZO) nanodots within REBCO films have been shown to resultfrom a simultaneous phase separation and ordering (SPSO) process.BZO and REBCO phase separate during the initial growth stage andBZO forms crystalline nanodots surrounded by REBCO epitaxial lay-ers. As the PLD deposition continues, this phase separation continuesand nucleation of the next BZO nanodot occurs at positions exactlyabove the existing BZO nanodot in the layer below. This results in theformation of vertical columns of BZO nanodots within the REBCOfilm. The origin of the size selection of the nanodot formation as wellas the influence of growth conditions on size, interface structure, andnanodot spacing and ordering has been determined. Experimentalresults obtained for novel nanocomposites for other applications in-volving perovskite-spinel mixtures such as CoFe2O4-BaTiO3,CoFe2O4-BiFeO3, etc. will also be presented. It is expected that self-assembled nanocomposites such as these will find application inmany areas.

001_271.MST_Abstract.4th 9/3/08 3:10 PM Page 271

Author Index

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania272

A

Aagesen, L.K. . . . . . . . . . . . . . . . . . . . . . . . . . . .247Abd Aziz, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Abd-Elwahab, S. . . . . . . . . . . . . . . . . . . . . . . . . .101Abdizade, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Abdollah-zadeh, A. . . . . . . . . . . . . . . . . . . . . . . .31Abe, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Abe, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29, 87Abraham, B.M.* . . . . . . . . . . . . . . . . . . . . . . . . .245Adachi, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Adachi, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Adamo, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Adams, S.N.* . . . . . . . . . . . . . . . . . . . . . . . . . . .180Adedokun, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .78Adelakin, T.K. . . . . . . . . . . . . . . . . . . . . . . . . . .136Aden-Ali, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Adeosun, S.O.* . . . . . . . . . . . . . . . . . . . . . . . . . .136Adler, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .217Adler, S.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Advani, S.G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .55Aertsens, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Affatigato, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .128Afonso, C.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Afsar, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Agaogullari, D.* . . . . . . . . . . . . . . . . . . . . . . . . .224Agarwal, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .53, 87Agarwal, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Aghaie-khafri, M. . . . . . . . . . . . . . . . . . . . . . . . .20Agnew, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Agrawal, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115Agrawal, D. . . . . . . . . . . . . . . . . . . . . . . . . .129, 135Agrawal, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Agrawal, D.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Agrawal, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Aguirre Perales, L.Y.* . . . . . . . . . . . . . . . . . . . . .249Aguirre, M.H. . . . . . . . . . . . . . . . . . . . . . . . . . . .145Ahmed, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49Ahn, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Ahn, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Ahn, K. . . . . . . . . . . . . . . . . . . . .182, 215, 226, 246Ahn, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261Ahrens, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Ai, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Aindow, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249Akada, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61, 62Akahori, T. . . . . . . . . . . . . . . . . . . . . . . . . .123, 154Akao, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Akarapu, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Akarapu, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .255Akatov, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Akbar, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Akbar, S.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Akbar, S.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .196Akbarzadeh, A. . . . . . . . . . . . . . . . . . . . . . . . . . .106Akcora, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Akedo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .263, 264Akhtar, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Al Busaidi, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Al Hajeri, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .120Al Shalfan, W. . . . . . . . . . . . . . . . . . . . . . . . . . . .120Al Shammary, S. . . . . . . . . . . . . . . . . . . . . . . . .120Alain, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Alam, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .229

Alapati, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Alaraj, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Al-Badri, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Albert, A.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .232Albu, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218Albu, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218Alderson, K.J. . . . . . . . . . . . . . . . . . . . . . . . . . . .188Aleixo, G.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Alexander, D. . . . . . . . . . . . . . . . . . . . . . . . . . . .177Alexander, D.* . . . . . . . . . . . . . . . . . . . . . . . . . .198Alexandre, M. . . . . . . . . . . . . . . . . . . . . . . . . . .243Alexandrov, B.T.* . . . . . . . . . . . . . . . . . . . . . . . .228Alford, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Aliya, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Alizadeh, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Alizadeh, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .155Al-Jamal, K.T. . . . . . . . . . . . . . . . . . . . . . . .154, 254Al-Jamal, W.T.* . . . . . . . . . . . . . . . . . . . . .154, 254Al-Jassim, M. . . . . . . . . . . . . . . . . . . .182, 215, 246Al-Kassab, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Allan, D.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85Allan, S.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Allan, S.M.* . . . . . . . . . . . . . . . . . . . . . . . .194, 207Allazadeh, M.R.* . . . . . . . . . . . . . . . . . . . . . . . .188Allen, A.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .46, 84Allen, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Allen, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Allen, T.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Allison, J.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212Allsup, R.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .147Almer, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .244Almer, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Aloy, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Alpas, A.T. . . . . . . . . . . . . . . . . . . . . . . . . . .12, 173Alshaaer, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .208Al-Sharab, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .182Altamirano-Torres, A. . . . . . . . . . . . . . . . . . . .5, 11Alvarez, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Alvarez, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Amada, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Amancio, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .134Amarakoon, V. . . . . . . . . . . . . . . . . . . . . . . . . . .110Amarakoon, V.W. . . . . . . . . . . . . . . . . . . . . . . .102Amarandei, D. . . . . . . . . . . . . . . . . . . . . . . . . . . .22Amatucci, G.G. . . . . . . . . . . . . . . . . . . . . .140, 271Ambrosek, J.W. . . . . . . . . . . . . . . . . . . . . . . . . . . .9Amezawa, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .110Amin, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Amini, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Amoroso, J.W.* . . . . . . . . . . . . . . . . . . . . . . . . .180Amruthaluri, S. . . . . . . . . . . . . . . . . . . . . . . . . .131Amruthaluri, S.* . . . . . . . . . . . . . . . . . . . . . . . .131An, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214, 224An, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .163, 192An, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Anderoglu, O. . . . . . . . . . . . . . . . . . . . . . . . . . .111Anders, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Andersen, K.B. . . . . . . . . . . . . . . . . . . . . . . . . . .171Andersen, K.E. . . . . . . . . . . . . . . . . . . . . . . . . . .166Anderson, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .191Anderson, H.U.* . . . . . . . . . . . . . . . . . . . . . . . . .92Anderson, I.E.* . . . . . . . . . . . . . . . . . .98, 164, 226Anderson, M.H. . . . . . . . . . . . . . . . . . . . . . . . . . . .9Anderson, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . .101Anderson, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .49Andersson, A.D. . . . . . . . . . . . . . . . . . . . . . . . . .205Andersson, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .219

Andio, M. . . . . . . . . . . . . . . . . . . . . . . . . . .230, 262Andio, M.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .261Ando, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Andreola, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Andry, P.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Anguiano-Wehde, N. . . . . . . . . . . . . . . . . . . . . .82Aning, A.O. . . . . . . . . . . . . . . . . . . . . . . . . .29, 228Aning, A.O.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .200Annamalai, S.* . . . . . . . . . . . . . . . . . . . . . .226, 259Anselmi Tamburini, U. . . . . . . . . . . . . . . . . . . .219Anselmi-Tamburini, U. . . . . . . . . . . . . . . . . . . .257Antony, J.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .136Aoshima, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .141Apblett, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224Apblett, A.* . . . . . . . . . . . . . . . . . . . . . . . . .40, 173Apeagyei, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Apel, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247Arai, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Araujo, J.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Araujo, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Arbuthnot, D. . . . . . . . . . . . . . . . . . . . . . . . . . .204Arellano, I.J.* . . . . . . . . . . . . . . . . . . . . . . .4, 11, 34Arfaei, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Arin, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Armstrong, B. . . . . . . . . . . . . . . . . . . . . . . . . . . .10Aroni, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28Arribas, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Arroyave, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Arroyave, R.* . . . . . . . . . . . . . . . . . . . . . . .176, 216Arthur, W.G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Asai, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Asher, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Ashizawa, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .232Asif, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Asta, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Asta, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Asthana, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Asthana, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Ataee, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Athanassiou, A. . . . . . . . . . . . . . . . . . . . . . . . . .194Attar, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226Atzmon, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26August, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Auliff, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Auriane, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Averback, R.S. . . . . . . . . . . . . . . . . . . . . . .115, 267Avila Paredes, H.J.* . . . . . . . . . . . . . . . . . . . . . . .72Avila-Davila, E.O. . . . . . . . . . . . . . . . . . . . . . . . .75Avila-Paredes, H. . . . . . . . . . . . . . . . . . . . . . . . . .72Aviles, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Avishai, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Awaji, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Awano, M. . . . . . . . . . . . . . . . . . . . . . . . . .102, 171Awano, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Ayayee, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .215Ayers, J.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Aytug, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Azari, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Azizi-Alizamini, H.* . . . . . . . . . . . . . . . . . . . . .120Azurdia, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .129

B

Babaghorbani, P. . . . . . . . . . . . . . . . . . . . . . . . .229Babu, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125Babu, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Babu, S.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216* Indicates Presenting Author

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 272

www.matscitech.org 273

Author Index

Baca, F.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Baca, J.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Bache, M.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .260Bacon, D.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Baddorf, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Badillo, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .267Badrina, K.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Bae, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193, 194Bae, C.* . . . . . . . . . . . . . . . . . . . . . . . . .85, 193, 194Bae, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130Baek, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Baek, S.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Baeslack, W.A.* . . . . . . . . . . . . . . . . . . . . . . . . . .92Baeumer, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Bagot, P.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Baharvandi, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .30Bahmanpour, H.* . . . . . . . . . . . . . . . . .21, 31, 134Bahr, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Bahr, D.F. . . . . . . . . . . . . . . . . . . . . . . . . . . .65, 101Bahr, D.F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Bahr, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Bai, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Bai, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Bai, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Baily, S.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Bain, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167Bain, J.A. . . . . . . . . . . . . . . . . . . . . . . . . . . .167, 205Baker, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22, 269Baker, I.* . . . . . . . . . . . . . . . . . . . . . . .186, 225, 254Bakhshi, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Bakshi, S.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Bal, S.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23, 82Balachandran, U. . . . . . . . . . . . . . . . . . . . . . . . .100Balani, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Balasubramaniam, K. . . . . . . . . . . . . . . . . . . . . .62Balasubramaniam, K.R. . . . . . . . . . . . . . . . . . . .72Baldo, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Baldo, P.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Balikci, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Balint, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Balla, V.K.* . . . . . . . . . . . . . . . . .122, 251, 271, 272Ballato, J.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Ballinger, R.G.* . . . . . . . . . . . . . . . . . . . . . . . . .144Balogun, S.A. . . . . . . . . . . . . . . . . . . . . . . . . . . .136Balzarotti, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Ban, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Banaag, M.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Bandyopadhyay, A. . . .28, 122, 129, 190, 210, 251,

270, 271, 272Banerjee, R. . . . . .19, 117, 130, 247, 248, 249, 271Banerjee, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .122Banker, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Bansiddhi, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .154Baram, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Barber, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Barbero, J.I.* . . . . . . . . . . . . . . . . . . . . . . . . . . .120Barbieri, L. . . . . . . . . . . . . . . . . . . . . . . . . . . .9, 143Bardez, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Barmak, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Barnes, A.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Barnes, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Barnes, P.N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Barnett, S.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Barney, I.T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .196Baroghel-Bouny, V.* . . . . . . . . . . . . . . . . . . . . . .50Bar-On, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232Barseghyan, S.* . . . . . . . . . . . . . . . . . . . . . . . . . .26Barsoum, M.* . . . . . . . . . . . . . . . . . . . . . .173, 181Barsoum, M.W. . . . . . . . . . .73, 112, 163, 173, 181Barsoum, M.W.* . . . . . . . . . . . . . . . . . . . . . . . .173Bartolo, L.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Bartwal, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Basavaraj, D.H. . . . . . . . . . . . . . . . . . . . . . . . . .229Bassim, N.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95Basu, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52Basu, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Basu, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .112, 181Bataille, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .106Bathias, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .108Bauer, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Baumann, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . .270Bayles, B.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Beach, E. . . . . . . . . . . . . . . . . . . . . . . . . . . .139, 261Beach, E.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Beaudoin, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Beaudoin, J.J. . . . . . . . . . . . . . . . . . . . . . . . . . . .155Beavers, J.A. . . . . . . . . . . . . . . . . . . . . . . . . .42, 147Becher, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Becher, P.F. . . . . . . . . . . . . . . . . . . . . . . . . . .69, 176Beck, D.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Beck, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Becker, C.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .42Becker, K.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . .213Becker, M.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .232Béclin, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Bedi, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Bedzyk, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Beers, S.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Behera, S.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .267Beitelman, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Bejan, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Bejan, S.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Beladi, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Bell, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Bellhouse, E.M.* . . . . . . . . . . . . . . . . . . . . . .22, 47Bellon, P.M.* . . . . . . . . . . . . . . . . . . . . . . .115, 267Bellou, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65Belokon, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Belova, I.V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Bender, B.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Beniash, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49Benicewicz, B.C. . . . . . . . . . . . . . . . . . . . . . . . . .86Benitez, C.F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Benmore, C.J. . . . . . . . . . . . . . . . . . . . . . . . . . . .198Bennet, K.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Benoit, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Bentley, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Benz, J.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Beratan, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Bercia, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Bergendahl, J.A. . . . . . . . . . . . . . . . . . . . . . . . . .236Berger, J.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Berghmans, A. . . . . . . . . . . . . . . . . . .128, 182, 268Berhan, M.N.* . . . . . . . . . . . . . . . . . . . . . . . . . . .21Bermúdez-Reyes, B. . . . . . . . . . . . . . . . . . .222, 272Bernier, J.V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Bernthaler, T.* . . . . . . . . . . . . . . . . . . . . . . . . . .178Berry, D.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Bertrand, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Besser, M.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226Bestor, M.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .246Bhadeshia, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .81Bhaduri, S.B.* . . . . . . . . . . . . . . . . . . . . . . . . . .222Bhalla, A. . . . . . . . . . . . . . . . . .7, 36, 166, 202, 263Bhalla, A.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .6, 96Bharadwaja, S.* . . . . . . . . . . . . . . . . . . . . . . . . .204Bhattacharjee, A. . . . . . . . . . . . . . . . . . . . . . . . .177Bhujang Mutt, G. . . . . . . . . . . . . . . . . . . . . . . . .263Bhujang Mutt, S.* . . . . . . . . . . . . . . . . . . . . . . .263Bi, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Bian, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Bibler, N.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99

Biegalski, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95Biegalski, M.D. . . . . . . . . . . . . . . . . . . . . . . . . . . .63Bieler, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Bieler, T.R.* . . . . . . . . . . . . . . . . . . . . . . . . .99, 151Biener, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Biener, M.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Biering, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Biernacki, J.J.* . . . . . . . . . . . . . . . . . . . . . . . . . .123Biglari, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Bilitz, E.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Billings, K.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . .39Bingham, P.A. . . . . . . . . . . . . . . . . . . . . . . . . . .170Birnie, D.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Birnie,III, D.P. . . . . . . . . . . . . . . . . . . . . . . . . . .195Biser, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106Bitschi, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Blamire, M.G. . . . . . . . . . . . . . . . . . . . . . . . . . .168Blendell, J.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Blohowiak, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .212Blue, C.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113Blunk, R.H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Bobnar, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Boccacccini, D.N. . . . . . . . . . . . . . . . . . . . . . . . . . .9Bocher, L. . . . . . . . . . . . . . . . . . . . . . . . . . .145, 146Boddapati, S.* . . . . . . . . . . . . . . . . . . . . . . . . . .199Bodhak, S.* . . . . . . . . . . . . . . . . . . . . . .28, 190, 210Bodnar, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Boehlert, C.J.* . . . . . . . . . . . . . . . . . . . . . .179, 248Boettinger, W. . . . . . . . . . . . . . . . . . . . . . . . . . .240Boettinger, W.J. . . . . . . . . . . . . . . . . . . . . . . . . .114Bohsmann, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .58Bolander, M.E. . . . . . . . . . . . . . . . . . . . . . . . . . . .82Bolton, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42Bonakdar, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Bond, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Bonneville, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .137Bontha, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .32, 54Booth, J.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Booth-Morrison, C. . . . . . . . . . . . . . . . . . . . . . .45Booty, M.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Borchardt, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Borges, M.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Borgesen, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Borisevich, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Bose, S. .28, 122, 129, 190, 210, 251, 270, 271, 272Bosse, J. . . . . . . . . . . . . . . . . . . . . . . . .165, 186, 230Botero, E.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Böttger, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247Böttner, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Bouler, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .270Bourell, D.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Bouza, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Bovtun, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Bowan, B.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Bowan, B.W.* . . . . . . . . . . . . . . . . . . . . . . . . . . .143Bowman, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Bowman, K.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .37Boyce, B.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .181Boykin, T.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .176Boyne, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Brack, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Brada, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Bradshaw, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .125Brahmandam, S. . . . . . . . . . . . . . . . . . . . . . . . .199Brahme, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74Branagan, D.J.* . . . . . . . . . . . . . . . . . . . . .135, 271Brandes, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Brantley, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . .122Braun, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Brazier, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .159Breeze, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 273

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania274

Author Index

Brennecka, G.L. . . . . . . . . . . . . . . . . . . . . . . . . .248Brennecka, G.L.* . . . . . . . . . . . . . . . . . . . . . . . .257Brenneman, R.G.* . . . . . . . . . . . . . . . . . . . . . . .189Brewer, L.N. . . . . . . . . . . . . . . . . . . . . . . . . .64, 248Brewster, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Brian, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Brinker, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93Brinson, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Brinson, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Briselden, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .235Brochu, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Brockenbrough, J. . . . . . . . . . . . . . . . . . . . . . . .148Brommer, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Bronk, J.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Brooks, C.M. . . . . . . . . . . . . . . . . . . . . . . . . . . .117Brosius, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Brow, R.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19Brown, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .252Brown, H.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Brown, L.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Brown, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Brown, R.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .54Brown, R.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Browne, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106Browning, N.D. . . . . . . . . . . . . . . . . . . . . . . . . .217Brown-Shaklee, H.J.* . . . . . . . . . . . . . . . . . . . .132Bruce, R.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Bruncko, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Brundidge, C.L.* . . . . . . . . . . . . . . . . . . . . . . . .178Brus, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Bryant, S.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Bubeck, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Buchanan, D. . . . . . . . . . . . . . . . . . . . . . . . . . . .245Buchanan, D.* . . . . . . . . . . . . . . . . . . . . . . . . . .245Buchanan, D.J. . . . . . . . . . . . . . . . . . . . . . . . . . . .71Buchanan, R.C. . . . . . . . . . . . . . . . . . . . . . . . . .203Buchholz, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Büchler, P.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Buchmann, M.E. . . . . . . . . . . . . . . . . . . . . . . . . .57Budai, J.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Bueno, P.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Buhr, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Bui, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Buie, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Buldakov, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Bullard, J.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Bullard, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Bulmer, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Bumrongjaroen, W.* . . . . . . . . . . . . . . . . . . . . . .50Burbure, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .167Buresch, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Burgess, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Burghardt, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Burka, L.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Burke, P.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95Burkes, D.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Burket, P.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265Burkett, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Burns, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Burns, M.G.* . . . . . . . . . . . . . . . . . . . . . . . . . . .148Burrell, A.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Buta, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Butt, D.P. . . . . . . . . . . . . . . . . . . . . . . . . . .158, 206Buttlar, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Buttrill, W.H. . . . . . . . . . . . . . . . . . . . . . . . . . . .179Buyukhatipoglu, K.* . . . . . . . . . . . . . . . . . . . . .155Buzaianu, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Bykowski, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .79Byrne, K.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .271Byun, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

C

Cabioc’h, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85Cadney, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Cahn, J.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238Cai, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Caillat, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Caillat, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Calamino, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Calcagnotto, M. . . . . . . . . . . . . . . . . . . . . . . . . . .80Calderón, H.E.* . . . . . . . . . . . . . . . . . . . . . . . . . .21Callejo, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Callender, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Calvert-Doyle, K.* . . . . . . . . . . . . . . . . . . . . . . .254Calvo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .119, 120Campbell, C.* . . . . . . . . . . . . . . . . . . . . . .151, 176Campbell, G.H.* . . . . . . . . . . . . . . . . . . . . . . . .217Campbell, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .177Cann, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Cann, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Canon, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Cantournet, S. . . . . . . . . . . . . . . . . . . . . . . . . . .214Cantres, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Cao, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259Cao, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Cao, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Cao, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Cao, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4, 230Cao, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Capocchi, J.T. . . . . . . . . . . . . . . . . . . . . . . . .31, 229Caputo, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .194Caram, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Caram, H.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Caram, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Cardello, J.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23Cardona, Y.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Cardona, Y.P.* . . . . . . . . . . . . . . . . . . . . . . .17, 263Cardoso, F.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Caris, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .36, 156Carlson, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211Carmel, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141Caro, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115Carrasquillo, R.* . . . . . . . . . . . . . . . . . . . . . . . .136Carrillo, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Carter, E.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Carter, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227Carter, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232Carter, W.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .176Carty, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Case, E.D. . . . . . . . . . . . . . . . . . . . . . .175, 209, 270Case, E.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Casey, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Cashman, G.T. . . . . . . . . . . . . . . . . . . . . . . . . . .178Cashman, G.T.* . . . . . . . . . . . . . . . . . . . . . . . . .178Cass, R.B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101Castellano, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Catalina, A.V.* . . . . . . . . . . . . . . . . . . . . . . . . . . .74Caton, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242Caton, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Caurant, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Cavicchi, R.E. . . . . . . . . . . . . . . . . . . . . . . . . . . .203Cebon, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .237Cen, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Cerezo, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Cerreta, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Cerreta, E.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Cerully, L.B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Cervera, R.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Cha, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Cha, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Chakraborty, T.* . . . . . . . . . . . . . . . . . . . . . . . .263

Chamat, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Chan, H.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Chan, H.M.* . . . . . . . . . . . . . . . . . . . . . . . .14, 106Chan, K.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Chan, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Chan, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Chancey, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Chandramouli, K. . . . . . . . . . . . . . . . . . . . . . . .231Chandran, K. . . . . . . . . . . . . . . . . . . . . . . . .71, 184Chandran, K.* . . . . . . . . . . . . . . . . . . . . . . .71, 158Chandran, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . .129Chandran, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .178Chandrasekar, S. . . . . . . . . . . . . . . . . . . . . . . . .254Chang, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8, 13Chang, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3, 6Chang, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Chang, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Chang, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Chang, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Chang, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .178Chang, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Chang, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Chao, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10, 100Chao, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9, 141Charit, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88Charit, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Chartier, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Chaswal, V.* . . . . . . . . . . . . . . . . . . . .203, 245, 247Chatain, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Chatterjee, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .273Chatterjee, M. . . . . . . . . . . . . . . . . . . . . . . . . . .121Chatterjee, M.* . . . . . . . . . . . . . . . . . . . . . . . . .121Chaudhuri, S.K. . . . . . . . . . . . . . . . . . . . . . . . . .153Chaudhury, R.P. . . . . . . . . . . . . . . . . . . . . . . . . .202Chaves, M.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Chavez, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .59, 60Chavez, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Chawla, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90Chawla, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Chawla, N.* . . . . . . . . . . . . . . . . . . . . .55, 194, 211Chen, B. . . . . . . . . . . . . . . . . . . . . . . . . . . .259, 260Chen, C. . . . . . . . . . . . .36, 166, 202, 215, 229, 263Chen, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39Chen, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Chen, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .180, 258Chen, H.* . . . . . . . . . . . . . . . . . . . . . . . . . .102, 230Chen, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Chen, I.* . . . . . . . . . . . . . . . . . . . . . . . .52, 165, 167Chen, I.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125Chen, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Chen, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Chen, L. .16, 19, 59, 75, 95, 96, 150, 151, 174, 185,

217Chen, L.* . . . . . . . .36, 91, 165, 166, 168, 262, 267Chen, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Chen, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Chen, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Chen, S. . . . . . . . . . . . . . . . . . . . . . . .107, 120, 186Chen, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Chen, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Chen, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130Chen, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Chen, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Chen, Y. . . . . . .9, 25, 40, 61, 96, 238, 253, 262, 264Chen, Y.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70Chen, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Chen, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .155Cheng, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Cheng, H. . . . . . . . . . . . . . . . . . . . . . . .89, 250, 257Cheng, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Cheng, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 274

www.matscitech.org 275

Author Index

Cheng, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .30, 38Cheng, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Cheng, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Cheng, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Cheon, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Cherry, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Chevalier, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Chi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Chiang, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Chiaramonti, A. . . . . . . . . . . . . . . . . . . . . . . . . .185Chichkov, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Chien, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Chin, E.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85Chin, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81Ching, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Ching, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265Chintaiah, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Chiofalo, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . .221Chiou, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212Chisholm, B. . . . . . . . . . . . . . . . . . . . . . . . . . . .190Chisholm, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . .190Chisholm, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .229Cho, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Cho, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28Cho, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Cho, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Cho, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22Cho, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80, 253Chockalingam, R.* . . . . . . . . . . . . . . . . . . . . . .110Chockalingam, S. . . . . . . . . . . . . . . . . . . . . . . . .110Choi, A.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Choi, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226Choi, E. . . . . . . . . . . . . . . . . . . . . . . . . . . .18, 27, 29Choi, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22Choi, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130Choi, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34, 171Choi, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .172, 206Choi, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6, 36Choi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Choi, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167Choi, S.R. . . . . . . . . . . . . . . . . . . . . . . . . . . .25, 198Choi, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Chokshi, A.H. . . . . . . . . . . . . . . . . . . . . . . . . . .187Chou, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . .145, 171Choudhary, P.* . . . . . . . . . . . . . . . . . . . . . . . . . .121Choudhuri, D.* . . . . . . . . . . . . . . . . . . . . . . . . . .38Choudhury, S. . . . . . . . . . . . . . . . .95, 96, 185, 262Choudki, B.L.* . . . . . . . . . . . . . . . . . . . . . . . . . .153Chowdhury, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Christen, H.M.* . . . . . . . . . . . . . . . . . . . . . . . . . .63Christianson, D. . . . . . . . . . . . . . . . . . . . . . . . . .190Christien, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .238Christodoulou, L.* . . . . . . . . . . . . . . . . . . . . . . .55Chu, B.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Chu, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202Chu, J.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Chu, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Chueh, W.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .110Chumbley, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Chung, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22Chung, C.* . . . . . . . . . . . . . . . . . . . . . . . . .123, 124Ciecinska, M. . . . . . . . . . . . . . . . . . . . . . . . . . .8, 26Cieslinski, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .160Cincotto, M.A. . . . . . . . . . . . . . . . . . . . . . . . . . . .83Cingolani, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .194Cintho, O.M. . . . . . . . . . . . . . . . . . . . . . . . .31, 229Cintron-Aponte, A.* . . . . . . . . . . . . . . . . . . . . . .18Ciski, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .152Civale, L. . . . . . . . . . . . . . . . . . . . . . . . .93, 231, 264Clark, C.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Clark, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122

Clarke, D.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Clarke, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Clasen, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249Cochran, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250Cochran, J.K. . . . . . . . . . . . . . . . . . . . . . . . . . . .119Colanto, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Cole, J.I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Cole, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Cole, M.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164Cole, M.W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Collazo, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Collins, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Collins, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Collins, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Collins, J.G.* . . . . . . . . . . . . . . . . . . . . . . . .74, 179Collins, P. . . . . . . . . . . . . . . . . . . . . . . . . . .186, 243Colpetzer, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Compson, C.* . . . . . . . . . . . . . . . . . . . . . . . . . .256Comyn, T.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Conrad, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .186Conrad, T.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Constantinescu, S. . . . . . . . . . . . . . . . . . . . . . . . .75Contreras-García, M. . . . . . . . . . . . . . . . . . . . . .25Contreras-García, M.* . . . . . . . . . . .159, 222, 272Converse, G.L. . . . . . . . . . . . . . . . . . . . . . . . . . .221Cook, L.P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203Cooke, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Cooper, K.P.* . . . . . . . . . . . . . . . . . . . . . . . . . . .160Coors, G.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .172Copley, S.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .255Cora, O.N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .188Cormack, A.N.* . . . . . . . . . . . . . . . . . . . . . . . . .149Cormode, T.A. . . . . . . . . . . . . . . . . . . . . . . . . . . .78Corral, E.L.* . . . . . . . . . . . . . . . . . . . . . . . . .88, 225Correa, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Cortese, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194Cosandey, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . .140Cottrell, M.A.* . . . . . . . . . . . . . . . . . . . . . . . . . .231Cotts, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Cotts, E.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Coughlin, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Coulon, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214Coulter, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .237Counts, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .147Cozzi, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Cozzoli, D.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .194Craft, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Craiu, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Crampon, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .106Crawford, C.L. . . . . . . . . . . . . . . . . . . . . . . . . . .265Crawford, G. . . . . . . . . . . . . . . . . . . . . . . . . . . .194Cremasco, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .123Crimp, M.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Cristea, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Cross, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94Crowell, M.W.* . . . . . . . . . . . . . . . . . . . . . . . . .126Crum, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .169, 234Crum, J.V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .234Cruz, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Cruz, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Cruz, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Cui, X.T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Cunningham, D.J.* . . . . . . . . . . . . . . . . . . . . . .160Curiotto, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Curtarolo, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .42Curtin, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Cuvanova, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

D

Daemen, L.L. . . . . . . . . . . . . . . . . . . . . . . . . . . .173

Dahlben, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236Dahotre, N.B. . . . . . . . . . . . . . .26, 86, 90, 113, 255Daigle, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Dair, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254Dandeneau, C. . . . . . . . . . . . . . . . . . . . . . . . . . .213Dang, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Dangla, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Daniels, J. . . . . . . . . . . . . . . . . . . . . . . . . . .190, 231Daniels, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Daniels, J.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94Danilov, V.I. . . . . . . . . . . . . . . . . . . . . . . . . . . . .156Dantal, B.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .142Darling, K.A. . . . . . . . . . . . . . . . . . . . . . . . . . . .152Darsell, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .198Das, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31Das, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Das, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Das, R.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Das, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193Das, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Dastane, R.R. . . . . . . . . . . . . . . . . . . . . . . . . . . .235Dauskardt, R.* . . . . . . . . . . . . . . . . . . . . . . . . . .212Dávalos-de la Cruz, K.V. . . . . . . . . . . . . . . . . . . .23Davenport, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .23David, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Day, J.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Dayananda, M.A.* . . . . . . . . . . . . . . . . . . . . . . .183De Cooman, B.C.* . . . . . . . . . . . . . . . . . . . . . . . .48De Graef, M. . . . . . . . . . . . . . . . . . . . . . . . .62, 166De Graef, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .218De Guire, M.R. . . . . . . . . . . . . . . . . . . . . . . . .65, 66De Souza, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .213De Yoreo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Dea Hwan, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Deacon, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .192DeArdo, A.J. . . . . . . . . . . . . . . . . . . . . . . . .118, 188DeBastiani, D.L. . . . . . . . . . . . . . . . . . . . . . . . . .189DeCarlo, K.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .14Deceuster, A. . . . . . . . . . . . . . . . . . . . . . . .134, 260DeFrain, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .35, 57Deibler, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126dela Cruz, C.R. . . . . . . . . . . . . . . . . . . . . . . . . . .202DelRegno, G.E. . . . . . . . . . . . . . . . . . . . . . . . . .102Delvasto, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .155Demaree, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Deneele, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Dennies, D.P.* . . . . . . . . . . . . . . . . . . . . . . . . . .108Desai, P.G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Desai, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Deshpande, A.S. . . . . . . . . . . . . . . . . . . . . . . . . . .49Detrez, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214Deutsch, T. . . . . . . . . . . . . . . . . . . . . . . . . .215, 246Deva, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Devanathan, R.* . . . . . . . . . . . . . . . . . . . . . . . . .67Devaraj, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .271DeVasConCellos, P. . . . . . . . . . . . . . . . . . . . . . .272Devine, B.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Devrani, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Devrani, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .182DeVries, P.H.* . . . . . . . . . . . . . . . . . . . . . . . . . . .42Dexheimer, S.L.* . . . . . . . . . . . . . . . . . . . . . . . .117Dey, S.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50DiAntonio, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6DiAntonio, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .59DiAntonio, C.B. . . . . . . . . . . . . . . . . . . . . . . . . . .60Dias, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Diatlova, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Diaz, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Dickey, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Dickinson, M.E.* . . . . . . . . . . . . . . . . . . . . . . . .254Dieckmann, R. . . . . . . . . . . . . . . . . . . . . . . . .17, 26

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 275

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania276

Author Index

Dillon, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Dillon, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .105, 238Dillon, S.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Dimitrov, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Dinan, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Diomampo, M.H. . . . . . . . . . . . . . . . . . . . . . . . .34DiPietro, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Dispensa, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79Dixit, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .186Dkhil, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Do, T.B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141Dockal, E.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Doering, K.T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .42Dogan, F. . . . . . . . . . . . . . . . . . . . . .9, 23, 141, 165Dogan, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Dogan, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Doherty, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .250Doll, G.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249Dombrowski, D.E. . . . . . . . . . . . . . . . . . . . . . . .227Dominguez, O.* . . . . . . . . . . . . . . . . . . . . . . .11, 29Dong, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Dong, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Dong, Q.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70Dong, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138Dong, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Donnelly, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Donnelly, N.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .17Doraiswamy, A. . . . . . . . . . . . . . . . . . . . . . . . . . .82Dorantes-Rosales, H.J. . . . . . . . . . . . . . . . . . . . .75Doreen, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110Dorr, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137Dorsey, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Dorsey, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125dos Santos, J.F. . . . . . . . . . . . . . . . . . . . . . . . . . .134Dougherty, L.M.* . . . . . . . . . . . . . . . . . . . . . . .220Doumanidis, H. . . . . . . . . . . . . . . . . . . . . . . . . .136Doyon, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .252Dragan, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .3, 138Dragomir-Daescu, D.* . . . . . . . . . . . . . . . . . . . .82Drake, T.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Dravid, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91Dravid, V.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Dregia, S.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Drew, R.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249Drew, R.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250Droopad, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .167Drye, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Drymiotis, F.* . . . . . . . . . . . . . . . . . . . . . . . . . .174DSouza, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259Du, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90Du, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Du, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Duarte, L.I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Dubey, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Dubois, S.* . . . . . . . . . . . . . . . . . . . . . .85, 137, 181Dudina, D.V. . . . . . . . . . . . . . . . . . . . . . . . . . . .219Dudu, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Dukes, D.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Duman, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224Dunand, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .183Dunand, D.* . . . . . . . . . . . . . . . . . . . .122, 154, 247Duong, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66DuPont, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Durnford, A.T. . . . . . . . . . . . . . . . . . . . . . . . . . .239Dutta, A.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Dutta, A.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31Dutta, B. . . . . . . . . . . . . . . . . . . . . . . . . . . .226, 259Dutta, B.* . . . . . . . . . . . . . . . . . . . . . . . . . .255, 259Dutta, P.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Dutta, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .14, 106Duty, C.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114

Duval, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Duxson, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125Dybkov, V.I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Dyess, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261Dynys, F. . . . . . . . . . . . . . . . . . . . . . . . . . . .171, 231Dynys, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .171

E

Eakins, D.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Earthman, J.C.* . . . . . . . . . . . . . . . . . . . . . . . . .212Eastman, J.A. . . . . . . . . . . . . . . . . . . . . . . . . . . .116Eastmann, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Ebert, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Ebrahimi, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .252Ebrahimi, M.E.* . . . . . . . . . . . . . . . . . . . . . .97, 103Eckerlebe, H. . . . . . . . . . . . . . . . . . . . . . . . . .27, 30Eckert, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Economy, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Edacherian, A. . . . . . . . . . . . . . . . . . . . . . . . . . .136Eden, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Edwards, D.D. . . . . . . . . . . . . . . . . . . .10, 149, 180Edwards, T.B. . . . . . . . . . . . . . . . . . . . . . . .169, 170Egelhoff, W.F. . . . . . . . . . . . . . . . . . . . . . . . . . . .203Eggeler, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248Ehsani, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Eichel, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Eiken, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247Eilaghi, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Einarsrud, M. . . . . . . . . . . . . . . . . . . . . . . . .66, 166Eiras, J.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Eisenlohr, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Ekerdt, J.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257Elblbesy, M.A.* . . . . . . . . . . . . . . . . . . . . . . . . . .49Elder, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112El-Eswed, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .208Eliezer, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Eliezer, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Eliseev, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .27, 225Eliseev, A.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Eliseev, E.A. . . . . . . . . . . . . . . . . . . . . . . . . .59, 185El-Kabir, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137El-Mahallawy, N.A. . . . . . . . . . . . . . . . . . . . . . .273Elmaryami, A.* . . . . . . . . . . . . . . . . . . . . . . . . . .48El-Raghy, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .101Elsaesser, C. . . . . . . . . . . . . . . . . . . . . . . . . .12, 106El-Shabasy, A.B. . . . . . . . . . . . . . . . . . . . . . . .24, 28Elwazri, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Elwazri, A.* . . . . . . . . . . . . . . . . . . . . . . . . .80, 119Endo, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Endo, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Engström, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .114Enright, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242Eom, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96, 262Eom, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .39, 262Eom, C.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233Epicier, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Erb, U. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Erdeniz, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Erdeniz, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Erdman, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Erdogan, S.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Erdrin, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Ericksen, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Ernst, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47, 247Ernst, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Esezobor, D.E. . . . . . . . . . . . . . . . . . . . . . . . . . .136Esfehanian, M.* . . . . . . . . . . . . . . . . . . . . . . . . .224Esparza, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Espinoza-Beltrán, F. . . . . . . . . . . . . . . . . . . . . .222Espinoza-Medina, M. . . . . . . . . . . . . . . . . . . . . .25

Espitia, M.I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Espitia-Cabrera, I. . . . . . . . . . . . . . . . . . . .222, 272Esposito, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .129Es-Souni, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .250Estevane, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Estremera, E.G. . . . . . . . . . . . . . . . . . . . . . . . . . .32Eswaramoorthy, S.K. . . . . . . . . . . . . . . . . . . . . .266Evans, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55Evans, A.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Evans, N.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .217Evans, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Evans, R.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249Evteev, A.V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Ewh, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Ewing, R.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Ewsuk, K.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .130

F

Fabbreschi, M. . . . . . . . . . . . . . . . . . . . . . . . . . .221Faber, K.T. . . . . . . . . . . . . . . . . . . . .34, 58, 88, 155Faber, K.T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Fabian, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Faeghi-Nia, A.* . . . . . . . . . . . . . . . . . . . . . . . . . .88Fahrenholtz, B. . . . . . . . . . . . . . . . . . . .30, 131, 132Fahrenholtz, W. . . . . . . . . . .30, 132, 192, 249, 256Fahrenholtz, W.G. . . . . . . . . .31, 44, 132, 161, 192Faierson, E.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .158Falk, M.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115Fall, M.L. . . . . . . . . . . . . . . . . . . . . . . . . . .128, 194Fall, M.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Fallahi, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Fan, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Fan, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Fan, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25, 238Fan, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Fan, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235Fang, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214Fang, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Fantozzi, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Farag, M.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Farahany, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Farahmand, B. . . . . . . . . . . . . . . . . . . . . . . . . . .242Farias, F.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31Farooqi, J.K.* . . . . . . . . . . . . . . . . . . . . . . . .16, 211Farooque, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .145Fashanu, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Fatehi, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Fekete, J.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188Feldmann, D.M. . . . . . . . . . . . . . . . . . . . . . . . . . .93Feller, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Feng, C.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Feng, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Feng, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Feng, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .271Fenoglio, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211Ferarrelli, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Fergus, J.W. . . . . . . . . . . . . . . . . . . . . . . . . . . .35, 57Ferguson, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Ferrand, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Ferreira de Souza, D.P. . . . . . . . . . . . . . . . . . . . .11Ferreira, P.D. . . . . . . . . . . . . . . . . . . . . . . . . . . .232Feteira, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .37, 61Fett, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224Fields, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Fife, J.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247Fikru, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .272Filip, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Finkel, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Finkel, M.* . . . . . . . . . . . . . . . . . . . . . . . . .156, 175Fiore, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 276

www.matscitech.org 277

Author Index

Fiory, A.T. . . . . . . . . . . . . . . . . . . . . . . . . . .182, 268Firdosy, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Firrao, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Fischman, G.* . . . . . . . . . . . . . . . . . . . . . . . . . .163Fisher, C.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Fisher, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Fister, T.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Fitelson, M. . . . . . . . . . . . . . . . . . . . . . . . .182, 268Flage-Larsen, E.* . . . . . . . . . . . . . . . . . . . . . . . .174Flatt, R.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Fleig, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .17, 179Fleig, P.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101Fleurial, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .67, 208Fliflet, A.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Floquet, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Flores, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Flores-García, J.C. . . . . . . . . . . . . . . . . . . . . . . . .30Flower, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Folkman, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Foltyn, S.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Foltz, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Fonda, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249Fong, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72, 95Fong, D.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Foreman, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .137Foroozmehr, E.* . . . . . . . . . . . . . . . . . . . . . . . . .260Forsdike, J.P.* . . . . . . . . . . . . . . . . . . . . . . . . . . .260Forsman, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .235Forster, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Fouchet, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Fourment, L. . . . . . . . . . . . . . . . . . . . . . . . . . . .133Fournier Dit Chabert, F. . . . . . . . . . . . . . . . . . .238Fowler, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Fox, K.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Fox, K.M.* . . . . . . . . . . . . . . . . . . . . . . . . .143, 169Frafjord, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Franck, B.* . . . . . . . . . . . . . . . . . . . . . . . . .187, 243Franco, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .222Franetovic, V. . . . . . . . . . . . . . . . . . . . . . . . . . . .223Fraser, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248Fraser, H.L. . . . . . .19, 117, 122, 186, 243, 247, 248Fredenburg, D.A.* . . . . . . . . . . . . . . . . . . . . . . .250Freels, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212Freeman, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Freeman, A.J. . . . . . . . . . . . . . . . . . . . . . . . . .14, 15Freitag, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . .41, 64Frenkel, A.I. . . . . . . . . . . . . . . . . . . . . . . . .183, 218Friák, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .147Friak, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Friddle, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Fridy, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .148Friedman, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Fu, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Fu, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23, 82Fu, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Fujii, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .183Fujimoto, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Fujishiro, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Fujishiro, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .171Fujita, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202Fujiwara, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Fukamachi, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .36Fukase, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .271Fukuda, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Fukuhara, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Fukui, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Fukui, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Fukushima, M.* . . . . . . . . . . . . . . . . . . . . . . . . .208Fukushima, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . .220Fullen, W.J.* . . . . . . . . . . . . . . . . . . . . . . . .237, 265Fuller, E.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .239

Funahashi, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .68Funakubo, H.* . . . . . . . . . . . . . . . . . . . . . . . .61, 91Fuoss, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Fuoss, P.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Furukawa, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Furuya, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Fusco, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Fuse, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126

G

Gaikwad, V.B.* . . . . . . . . . . . . . . . . . . . . . . . . . .205Gairola, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .129Galgali, B.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Galloway, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Gammill, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . .256Gan, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Gan, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40, 104Ganeff, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79Ganeshan, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .247Gangireddy, S. . . . . . . . . . . . . . . . . . . . . . . . . . .133Gangireddy, S.* . . . . . . . . . . . . . . . . . . . . . . . . .132Ganguly, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Ganzarain, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Gao, H.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70Gao, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .98, 177Gao, M.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Gao, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Garai, S.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Garas, V.Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Garay, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Garay, J.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Garboczi, E.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .83Garcia, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259Garcia, C. . . . . . . . . . . . . . . . . . . . . . . . . . .118, 188Garcia, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Garcia, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Garcia, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .61, 66García-Benjume, M. . . . . . . . . . . . . . . . . . . . . .159García-Gonzáles, L. . . . . . . . . . . . . . . . . . . . . . . .26Garg, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Garmestani, H. . . . . . . . . . . . . . . . . . . . . . . . . . .78Garofalini, S.* . . . . . . . . . . . . . . . . . . . . . . . . . .210Garofalini, S.H. . . . . . . . . . . . . . . . . . . . . . . . . . .10Garofano, J.K.* . . . . . . . . . . . . . . . . . . . . . . . . . .249Garrabou, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Garrison, W. . . . . . . . . . . . . . . . . . . . . . . . .121, 153Gasch, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .27, 131Gauthier, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Gauthier, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . .181Gauthier-Brunet, V. . . . . . . . . . . . . . . . . . . .85, 137Gawalt, E.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .270Gaytan, S.M. . . . . . . . . . . . . . . . . . . . . . . . . . . .122Gazzotti, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Gearing, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .137Geiger, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Geiger, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Gell, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Geltmacher, A.B.* . . . . . . . . . . . . . . . . . . . . . . .210Gemeiner, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Gemmen, R. . . . . . . . . . . . . . . . . . . . .207, 234, 238Gemmen, R.S. . . . . . . . . . . . . . . . . . . . . . . . . . .235Gendre, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Genelin, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Gentile, P.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .102George, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Gerdes, K. . . . . . . . . . . . . . . . . . . . . . . . . . .143, 238Gerdes, K.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Gerfen, J.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Gerogiorgis, D.I.* . . . . . . . . . . . . . . . . . . . . . . . .74Gerosa, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221

Gerstl, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Ghasemiarmaki, H. . . . . . . . . . . . . . . . . . . . . . . .21Ghedini, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Ghonem, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .188Ghosal, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Ghosh, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Ghosh, N.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Ghosh, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Ghosn, L.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Gibbons, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Gibbons, B.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Gierisch, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Giles, M.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Gilgert, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Gill, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .244Gill, P.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Gill, P.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Gillaspie, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Gilles, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Gin, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257Gin, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Gin, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Ginley, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Giri, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Gitis, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214Giulian, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Giurgiutiu, V. . . . . . . . . . . . . . . . . . . . . . . . .36, 202Glaeser, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Glam, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Glans, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Glass, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Gleeson, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Gleeson, B.M. . . . . . . . . . . . . . . . . . . . . . . . . . . .157Glicksman, M. . . . . . . . . . . . . . . . . . . . . . . . . . .112Gnade, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Godoi, G.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Goerke, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Goettert, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Goh, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130Goian, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Goin, R.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135Gokhale, A.M.* . . . . . . . . . . . . . . . . . . . . .148, 210Gold, S.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Goldschmidt, M. . . . . . . . . . . . . . . . . . . . . . . . .220Goldstein, P.R. . . . . . . . . . . . . . . . . . . . . . . . . . . .91Golestani-Fard, F. . . . . . . . . . . . . . . . . . . . . . . .189Gomez, G.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Gomez, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Gómez-Zamorano, L.Y. . . . . . . . . . . . . . . . . . . . .83Gong, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .234González Hernández, I. . . . . . . . . . . . . . . . . . . . .23Gonzalez, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Gonzalez, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Gonzalez-Velazquez, J.L. . . . . . . . . . . . . . . . . . . .75Goodall, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Goodarzi, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .31Goods, S.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Gopalan, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Goran, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250Gorbunov, V. . . . . . . . . . . . . . . . . . . . . . . . . . . .142Gordon, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Gorman, B.P.* . . . . . . . . . . . . . . . . . . . . . .232, 249Gorzkowski, E.P. . . . . . . . . . . . . . . . . . . . . .37, 202Gorzkowski, E.P.* . . . . . . . . . . . . . . . . . . . . . . .141Goswami, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .101Gothard, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . .104Goto, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Gottlieb, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Goudy, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164Gould, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Gout, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 277

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania278

Author Index

Gower, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .159Goyal, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Goyal, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .273Goyal, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Goyal, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193Grabowski, B. . . . . . . . . . . . . . . . . . . . . . . . . . . .216Grabulov, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .109Graeve, O.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .257Graeve, O.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .226Graham, G.W. . . . . . . . . . . . . . . . . . . . . . . . . . .106Grambow, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Granasy, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Grande, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .51, 66Grande, T.* . . . . . . . . . . . . . . . . . . . . . . . . .109, 166Grant, G.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133Granzow, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .231Grasley, Z.C.* . . . . . . . . . . . . . . . . . . . . . . . . .50, 63Graule, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Gray III, G.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Gray, G.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Gray, G.T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107Green, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Green, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Green, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203Green, M.L. . . . . . . . . . . . . . . . . . . . . . . . . . .53, 95Gregory, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188Gremillard, L.* . . . . . . . . . . . . . . . . . . . . . . . . . .105Grigoriev, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Grigoriev, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Grigoriev, S.V. . . . . . . . . . . . . . . . . . . . . . . . . . . .30Grigorieva, N.A. . . . . . . . . . . . . . . . . . . . . . . . . . .30Grobert, N. . . . . . . . . . . . . . . . . . . . . . . . . . .53, 266Gronsky, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Gross, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Gross, S.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .36, 58Gross, T.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Grossmann, N. . . . . . . . . . . . . . . . . . . . . . . . . . .256Groven, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Grubb, J.F.* . . . . . . . . . . . . . . . . . . . . . . . . . . .54, 89Grylls, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259Gu, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81, 270Gu, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Gu, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Gu, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184, 247Guan, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Guan, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Guda Vishnu, K. . . . . . . . . . . . . . . . . . . . . . . . .147Guerra, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .237Guerra, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .237Guglielmino, E. . . . . . . . . . . . . . . . . . . . . . . . . .221Gugssa, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49Gulsoy, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Gumbsch, P. . . . . . . . . . . . . . . . . . . . . . . . . .12, 106Gunaydin, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .106Gunduz, I.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Guo, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Guo, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Guo, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235Guo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Guo, R. . . . . . . . . . . . . . . . . . . . . . . . . .6, 7, 36, 202Guo, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Guo, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125Gupta, M. . . . . . . . . . . . . . . . . . . . . . . . . . .130, 229Gupta, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Gupta, N.* . . . . . . . . . . . . . . . . . . . . . . . . .260, 272Gupta, P.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139Gupta, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193Gusman, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Gusman, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Guyer, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254

H

Ha, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Ha, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81Haake, J.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Haase, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .178Habel, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Haber, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Haber, R.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .159Habermeier, H.* . . . . . . . . . . . . . . . . . . . . . . . .104Hack, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Hae-Ryoung, K. . . . . . . . . . . . . . . . . . . . . . . . . . .17Hagihara, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Hahn, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Haider, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Haile, S.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110Halali, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226Halbig, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Hales, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108Hall, B.D. . . . . . . . . . . . . . . . . . . . . . . . . . . .40, 175Halloran, J.W. . . . .85, 132, 133, 141, 193, 194, 237Halloran, J.W.* . . . . . . . . . . . . . . . . . . . . . .193, 237Hamamoto, K. . . . . . . . . . . . . . . . . . . . . . .170, 171Hamann, J.A.* . . . . . . . . . . . . . . . . . . . . . . . . . .223Hamed Bahmanpour, H. . . . . . . . . . . . . . . . . .154Hamers, R.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Hamilton, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Hamming, L.M. . . . . . . . . . . . . . . . . . . . . . . . . . .87Hammond, C. . . . . . . . . . . . . . . . . . . . . . . . . . .159Hamza, A.V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Han, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .260Han, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80, 253Han, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Han, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Han, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Han, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Han, Y. . . . . . . . . . . . . . . . . . . . . . . . . .7, 17, 39, 60Hanaki, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242Hand, R.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Handa, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Haneda, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Hang, K.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Hanifi, A.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Hanke, L.* . . . . . . . . . . . . . . . . . . . . . . . . .178, 201Hanna, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .225Hanrahan, R.J.* . . . . . . . . . . . . . . . . . . . . . . . . .234Hansen, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Hansen, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Hansen, K.K. . . . . . . . . . . . . . . . . . . . . . . . . . . .171Hansen, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Hansen, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Hansford, B.E.* . . . . . . . . . . . . . . . . . . . . . . . . .241Haraguchi, N. . . . . . . . . . . . . . . . . . . . . . . . . . . .154Harbour, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Harden, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Hardwicke, C. . . . . . . . . . . . . . . . . . . . . . . . . . .183Hardy, J.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .198Harkness, J.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .58Harlow, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .148Harmer, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Harmer, M.P. . . . . . . . . . . . . . . . . .68, 76, 249, 267Harmer, M.P.* . . . . . . . . . . . . . . . . . . . . . . . . . .200Harringa, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Harris, R.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . .147Harrison, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Hartfield-Wunsch, S. . . . . . . . . . . . . . . . . . . . . .112Harth, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Harutyunyan, A. . . . . . . . . . . . . . . . . . . . . . . . . .42Harvey, S.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .217Hasanzade, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .253Hasegawa, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .157

Hashibon, A.* . . . . . . . . . . . . . . . . . . . . . . .12, 106Hashimoto, S. . . . . . . . . . . . . . . . . . . . . . . . . . .220Hashimura, M.* . . . . . . . . . . . . . . . . . . . . . . . . .121Hassan, H.A. . . . . . . . . . . . . . . . . . . . . . . . . .24, 28Hassini, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Hastings, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . .261Hata, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Hatchett, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Haugan, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Haugan, T.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Havelia, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .62, 166Havelia, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Hawley, M.E. . . . . . . . . . . . . . . . . . . . . . . . . . . .231Hayzelden, C.* . . . . . . . . . . . . . . . . . . . . . . . . . .248He, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38He, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202, 229He, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14, 263He, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91He, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .252He, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269He, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .171Headrick, W.L.* . . . . . . . . . . . . . . . . . . . . . . . . .189Heard, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Hebert, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Hebesberger, T. . . . . . . . . . . . . . . . . . . . . . . . . .188Hector, L.G. . . . . . . . . . . . . . . . . . . . . . . . .187, 188Heffelfinger, J. . . . . . . . . . . . . . . . . . . . . . . . . . .122Hefne, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49Heidari, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Hejtmanek, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .146Hellberg, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Heller, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Hellstrom, E.E. . . . . . . . . . . . . . . . . . . . . . . . . . . .17Helmick, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .238Hema, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Hemrick, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Heo, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Herderick, E.D.* . . . . . . . . . . . . . . . . . . . . . . . .196Herman, C.C.* . . . . . . . . . . . . . . . . . . . . . . . . . .169Herman, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Hernandez, D.H. . . . . . . . . . . . . . . . . . . . . . . . .122Hernández-Rodríguez, M. . . . . . . . . . . . . . . . .222Hernandez-Torres, J. . . . . . . . . . . . . .5, 24, 26, 261Heshmatimanesh, S. . . . . . . . . . . . . . . . . . . . . . .21Heuer, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .14, 157Heuer, A.H. . . . . . . . . . . . . . . . . . . . . .79, 184, 247Heuer, A.H.* . . . . . . . . . . . . . . . . . . . . . . . .47, 175Hibbard, G.D. . . . . . . . . . . . . . . . . . . . . . . . . . .250Hibbard, G.D.* . . . . . . . . . . . . . . . . . . . . . . . . . .250Hickel, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Hidalgo, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Highland, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . .116Higuchi, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Hill, D.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257Hilmas, G. . . . . . . . . . . . . . . . . . .30, 131, 132, 249Hilmas, G.E. . . . . . . . . . . . . . . . . . .31, 44, 132, 161Hilmas, G.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . .132Hilmi, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Hindler, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Hinkley, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .273Hinklin, T.R. . . . . . . . . . . . . . . . . . . . . . . .130, 239Hinz, W.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Hirano, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Hirao, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Hirayama, T. . . . . . . . . . . . . . . . . . . . . .69, 218, 246Hiroi, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Hirose, A. . . . . . . . . . . . . . . . . .61, 62, 89, 111, 134Hirsh, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Hiruma, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Hochauer, D. . . . . . . . . . . . . . . . . . . . . . . . . . . .266Hodgson, P.D. . . . . . . . . . . . . . . . . . . . .75, 80, 113

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 278

www.matscitech.org 279

Author Index

Hoel, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Hoffman, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . .265Hoffman, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .178Hoffmann, M.J. . . . . . . . . . . . . . . . . . . . . . . . . .224Hoffmann, M.J.* . . . . . . . . . . . . . . . . . . . . . . . .176Hojo, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Holc, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98, 204Holesinger, T.G. . . . . . . . . . . . . . . . . . . . . . . . . .231Holesinger, T.G.* . . . . . . . . . . . . . . . . . . . . . . . . .93Holgate, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Holt, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Holtappels, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Holton, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Holzer, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Honda, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Hong, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .7, 22, 256Hong, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203Hong, S. . . . . . . . . . . . . . . . . . . . . . . . . . .6, 80, 162Hong, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .14, 123Honjo, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Honkimaki, V. . . . . . . . . . . . . . . . . . . . . . . . . . .116Hoo, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Hoopes, P.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .254Hopkins, D. . . . . . . . . . . . . . . . . . . . . . . . . .43, 148Hopper, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Hopper, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .149Horne, D.H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Horton, R.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Hoshina, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Hosohara, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .220Hotta, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Hou, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121Houk, K.N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106House, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Hovanski, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . .133Hoveidamarashi, P. . . . . . . . . . . . . . . . . . . . . . .253Hovis, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Howard, K.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . .57Howe, J.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Howell, P.R.* . . . . . . . . . . . . . . . . . . . . . . . . .35, 57Hoyt, J.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Hrovat, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Hsieh, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Hsu, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Hu, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Hu, M.Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .159Hu, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Hu, S.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Hua, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Hua, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Huang, C. . . . . . . . . . . . . . . . . . . . . . . .3, 8, 67, 142Huang, C.* . . . . . . . . . . . . . . . . . . . . . . . . . .13, 156Huang, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212Huang, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Huang, Q. . . . . . . . . . . . . . . . . . . . . . .146, 203, 252Huang, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Huang, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Huang, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Huang, Y. . . . . . . . . . . . . . . . . . . . . . . . . .61, 65, 66Huang, Y.* . . . . . . . . . . . . . . . . . . . . .107, 259, 260Huang, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Hubbard, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Hubbard, J.B. . . . . . . . . . . . . . . . . . . . . . . . . . . .113Hubert, D.H. . . . . . . . . . . . . . . . . . . . . . . . . .41, 64Huey, B.D.* . . . . . . . . . . . . . . . . . . . .165, 186, 230Hughes, R.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Hulbert, D.M. . . . . . . . . . . . . . . . . . . . . . . . . . .219Hull, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107Hunger, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .222Hunt, M.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Hur, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .149

Hurley, M.F. . . . . . . . . . . . . . . . . . . . . . . . .158, 206Husakova, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Huse, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Hussain, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Hussain, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23Husseini, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Hussin, R. . . . . . . . . . . . . . . . . . . . . . . . . . .167, 205Huth, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Hutter, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Hwang, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79Hwang, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Hwang, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248Hwang, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130Hwang, J.Y. . . . . . . . . . . . . . . . . . . . . . . . . .249, 271Hwang, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Hyuga, H. . . . . . . . . . . . . . . . . . . . . . . . . . .208, 237

I

I. Espitia-Cabrera, I. . . . . . . . . . . . . . . . . . . . . .159Ibberson, R.M.* . . . . . . . . . . . . . . . . . . . . . . . . . .46Ibrahim, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Ice, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Ice, G.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Ice, G.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67, 77Ichinose, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .141Idalgo, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28Iddir, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Ide, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61, 62Idrobo, J.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Iijima, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Iiyama, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Ikariyama, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Ikeda, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Ikeda, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Ikuhara, Y. . . . . . . . . . . . . . . . . . . . . . . . . . .69, 246Ikuhara, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Ikuhara, Y.H.* . . . . . . . . . . . . . . . . . . . . . . . . . .218Iliescu, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .186Im, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81, 253Imam, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Imanaka, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Imbrie, P.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .186Imrich, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Imrich, K.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Ingram, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Iñiguez-Sánchez, C.A.* . . . . . . . . . . . . . . . . . . . .83Inoue, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .62, 212Inoue, J. . . . . . . . . . . . . . . . . . . . . . . . . .90, 91, 112Inoue, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Ionescu, R.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . .22Ioppolo, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .260Iqbal, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .206Iqbal, S.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Irby, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Irina, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Irissou, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255Isaacs, E.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Isaacs, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236Ishihara, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Ishihara, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Ishikawa, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Ishikawa, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .198Ishimoto, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . .112Ishiwata, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Islam, M.* . . . . . . . . . . . . . . . . . . . . . . . .40, 43, 217Islam, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Ismer, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Ito, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10, 144Itoh, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154Itsuno, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154

Ivanov, V.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .238Ivar, R.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Iwai, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Iwanaga, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Iwasawa, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .232Iwatani, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Iyengar, R.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Izui, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28, 271Izui, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200

J

Jackson, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Jackson, A.G. . . . . . . . . . . . . . . . . . . . . . . . . . . .196Jackson, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212Jackson, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Jackson, T.N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Jackson, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Jacques, C. . . . . . . . . . . . . . . . . . . . . . . . . .187, 243Jain, F.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Jain, G.H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Jain, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Jain, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233Jain, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19Jain, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Jain, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Jakabsky, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Jakus, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250Jalilian, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249James, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Jamison, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65Jamnik, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17Jancar, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Jang, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Jang, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Jang, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Jang, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Janssens, K.G.* . . . . . . . . . . . . . . . . . . . . . . . . . .148Jansto, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Jansto, S.G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Jantzen, C.M.* . . . . . . . . . . . . . . . . . . . . . . .99, 265Jaouen, M. . . . . . . . . . . . . . . . . . . . . . . . . . .85, 181Jaques, A.V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .183Jaques, B.J.* . . . . . . . . . . . . . . . . . . . . . . . .158, 206Jauhari, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Jayasinghe, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .81Jean, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Jebaraj, M.p. . . . . . . . . . . . . . . . . . . . . . . . . . . . .229Jeedigunta, H. . . . . . . . . . . . . . . . . . . . . . . . . . .197Jeevan Kumar, D.* . . . . . . . . . . . . . . . . . . . . . . .261Jellison, G.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Jenekhe, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Jeniski, R.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90Jenkins, C.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Jenner, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Jennings, H.M. . . . . . . . . . . . . . . . . . . . . . . . . . . .84Jeon, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22Jeon, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Jeong, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Jeong, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Jerebtsov, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Jernkvist, L.O. . . . . . . . . . . . . . . . . . . . . . . . . . .116Jesse, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Jha, B.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Jha, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242, 245Jha, S.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108Jha, S.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .43, 71Jia, Q. . . . . . . . . . . . . . . . . . . . .59, 62, 95, 262, 264Jia, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Jia, Q.X. . . . . . . . . . . . . . . . . . . . . . . . . . . .231, 233Jiang, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 279

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania280

Author Index

Jiang, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Jiang, J. . . . . . . . . . . . . . . . . . . . . . . . . .36, 166, 263Jiang, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .202, 229Jiang, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167Jiang, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .183Jiang, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .224, 259Jiang, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167Jiang, Y. . . . . . . . . . . . . . . . . . . . . . . . .207, 234, 235Jiang, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121Jiao, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Jie, Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Jie, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Jiménez, J.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Jin Woo, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Jin, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22Jin, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Jin, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46, 81Jin, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .235, 271Jitianu, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .271Jitianu, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Jitianu, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .159Jo, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Jo, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Jochum, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Jochum, T.W. . . . . . . . . . . . . . . . . . . . . . . . . . . .161Johannes, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .88John, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71, 245John, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .245John, V.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Johnson, A.A.* . . . . . . . . . . . . . . . . . . . . . . .70, 108Johnson, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Johnson, C. . . . . . . . . . . . . . . . . . . . . . . . . .207, 234Johnson, C.D. . . . . . . . . . . . . . . . . . . . . . . . . . . .235Johnson, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Johnson, D.D. . . . . . . . . . . . . . . . . . . . . . . .183, 218Johnson, D.D.* . . . . . . . . . . . . . . . . . . . . . . . . . .147Johnson, J.* . . . . . . . . . . . . . . . . . . . . . . . .113, 145Johnson, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Johnson, M.T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .88Johnson, R. . . . . . . . . . . . . . . . . . . . . . . . . . .39, 111Johnson, S.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Johnson, S.M.* . . . . . . . . . . . . . . . . . . . . . . . . . .131Jokisaari, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .222Jonas, J.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Jones, J. . . . . . . . . . . . . . . . . . . . . . . . . . .4, 178, 212Jones, J.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Jones, J.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94Jones, J.W. . . . . . . . . . . . . . . . . . . . . . . . . . .108, 212Jones, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236Jono, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172Joo, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22, 29Jordan, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Jorge-Badiola, D. . . . . . . . . . . . . . . . . . . . . . . . .118Jorger, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Joseph, I. . . . . . . . . . . . . . . . . . . . . . . . . . . .143, 170Joseph, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Joshi, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Joshi, S.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Joulain, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137Jud Sierra, E. . . . . . . . . . . . . . . . . . . . . . . . . . . .173Jud Sierra, E.* . . . . . . . . . . . . . . . . . . . . . . . .69, 173Jud, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Judson, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Judy, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Jue, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Juenger, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125Juenger, M.* . . . . . . . . . . . . . . . . . . . . . . . . .63, 124Juhas, M.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133Jun, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81Jung, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16Jung, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65

Jung, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10, 29Jung, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .149, 162Jung, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Jung, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226Jung, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110Jung, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81Junliang, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Jur, T.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .147Jurczyk, M.U.* . . . . . . . . . . . . . . . . . . . . . . . . . .101Jurgensen, A.R. . . . . . . . . . . . . . . . . . . . . . . . . .265Jurkschat, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .266

K

K Hasanain, S. . . . . . . . . . . . . . . . . . . . . . . . . . .231Kadlec, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Kadokura, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .223Kaduk, J.A. . . . . . . . . . . . . . . . . . . . . . . . . .146, 203Kagawa, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . .74, 160Kagawa, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Kahler, D. . . . . . . . . . . . . . . . . . . . . . .128, 182, 268Kahn, H. . . . . . . . . . . . . . . . . . . . . . . . .47, 184, 247Kahn, L.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Kahvecioglu, O.* . . . . . . . . . . . . . . . . . . . . . . . .144Kaiser, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235Kakiuchi, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Kalay, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Kalinin, S.V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Kalinin, S.V.* . . . . . . . . . . . . . . . . . . . . . . . . . . .185Kalita, S.J.* . . . . . . . . . . . . . . . . . . .23, 28, 222, 254Kamat, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54Kamba, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Kamehara, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . .60Kamf, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Kamikawa, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Kamo, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Kanakala, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .226Kane, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233Kane, M.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39Kane, R.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Kane, W.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .164Kaneko, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Kang, B.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235Kang, B.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .206Kang, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81Kang, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .270Kang, J.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218Kang, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Kang, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .33, 244Kang, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22Kang, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74Kang, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .81, 187Kang, S.L. . . . . . . . . . . . . . . . . . . . . . . . . . . .43, 239Kang, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Kaniuk, J.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Kanner, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Kao, C.* . . . . . . . . . . . . . . . . .89, 98, 205, 250, 257Kaplan, W.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Kaplan, W.D.* . . . . . . . . . . . . . . . . . . . . . . . . . .164Karan, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Karan, N.K. . . . . . . . . . . . . . . . . . . . . . . . . . . .5, 7, 9Karbasian, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . .48Kareliya, C.H.* . . . . . . . . . . . . . . . . . . . . . . . . . .273Karelova, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .188Karlsdottir, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .132Karmarkar, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .59Karnesky, R.A. . . . . . . . . . . . . . . . . . . . . . . . . . .183Karnezos, T.C.* . . . . . . . . . . . . . . . . . . . . . . . . . .79Karumuri, A.* . . . . . . . . . . . . . . . . . . . . . . . . . .256Kasimatis, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Kasinath, R.K.* . . . . . . . . . . . . . . . . . . . . . . . . .159

Katayama, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .206Kathrein, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Katiyar, R. . . . . . . . . . . . . . . . . . . . . . . .3, 5, 40, 166Katiyar, R.S. . . . . . . . . . . . . . . . . . .5, 7, 9, 203, 205Katiyar, R.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .262Kato, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Kato, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .168, 203Katsuki, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Kattner, U.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .100Kaur, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Kaur, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Kaushik, B.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Kavaipatti, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Kavaipatti, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . .65Kavlicoglu, B. . . . . . . . . . . . . . . . . . . . . . . . . . . .257Kawada, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .110Kawahara, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .172Kawahara, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .220Kawamura, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Kawamura, K. . . . . . . . . . . . . . . . . . . . . . . . . . .263Kawasaki, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .52Kayihan, A.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Kayukawa, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .203Kazal, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Ke, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Ke, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Keane, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Kear, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Kearley, G.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52Kecskes, L.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Keefe, M.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Keefe, T.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Keel, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .171Keicher, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259Keiser, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Keiser, D.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Keiser, D.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Kelkar, D.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Kell, J.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Kell, J.W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Kelley, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Kelley, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Kelsey, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Kempa, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Kennedy, M.S.* . . . . . . . . . . . . . . . . . . . . .164, 268Kennedy, R.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . .90Kennedy, Z.E.* . . . . . . . . . . . . . . . . . . . . . . . . . .273Kerscher, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Keshmiri, H. . . . . . . . . . . . . . . . . . . . . . . . .252, 253Keto, J.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232Ketsuwan, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Key, T.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Khachaturyan, A. . . . . . . . . . . . . . . . . . . . . .44, 139Khachaturyan, A.G. . . . . . . . . . . . . . . . . . . . .59, 94Khalifah, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Khalili, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208Khan, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Khan, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Khan, M.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19Khan, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Khan, U. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Kharche, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .176Kharlamova, M. . . . . . . . . . . . . . . . . . . . . . .27, 225Kholkin, A.I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95Khoruzha, V.G. . . . . . . . . . . . . . . . . . . . . . . . . . . .7Khosla, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214Khouri, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208Kieffer, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .125, 195Kieffer, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Kiely, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . .15, 192Kiely, C.J. . . . . . . . . . . . . . . . . . . . . . . . . . .249, 267

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 280

www.matscitech.org 281

Author Index

Kiilunen, W.D. . . . . . . . . . . . . . . . . . . . . . . . . . .135Kikuchi, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Kim, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .172, 209Kim, C. . . . . . . . . . . . . . . . . . .26, 45, 127, 140, 143Kim, D. . . . . . . . . . . . . . . .4, 20, 63, 74, 80, 85, 261Kim, D.* . . . . . . . . . . . . . . . . . . . . . .22, 25, 32, 169Kim, D.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Kim, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Kim, G.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Kim, H.4, 7, 17, 18, 27, 29, 33, 36, 48, 53, 101, 139,

161, 169Kim, H.* . . . . . . . . . . . . . . . . . .4, 7, 20, 74, 96, 245Kim, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36, 253Kim, J. . . . . . . . . . . . . . . . . . . .6, 144, 195, 243, 253Kim, J.* . . . . . . . . . . . . . . . . . . . . . .17, 22, 119, 169KIm, J.h. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .245Kim, J.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .245Kim, J.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .217Kim, J.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .198Kim, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Kim, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .7, 25, 129Kim, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22Kim, S. . . .22, 32, 33, 43, 72, 74, 79, 165, 221, 244Kim, S.* . . . . . . . . . . . . .26, 34, 43, 80, 81, 244, 257Kim, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22, 24Kim, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Kim, Y. . . . . . . . . . . . . . . . . . . . . . . . .18, 24, 27, 29Kim, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .21, 251Kiminami, R.H. . . . . . . . . . . . . . . . . . . . . . . . . . .97Kimura, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Kimura, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85Kimura, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91Kimura, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Kimura, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Kimura, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209King, D.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82King, D.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .197King, M.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .149King, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Kirchheim, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Kirihara, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Kirihara, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Kirill, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Kirsch, M.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Kisa, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Kishi, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Kislitsyn, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Kita, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208Kita, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . .236, 237Kiyota, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Klarstrom, D. . . . . . . . . . . . . . . . . . . . . . . . . . . .134Klein, L.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .271Kleinke, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Klepper, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Kliber, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Klie, R.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .69, 117Klie, R.F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233Klimeck, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .176Klingbeil, N.W. . . . . . . . . . . . . . . . . . . . . . . . . . .54Klotz, U.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Kneissl, A.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .112Knickerbocker, J.U.* . . . . . . . . . . . . . . . . . . . . . .56Knipling, K.E.* . . . . . . . . . . . . . . . . . . . . . . . . . .249Knirsch, J.* . . . . . . . . . . . . . . . . . . . . . . . . .135, 138Knott, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Knowles, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Knox, V.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Knuteson, D. . . . . . . . . . . . . . . . . . . .128, 182, 268Knyazev, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Ko, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .252Ko, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161

Kobayashi, K. . . . . . . . . . . . . . . . . . . . . . . . . . .8, 72Kobayashi, K.F. . . . . . . . . . . . . . . . . . . . . . . . . . . .89Kobayashi, M. . . . . . . . . . . . . . . . . . . . . . . .78, 241Kobayashi, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Kobelev, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Koc, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54, 188Koch, C.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .152Kodama, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Kodambaka, S.* . . . . . . . . . . . . . . . . . . . . . . . . .238Kodera, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Kodera, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Kogel, L.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .149Koike, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Kokkinos, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Kolesnik, I.* . . . . . . . . . . . . . . . . . . . . . . . . .27, 225Komarneni, S.* . . . . . . . . . . . . . . . . . . . . . . . . .128Komarov, F. . . . . . . . . . . . . . . . . . . . . . . . . . .12, 25Komeya, K. . . . . . . . . . . . . . . . . . . . .5, 29, 208, 225Komolwit, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . .153Komotori, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Kondo, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .237Kondo, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Kondo, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170König, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Kontsevoi, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Kontsevoi, O.Y.* . . . . . . . . . . . . . . . . . . . . . . .14, 15Koo, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Koo, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Koo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .33, 34, 244Kornyei, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Korolev, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Kosec, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Kosec, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Koseki, T. . . . . . . . . . . . . . . . . . . . . . . . .90, 91, 112Kostarelos, K. . . . . . . . . . . . . . . . . . . . . . . .154, 254Kostov, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Kot, W.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Kothleitner, G. . . . . . . . . . . . . . . . . . . . . . . . . . .218Kotov, N.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Kotula, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Koumoto, K. . . . . . . . . . . . . . . . . . . . . . . . .104, 246Kounga, A.B. . . . . . . . . . . . . . . . . . . . . . . . . . . .231Koushyar, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .79Kovacevic, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .260Kovacova, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Kovar, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232Kovarik, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Kozuka, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Kraaijenbos, F. . . . . . . . . . . . . . . . . . . . . . . . . . .219Kracher, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Kral, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Kral, M.V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Kramer, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Kramer, M.J. . . . . . . . . . . . . . . . . . . . .157, 198, 226Krane, M. . . . . . . . . . . . . . . . . . . . . . . . . . .126, 127Krauss, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79Krempaszky, C. . . . . . . . . . . . . . . . . . . . . . . . . .188Krishnamurthy, K. . . . . . . . . . . . . . . . . . . . . . . . .86Krishnan, S. . . . . . . . . . . . . . . . . . . . . . . . . .14, 121Krishnan, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .121Krivoruchko, A.V. . . . . . . . . . . . . . . . . . . . . . . . .33Kruft-Steuler, B. . . . . . . . . . . . . . . . . . . . . . . . . .256Krug, M.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247Kruger, A.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Krugljak, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Krumpelt, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Kuang, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Kubaski, E.T.* . . . . . . . . . . . . . . . . . . . . . . . .31, 229Kuforiji, C.U. . . . . . . . . . . . . . . . . . . . . . . . . . . .136Kugel, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Kuhn, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

Kujur, M.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Kulkarni, N.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .76Kulwant Singh, T. . . . . . . . . . . . . . . . . . . . . . . .204Kuma, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .229Kumagai, T. . . . . . . . . . . . . . . . . . . . . . . .4, 39, 170Kumah, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Kumar, A. . . . . . . . . . . . . . . . . . . . . .9, 40, 101, 197Kumar, A.* . . . . . . . . . . . . . . . . . . . . . . .3, 203, 205Kumar, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .25, 51Kumar, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Kumar, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19Kumar, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135Kumar, S.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Kumar, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Kumbeeshwar, M. . . . . . . . . . . . . . . . . . . . . . . .263Kumta, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Kundig, K.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .54Kuo, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Kupchishin, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .25Kuramoto, T. . . . . . . . . . . . . . . . . . . . . . . . . . . .219Kurapati, S.N.* . . . . . . . . . . . . . . . . . . . . . . . . . .150Kurihara, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Kuroishi, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .206Kurosaki, K. . . . . . . . . . . . . . . . . . . . . .10, 144, 206Kurosaki, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .206Kurtis, K.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Kuscer, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Kusunose, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Kuwata, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Kuzel, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Kwak, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81, 253Kwon, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Kwon, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . .32, 135

L

La Robina, M. . . . . . . . . . . . . . . . . . . . . . . . .9, 143Laabs, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98LaCombe, J.C.* . . . . . . . . . . . . . . . . . . . . . . . . .183Lagenaur, C.F. . . . . . . . . . . . . . . . . . . . . . . . . . .190Lagerlof, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14LaGrange, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .217Lahrman, D. . . . . . . . . . . . . . . . . . . . . . . . .244, 245Lai, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212Lai, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Laine, R.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .129Laird, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236Laister, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Lakeman, C.D. . . . . . . . . . . . . . . . . . . . . . . . . . .101Lam, T.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Lance, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Lancellotti, I. . . . . . . . . . . . . . . . . . . . . . . . . .9, 143Landes, J.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .108Lange, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .155Lange, F.F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94Langhorst, B.* . . . . . . . . . . . . . . . . . . . . . . . . . .250Laplanche, G. . . . . . . . . . . . . . . . . . . . . . . . . . . .137Lara-Curzio, E. . . . . . . . . . .101, 161, 175, 209, 212Larbalestier, D. . . . . . . . . . . . . . . . . . . . . . . . . . . .93Larbalestier, D.C. . . . . . . . . . . . . . . . . . . . . . . . . .17Larkin, C.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Larsen Werchmeister, R.M. . . . . . . . . . . . . . . . .171Larsen, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .242, 245Larsen, J.M. . . . . . . . . . . . . . . . . . . . . . .43, 71, 108Larson, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Latiff, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Lau, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Lavernia, E.J. . . . . . . . . . . . . . . .135, 136, 219, 256Law, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Lawless, B.H. . . . . . . . . . . . . . . . . . . . . . . . . . . .179Lawson, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 281

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania282

Author Index

Lazar, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Le Gall, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238Le Gall, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Leal-Cruz, A.L. . . . . . . . . . . . . . . . . . . . . . . .30, 161Lebeau, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Lebedev, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Lechler, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Lechler, J.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Lederich, R.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .42Lee, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Lee, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102, 119Lee, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79Lee, H. . . . . . . . . . . . . . . . .7, 63, 162, 172, 209, 229Lee, J. . . . . . . . . . . . . . .4, 32, 62, 135, 172, 203, 253Lee, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65Lee, J.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Lee, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22, 24Lee, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81Lee, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Lee, S. . . . . . . . . . . . . .4, 6, 20, 24, 79, 81, 187, 243Lee, S.* . . . . . . . . . . . . . . . . . .17, 47, 187, 207, 213Lee, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Lee, W. . . . . . . . . . . . . . . . . . . . . . . . . . . .33, 34, 96Lee, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3Lee, Y. . . . . . . . . . . . . . . . . . . . .32, 81, 96, 119, 135Lee, Y.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Legoux, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255Leidolph, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . .225Lein, H.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Leinenbach, C. . . . . . . . . . . . . . . . . . . . . . . . . . .216Leinenbach, C.* . . . . . . . . . . . . . . . . . . . . . . . . .223Leist, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Lekakh, S.N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .270Lemieux, T.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Lemmens, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Leonelli, C.* . . . . . . . . . . . . . . . . . . . . . . . . . .9, 143León-Mancilla, B. . . . . . . . . . . . . . . . . . . . . . . . .23Lerch, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67LeSar, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Leshchinsky, E. . . . . . . . . . . . . . . . . . . . . . . .26, 255Leshchinsky, E.* . . . . . . . . . . . . . . . . . . . . . . . . .255Leshchynsky, V. . . . . . . . . . . . . . . . . . . . . . . . . .228Lespinasse, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Leung, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Levchenko, E.V. . . . . . . . . . . . . . . . . . . . . . . . . . .76Levi, R.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Levin, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39Levy, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Lewandowski, J. . . . . . . . . . . . . . . . . . . . . .126, 156Lewandowski, J.* . . . . . . . . . . . . . . . . . . . . . . . .200Lewandowski, J.J. . . . . . . . . . . . . . . . . . .33, 36, 156Lewandowski, J.J.* . . . . . . . . . . . . . . . . . . . . .24, 28Lewinsohn, C.A.* . . . . . . . . . . . . . . . . . . . . . . .191Lewis, A.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .210Lewis, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .98, 167Lewis, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . .65, 238Lewis, S.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .272Ley, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Leyma, R.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Li, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116, 164Li, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98, 269Li, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Li, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160, 214Li, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Li, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .25, 106, 161Li, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84, 238Li, H.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70Li, J. . . . . . . . . . . . . . . . . . . . . . .29, 38, 95, 138, 251Li, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Li, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196Li, L. . . . . . . . . . . . . . . . . . .183, 234, 259, 260, 268

Li, L.* . . . . . . . . . . . . . . . . . . . . .134, 218, 235, 260Li, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Li, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37, 61Li, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Li, Q. . . . . . . . . . . . . . . . . . . . . . . . . . .146, 175, 209Li, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205, 264Li, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28Li, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Li, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . .76, 93, 197Li, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214Li, Y. . . . . . . . . . . . . . . . .86, 95, 136, 215, 258, 262Li, Y.* . . . . . . . . . . . . . . . . . . . . .38, 59, 95, 201, 207Li, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Li, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3Lian, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Liang, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Liang, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Liang, S.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .245Liang, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Liang, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Liao, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .22, 269Liaw, P.K.* . . . . . . . . . . . . . . . . . . . . . . . . .212, 241Lienert, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259Lienert, U. . . . . . . . . . . . . . . . . . . . . . . . . .116, 244Lim, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .270Lim, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81Lin, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202Lin, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Lin, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Lin, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .260Lin, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Lin, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Lin, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Lin, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Lin, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Lindemer, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .39Link, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28Link, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Lippold, J.C. . . . . . . . . . . . . . . . . . . . . . . . .133, 228Lisi, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Litzelman, S.J. . . . . . . . . . . . . . . . . . . . . . . . . . .110Litzelman, S.J.* . . . . . . . . . . . . . . . . . . . . . . . . . .72Liu, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40, 213Liu, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47, 116Liu, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259Liu, D.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Liu, G. . . . . . . . . . . . . . .15, 105, 146, 157, 203, 253Liu, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6, 65Liu, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .270Liu, J. . . . . . . . . . . . . . . . .36, 54, 122, 147, 202, 229Liu, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166, 202Liu, J.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Liu, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Liu, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16Liu, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84, 149Liu, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Liu, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227, 241Liu, W. . . . . . . . . . . . . . . . . . . . . . . . . .77, 151, 243Liu, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172Liu, X. . . . . . . . . . . . . . . . . . .37, 113, 207, 234, 235Liu, Y. . . . . . . . . . . . . . . . . . . .8, 156, 223, 257, 260Liu, Z. . . . . . . . .16, 19, 32, 65, 66, 86, 95, 103, 151,

207, 217, 246, 247Liu, Z.* . . . . . . . . . . . . . . . . . . . .114, 164, 176, 181Livingston, R.A. . . . . . . . . . . . . . . . . . . . . . . . . . .50Ljiljana, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . .3, 138LLorca, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55Lloyd, I.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141Lo, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Loeffler, J.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Loehman, R.E. . . . . . . . . . . . . . . . . . . . . . . . . . . .88

Logan, K.V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Löhe, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Loif, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Lombardo, S.J. . . . . . . . . . . . . . . . . . . . . . . . . . .141Lombardo, S.J.* . . . . . . . . . . . . . . . . . . . .85, 86, 93Lomeli, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Lomonaco, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .186Long, T.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Longanbach, S. . . . . . . . . . . . . . . . . . . . . . . . . . .248Longo, D.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Lopes, E.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Lopez, M.I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Lopez-Hirata, V.M. . . . . . . . . . . . . . . . . . . .75, 246Lorenz, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202Losego, M.D.* . . . . . . . . . . . . . . . . . . . . . . . . . .230Loudis, J.A. . . . . . . . . . . . . . . . . . . . . . . . . .225, 254Louet, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Løvvik, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Lowhorn, N. . . . . . . . . . . . . . . . . . . . . . . . .146, 203Lowney, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19Lu, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Lu, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172Lu, G.X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70Lu, K. . . . . . . . . . . . . . . . . . . . . . . . . .172, 259, 260Lu, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .129, 159Lu, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114, 252Lu, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Lu, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103, 214Lubrick, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255Lubrick, M.A.* . . . . . . . . . . . . . . . . . . . . . . . . . .228Lucas, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .186, 230Ludwig, D.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Lukashin, A. . . . . . . . . . . . . . . . . . . . . . . . . .27, 225Lukashin, A.V. . . . . . . . . . . . . . . . . . . . . . . . . . . .30Lund, A.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Luo, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Luo, J. . . . . . . . . . . . . . . . . . . . . . . . . . .15, 180, 230Luo, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Luo, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Lushnikov, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .203Luz, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Luzinov, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Lynn, A.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Lyszyk, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

M

Ma, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Ma, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Ma, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139Ma, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .147Ma, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Ma, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Ma, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Ma, Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Ma, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Ma, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Ma, Y.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Ma, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Macdonald, D.D.* . . . . . . . . . . . . . . . . . . . .45, 144Maciejewski, K.* . . . . . . . . . . . . . . . . . . . . . . . .188MacKenzie, K.J. . . . . . . . . . . . . . . . . . . . . . . . . .173Mackert, J.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .222MacManus-Driscoll, J. . . . . . . . . . . . . . . . . . . .264MacManus-Driscoll, J.L. . . . . . . . . . . . . . . .62, 168MacPherson, R.D. . . . . . . . . . . . . . . . . . . . . . . . .68Madej, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . .75, 113Madtha, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Maekawa, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .206Maev, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .26, 228Maev, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 282

www.matscitech.org 283

Author Index

Maeva, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255Magee, E.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Magnin, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Mahabunphachai, S.* . . . . . . . . . . . . . . . . . . . . .54Mahajan, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .139Mahapatra, M. . . . . . . . . . . . . . . . . . . . . . . . . . .260Mahapatra, M.* . . . . . . . . . . . . . . . . . . . . . . . . .172Mahdak, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249Mahna, S.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Maier, J. . . . . . . . . . . . . . . . . . . . . . . . . . .17, 44, 180Maiorov, B. . . . . . . . . . . . . . . . . . . . . . . . . . .93, 264Maiti, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156Majérus, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Majidi, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .178Majumdar, P. . . . . . . . . . . . . . . . . . . . . . . . . . . .190Majzoub, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .107Makeev, M.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .88Malek Ghaini, F. . . . . . . . . . . . . . . . . . . . . . . . . . .31Malgerejo, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Mallick, K.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .82Mallik, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Maloy, S.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227Maly, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Manabe, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Mandal, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Manea, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Manga, V.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Maniruzzaman, M. . . . . . . . . . . . . . . . . . . . . . . .79Manisha, T.* . . . . . . . . . . . . . . . . . . . . . . . . .10, 102Manlapaz, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Manna, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194Mannava, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .244Mannava, S.R. . . . . . . . . . . . . . . . . . .244, 245, 247Mannhart, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Mansourian-Hadavi, N. . . . . . . . . . . . . . . . . . .146Manthiram, A.* . . . . . . . . . . . . . . . . . . . . . .65, 142Mantina, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .19Mao, S.X.* . . . . . . . . . . . . . . . . . . . . . . . . .111, 152Mao, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .210Marandian-Hagh, N. . . . . . . . . . . . . . . . . . . . . .140Marashi, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31Marathe, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . .184Marchal, J.C. . . . . . . . . . . . . . . . . . . . . . . . . . . .129Marchev, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Marcus, H.L. . . . . . . . . . . . . . . . . . . . . . . . . . . .249Marder, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Margetts, L. . . . . . . . . . . . . . . . . . . . . . . . . .16, 211Maria, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Maritato, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Mark, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139Mark, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Maroni, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93Marques, G.A.* . . . . . . . . . . . . . . . . . . . . . . . . .112Marquis, E.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Marra, J.* . . . . . . . . . . . . . . . . . . . . . . . . . .233, 234Marra, J.C. . . . . . . . . . . . . . . . . . . .8, 142, 143, 170Marschall, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31Martens, R.L. . . . . . . . . . . . . . . . . . . . . . . . . . . .246Martin, F.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Martin, L.W.* . . . . . . . . . . . . . . . . . . . . . . . . . . .232Martin, M. . . . . . . . . . . . . . . . . . . . . . . . . .227, 257Martinez, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Martinez, E.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . .122Martinez, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Martins, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Marvel, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .272Marx, B.M. . . . . . . . . . . . . . . . . . . . . . . . . .158, 206Marzari, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107Masaki, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Masek, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Mason, D.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .151

Mason, T.O. . . . . . . . . . .44, 72, 146, 149, 213, 217Massih, A.R.* . . . . . . . . . . . . . . . . . . . . . . .114, 116Matias, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Matlack, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Matlack, K.S. . . . . . . . . . . . . . . . . . . . . . . . . . . .143Matlock, D.K. . . . . . . . . . . . . . . . . . . . . . . . . . . .119Matsui, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Matsumiya, M. . . . . . . . . . . . . . . . . . . . . . . . . . .172Matsumoto, H. . . . . . . . . . . . . . . . . . . . . . . . . . .243Matsumoto, K. . . . . . . . . . . . . . . . . . . . . . . . . . .243Matsumoto, S. . . . . . . . . . . . . . . . . . . . . . . . . . .265Matsumura, K. . . . . . . . . . . . . . . . . . . . . . . . . . .160Matsumura, K.* . . . . . . . . . . . . . . . . . . . . . . . . .160Matsumura, T. . . . . . . . . . . . . . . . . . . . . . . . . . .109Matsuo, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Matsuura, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .251Matteis, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Maudlin, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107Maupin, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Maurer, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23May, A.F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208Mayer, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49Mayer, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Mayhew, K.M. . . . . . . . . . . . . . . . . . . . . . . . . . . .64Mazen, A.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .273Maziasz, P.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .217Mazjoub, E.H. . . . . . . . . . . . . . . . . . . . . . . . . . .106Mazumder, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .259McCallum, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .139McCartney, G.D. . . . . . . . . . . . . . . . . . . . . . . . . .53McCauley, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .34McClarnon, D. . . . . . . . . . . . . . . . . . . . . . . . . . .128McClellan, K.J. . . . . . . . . . . . . . . . . . . . . . . . . . .205McClellan, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .82McCleskey, T. . . . . . . . . . . . . . . . . . . . . . . . . . . .231McClung, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .242McCombs, M.F. . . . . . . . . . . . . . . . . . . . . . . . . .168McConnell, R. . . . . . . . . . . . . . . . . . . . . . . . . . .256McCoy, T.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .250McCrabb, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .25McCrabb, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .51McDermid, J.R. . . . . . . . . . . . . . . . . . . . . . . .22, 47McDowell, D.L. . . . . . . . . . . . . . . . . . . . . .239, 242McDowell, D.L.* . . . . . . . . . . . . . . . . . . . . .13, 241McEligot, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82McGarry, D.* . . . . . . . . . . . . . . . . . . . . . . . . .42, 71McGaughey, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .15McGee, H. . . . . . . . . . . . . . . . . . . . . . . .65, 98, 238McGowan, K.A. . . . . . . . . . . . . . . . . . . . . . . . . .270McGrail, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99McGrath, M.C.* . . . . . . . . . . . . . . . . . . . . . . . . .270McGuffin-Cawley, J.D.* . . . . . . . . . . . . . . . . . .180McKindra, T.* . . . . . . . . . . . . . . . . . . . . . . . . . .245McLaughlin, S. . . . . . . . . . . . . . . . . . .128, 182, 268McLean, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250McMeeking, R.M. . . . . . . . . . . . . . . . . . . . . . . .126McNulty, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Meacham, B.E. . . . . . . . . . . . . . . . . . . . . . .135, 271Meador, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167Meador, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Mebane, D.S.* . . . . . . . . . . . . . . . . . . . . . . .16, 180Mecartney, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .13Mecartney, M.L. . . . . . . . . . . . . . . . . . . . . . . . . . .66Medellín-Rodríguez, F.J. . . . . . . . . . . . . . . . . . .261Medina, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Medraj, M. . . . . . . . . . . . . . . . . . . . . . . . . . .19, 217Medvedovski, E.* . . . . . . . . . . . . . . . . . . . . . . . .224Meese, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .186Meguro, T. . . . . . . . . . . . . . . . . . . . . . . . .5, 29, 208Mehl, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49, 82Mehrabi, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .112

Meier, A.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Meier, G.H. . . . . . . . . . . . . . . . . . . . . . .15, 127, 144Mejía de Gutierrez, R. . . . . . . . . . . . . . . . . . . . .155Meleshevich, K.A. . . . . . . . . . . . . . . . . . . . . . . . . .7Meletis, E. . . . . . . . . . . . . . . . . . . .36, 202, 229, 263Meletis, E.I. . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Melo-Maximo, D.V.* . . . . . . . . . . . . . . . . . .75, 246Men, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Mendes, L.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31Méndez Martín, F. . . . . . . . . . . . . . . . . . . . . . . .115Mendez Martin, F. . . . . . . . . . . . . . . . . . . . . . . .218Mendez Martin, F.* . . . . . . . . . . . . . . . . . . . . . .218Mendoza-Galvan, A. . . . . . . . . . . . . . . . . . . . . . .26Menéndez, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Meng, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70Meng, X.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Menon, A.K. . . . . . . . . . . . . . . . . . . . . . . . . .28, 222Menon, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Menon, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .171Menzer, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172Mercier, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Mercioniu, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Merkle, B.D. . . . . . . . . . . . . . . . . . . . . . . . .135, 271Merkle, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .180Merklein, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Merklein, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Merzkirch, M.J.* . . . . . . . . . . . . . . . . . . . . . . . .136Mesoravic, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .111Messersmith, P.B. . . . . . . . . . . . . . . . . . . . . . . . . .87Messing, G. . . . . . . . . . . . . . . . . . . . . . . . . . . .60, 85Messing, G.L. . . . . . . . . . . . . . . . . . . . . . . . . .36, 86Mettupalayam, B.* . . . . . . . . . . . . . . . . . . . . . . .193Metwalli, M.A. . . . . . . . . . . . . . . . . . . . . . . . . . .273Meyer, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Meyer, R.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Mi, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Miao, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212Michal, G.M. . . . . . . . . . . . . . . . . . . . . . . . .47, 184Michal, G.M.* . . . . . . . . . . . . . . . . . . . .46, 79, 247Michiuchi, M. . . . . . . . . . . . . . . . . . . . . . . .91, 112Michiuchi, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .90Mierzwa, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Mihaila, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Miki, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Mikula, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Miles, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133Miles, R.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Militzer, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Miller, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93Miller, D.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .181Miller, H.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Miller, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Miller, M.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .159Miller, M.P.* . . . . . . . . . . . . . . . . . . . . . . . . .71, 116Miller, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Miller, T.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .155Millett, S.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .238Mills, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Mills, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Milne, S.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Mimuro, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Min, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Mina, I.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Minor, A.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Mirhashemi, S.* . . . . . . . . . . . . . . . . . . . . . . . . . .30Mishima, Y. . . . . . . . . . . . . . . . . . . . . . . . .209, 253Mishin, Y. . . . . . . . . . . . . . . . . . . . .12, 76, 106, 238Mishra, B.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .196Mishra, P.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .160Mishra, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Mishra, R.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .112

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 283

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania284

Author Index

Mishra, R.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .200Mishra, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .273Misirlioglu, B. . . . . . . . . . . . . . . . . . . . . . . . . . . .72Misra, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .103, 111Misra, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .73, 91Misra, A.N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Misra, D.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .154Misture, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45Misture, S.T. . . . . . . . . . . . . . . . . . . . . . .10, 65, 149Misture, S.T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .159Mita, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Mitic, V.V.* . . . . . . . . . . . . . . . . . . . . . . . . . . .3, 138Mitsuishi, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Mitterer, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Mitwally, M.E.* . . . . . . . . . . . . . . . . . . . . . . . . .123Miyabayashi, H. . . . . . . . . . . . . . . . . . . . . . . . . . .97Miyamoto, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .134Miyamoto, N. . . . . . . . . . . . . . . . . . . . . . . . . . . .174Miyanishi, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .121Miyazaki, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .150Miyoshi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .8, 72Mizoguchi, T. . . . . . . . . . . . . . . . . . . . . . . . .69, 246Mizuno, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121Mizuno, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Mizuno, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92Mobasher, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Mobley, T.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Moelans, N.* . . . . . . . . . . . . . . . . . . . . . . . .16, 240Moeller, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .214Mohamed, A.E.* . . . . . . . . . . . . . . . . . . . . . . . . . .8Mohamed, W.M.* . . . . . . . . . . . . . . . . . . . . . . .103Mohammadi, F. . . . . . . . . . . . . . . . . . . . . . . . . .101Mohan Iyengar, R.* . . . . . . . . . . . . . . . . . . . . . . .48Mohanty, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .151Mohd Yusof, H.* . . . . . . . . . . . . . . . . . . . . . . . .246Mohrbacher, H.* . . . . . . . . . . . . . . . . . . . . . . . . .48Moldovan, P. . . . . . . . . . . . . . . . . . . . . . . . . .20, 21Mondal, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .135Monroe, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Monsegue, N. . . . . . . . . . . . . . . . . . . . . . . . . . . .200Monsegue, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . .29Montgomery, C.B. . . . . . . . . . . . . . . . . . . . . . . .203Montoya, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Montufar Jiménez, E.B. . . . . . . . . . . . . . . . . . . . .23Moody, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Moore, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211Moore, G.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Morales, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Morales, A.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Morales, L.A. . . . . . . . . . . . . . . . . . . . . . . . . . . .205Moran, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Moreaud, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .269Morelli, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Moreno, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Morgan, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Moriconi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Morimoto, T. . . . . . . . . . . . . . . . . . . . . . . . . . . .168Morioka, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Morita, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .61, 62Morley, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Morozovska, A.N. . . . . . . . . . . . . . . . . . . . .59, 185Morral, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Morral, J.E. . . . . . . . . . . . . . . . . . . . . . . . . .115, 151Morris, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .181Morris, D.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101Morris, J.W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Morris, P. . . . . . . . . . . . . . . . . . . . . . . . . . .230, 262Morris, P.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .261Morris, P.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .139Morrison, A.Q. . . . . . . . . . . . . . . . . . . . . . . . . .270Morss Clyne, A. . . . . . . . . . . . . . . . . . . . . . . . . .155

Mosavi khoei, M. . . . . . . . . . . . . . . . . . . . . . . . .253Moscoso, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .254Moseson, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Moseson, A.J.* . . . . . . . . . . . . . . . . . . . . . . .73, 173Mosher, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .147Moulton, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .135Mourton, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Mousavaizadeh, M. . . . . . . . . . . . . . . . . . . . . . . .31Mousavizade, M. . . . . . . . . . . . . . . . . . . . . . . . . .31Mu, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Muangnapoh, K. . . . . . . . . . . . . . . . . . . . . . . . .146Mughrabi, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . .92Muhlstein, C. . . . . . . . . . . . . . . . . . . . . . . . .73, 179Muhlstein, C.L. . . . . . . . . . . . . . . . . . . . . . .74, 181Mukherjee, A.K. . . . . . . . . . . . . . . . . . . . . . . . . . .53Mukherjee, A.K.* . . . . . . . . . . . . . . . . . . . . .52, 219Mukherjee, P.P.* . . . . . . . . . . . . . . . . . . . . . . . . .235Mukhopadhyay, A.* . . . . . . . . . . . . . . . . . . . . . .124Mukhopadhyay, S. . . . . . . . . . . . . . . . . . . . . . . .153Mukhopadhyay, S.M. . . . . . . . . . . . . .23, 196, 256Mukhopadhyaya, G. . . . . . . . . . . . . . . . . . . . . . .23Muller, I.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Muller, I.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Mullins, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . . .264Mumcu, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138Mumm, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250Mumm, D.R. . . . . . . . . . . . . . . . . . . . .66, 127, 248Mummery, P. . . . . . . . . . . . . . . . . . . . . . . . .16, 211Mun, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Munch, E. . . . . . . . . . . . . . . . . . . . . . . . . . .209, 222Munir, Z.A. . . . . . . . . . . . . . . . . . . . . . . . . .219, 257Munish, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125Munns, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Munroe, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Munroe, N.D. . . . . . . . . . . . . . . . . . . . . . . . . . . .131Muntean, G.G. . . . . . . . . . . . . . . . . . . . . . . . . . .208Murai, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Murakami, M. . . . . . . . . . . . . . . . . . . . . . . . . . .165Muralidhar, P. . . . . . . . . . . . . . . . . . . . . . . . . . .214Muralidharan, G. . . . . . . . . . . . . . . . . . . . . . . . .266Murari, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . .5, 166Murari, N.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Murayama, N. . . . . . . . . . . . . . . . . . . . . . . . . . .265Murayama, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .19Murch, G.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Murr, L.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Murray, C.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Murthylal, S. . . . . . . . . . . . . . . . . . . . . . . . . .33, 261Murty, K.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Mussi, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106Muta, H. . . . . . . . . . . . . . . . . . . . . . . . .10, 144, 206Muta, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Myers, J.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Myrjam, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74

N

Nag, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19, 122Nag, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248Nagaoka, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .207Nagata, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Nagel, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .178Nagira, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Nagpure, I.M.* . . . . . . . . . . . . . . . . . . . . . . . . . .215Nagy, P.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .244Nahm, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Nai, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .130, 229Nair, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Nair, K.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Nair, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153Naito, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .29, 87

Nakada, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Nakagawa, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .134Nakagawa, T. . . . . . . . . . . . . . . . . . . . . . . . . . . .243Nakahara, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Nakai, M. . . . . . . . . . . . . . . . . . . . . . . . . . .123, 154Nakajima, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Nakajima, T. . . . . . . . . . . . . . . . . . . . . . . . . . . .4, 39Nakamura, M. . . . . . . . . . . . . . . . . . . . . . . . . . .127Nakamura, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Nakamura, T.* . . . . . . . . . . . . . . . . . . . . . . . . . .109Nakamura, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . .109Nakano, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .225Nakashima, H. . . . . . . . . . . . . . . . . . . . . . . . . . .179Nakashima, T.* . . . . . . . . . . . . . . . . . . . . . . . . . .89Nakata, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208Nakayama, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Nakayama, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .53Nam, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Nam, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Nam, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Nambu, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .90, 112Nambu, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91Napolitano, R.E. . . . . . . . . . . . . . . . . . . . . . . . .157Napolitano, R.E.* . . . . . . . . . . . . . . . . . . . . . . . .216Napolskii, K.S.* . . . . . . . . . . . . . . . . . . . . . . . . . .30Narang, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Narayan, R.J.* . . . . . . . . . . . . . . . . . . . . . . . .82, 182Narayanan, B.* . . . . . . . . . . . . . . . . . . . . . . . . . .269Narayanan, M. . . . . . . . . . . . . . . . . . . . . . . . . . .100Narita, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Nash, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Nasrazadani, S.* . . . . . . . . . . . . . . . . . . . . . .43, 148Natarajan, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .273Nath, R. . . . . . . . . . . . . . . . . . . . . . . .165, 186, 230Nathal, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Nathan, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Natishan, P.M. . . . . . . . . . . . . . . . . . . . . . . . . . . .47Naugle, D.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Nauman, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Nawaz, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Nayak, B.B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .196Nayak, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Nelson, A.T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .227Nelson, T. . . . . . . . . . . . . . . . . . . . . . . . . . .118, 133Nemecek, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Nemes, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Nettleship, I. . . . . . . . . . . . . . . . . . . . . . . . .130, 256Nettleship, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . .130Neugebauer, J. . . . . . . . . . . . . . . . . . . . . . . . . . .147Neugebauer, J.* . . . . . . . . . . . . . . . . . . . . . . . . .216Newbauer, T.M. . . . . . . . . . . . . . . . . . . . . . . . . . .47Newell, J.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Ng, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250Ng, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Ngo, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Nguyen, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Nguyen, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .272Nguyen, Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Nguyen, T.Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Ni, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Ni, J.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Ni, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44, 139Niazi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Nichols, E.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .65Nicolas, N. . . . . . . . . . . . . . . . . . . . . . . . . .187, 243Nie, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Nie, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Nie, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .234Nielsen, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Niffenegger, M. . . . . . . . . . . . . . . . . . . . . . . . . .148Niihara, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 284

www.matscitech.org 285

Author Index

Niihara, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Niinomi, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Niinomi, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .154Nikbin, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Nikhil, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Nikitina, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Nili Ahmadabadi, M. . . . . . . . . . . . . . . . . . . . . . .21Nino, J.C.* . . . . . . . . . . . . . . . . . . . . . . . . .110, 152Nishida, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Nishikawa, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . .62Nishimizu, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .232Nishioka, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Niu, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Njoes, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Nobile, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194Noda, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139Noh, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Noma, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Noman, M. . . . . . . . . . . . . . . . . . . . . . . . . .167, 205Noor, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Norby, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Norfleet, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Norton, M.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .65Nothwang, W.D.* . . . . . . . . . . . . . . . . . . . . . . . .197Novick-Cohen, A.* . . . . . . . . . . . . . . . . . . .12, 182Nowell, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248Nuhfer, T.N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Numakura, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .58Nunez, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Nutt, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Nuzhnyy, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Nuzzo, R.G. . . . . . . . . . . . . . . . . . . . . . . . .183, 218Nychka, J.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .221Nygaard, F.B. . . . . . . . . . . . . . . . . . . . . . . . . . . .171

O

O’Keefe, M. . . . . . . . . . . . . . . . . . . . .165, 192, 256O’Keefe, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . . .245O’Keefe, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192O’Shaughnessy, J. . . . . . . . . . . . . . . . . . . . . . . . .236Obbard, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .186Oberacker, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .224Ocampo, J.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Ochi, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Ochi, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Odette, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Ogale, M.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Ogasawara, T. . . . . . . . . . . . . . . . . . . . . . . . . . . .154Ogata, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Ogawa, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Ogawa, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Ogden, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254Ogubuzo, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82Oguma, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Oguma, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Ogunmola, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Ogura, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Ogut, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Oh, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22, 80Oh, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226Oh, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Oh, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4, 17, 20OHara, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Ohashi, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Ohgaki, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Ohji, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .237Ohnishi, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94Ohta, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Ohta, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Ohyanagi, M. . . . . . . . . . . . . . . . . . . . . . . .100, 219

Oja, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Okabayashi, T. . . . . . . . . . . . . . . . . . . . . . . . . . .105Okamoto, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Okamoto, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .127Okano, M. . . . . . . . . . . . . . . . . . . . . . . . . . .28, 271Okatsu, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Okoshi, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Oladoye, A.M. . . . . . . . . . . . . . . . . . . . . . . . . . .136Olaya, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Olaya-Luengas, L.* . . . . . . . . . . . . . . . . . . .32, 136Olevsky, E.* . . . . . . . . . . . . . . . . . . . . . . . . .52, 219Oliver, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212Olson, D.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Olson, G.B. . . . . . . . . . . . . . . . . . . . . . . . . . . .14, 15Olson, G.B.* . . . . . . . . . . . . . . . . . . . . . . . . .45, 176Olson, L.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Omar, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110Onishi, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154Ono, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Oribe, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Orlita, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Orloff, N.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Orlovskaya, N. . . . . . . . . . . . . . . . . . . .10, 102, 117Orozco Hernández, H. . . . . . . . . . . . . . . . . . . .272Orozco-Hernández, H. . . . . . . . . . . . . . . . . . . . .25Ortega -Saenz, J. . . . . . . . . . . . . . . . . . . . . . . . .222Ortiz, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Osaka, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .206Osborne, E.W. . . . . . . . . . . . . . . . . . . . . . . . . . . .65Oseguera, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Osman, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Osoba, L.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Osterberg, D.D. . . . . . . . . . . . . . . . . . . . . .158, 206Otani, M. . . . . . . . . . . . . . . . . . . . . . .105, 146, 203Ott, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Ott, R.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Otto, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248Otugen, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .260Ouabadi, N. . . . . . . . . . . . . . . . . . . . . . . . . .85, 181Ovalle, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Ovsianikov, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .82Oyama, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Oyama, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8, 72Ozaki, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Ozolins, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107Ozolins, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .106

P

Padron, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Padture, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Padture, N.P. . . . . . . . . . . . . . . . . . . . . . . .196, 259Padture, N.P.* . . . . . . . . . . . . . . . . . . . . . . . . . .258Paik, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Painter, G.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Paital, S.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90Paital, S.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255Pal, T.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Palai, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Palaniyandi, V.* . . . . . . . . . . . . . . . . . . . . . . . . .147Palchesko, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .270Palmer, R.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Palumbo, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Pan, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Pan, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37, 141Pan, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202Pan, X. . . . . . . . . . . . . . . . . . . . . . . . . .76, 151, 262Pan, X.* . . . . . . . . . . . . . . . . . .60, 96, 106, 115, 233Pande, S.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Pandey, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .273Pandit, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139

Panguntani, S.* . . . . . . . . . . . . . . . . . . . . . . . . .199Pantano, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Pantelides, S.T. . . . . . . . . . . . . . . . . . . . . . . . . . .105Pappacena, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .58Paquette, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Paranthaman, M.P.* . . . . . . . . . . . . . . . . . . . . .264Paras, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Paraskevopoulos, N. . . . . . . . . . . . . . . . . .182, 268Paredes, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Pareige, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Parga, C.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Parish, C.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .257Parish, C.M.* . . . . . . . . . . . . . . . . . . . . . . . .64, 248Park, B.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Park, C. . . . . . . . . . . . . . . . . . . . . . . .16, 81, 96, 270Park, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139Park, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257Park, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16, 264Park, J.* . . . . . . . . . . . . . . . . . . . . . . .7, 81, 172, 203Park, J.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Park, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154Park, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Park, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Park, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Park, S. . . . . . . . . . . . . . . . . . . .22, 28, 36, 209, 221Park, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Park, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Parkin, I.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Parrington, R.J.* . . . . . . . . . . . . . . . . . . . . . . . .108Pascucci, M.R.* . . . . . . . . . . . . . . . . . . . . . . . . .138Patel, C.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Patel, G.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .148Patel, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93Patete, A.R. . . . . . . . . . . . . . . . . . . . . . . . . .135, 271Pathak, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Patil, L.A. . . . . . . . . . . . . . . . . . . . . . . . . . .165, 205Patrusheva, T.N.* . . . . . . . . . . . . . . . . . . . . . . . . .95Patwardhan, D. . . . . . . . . . . . . . . . . . . . . . . . . . .45Paul, S.N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Pauli, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Paulikas, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Paunovic, V. . . . . . . . . . . . . . . . . . . . . . . . . . .3, 138Pavlacka, R.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .85Pavlovic, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3Pavlovic, V.B. . . . . . . . . . . . . . . . . . . . . . . . . . . .138Pawlik, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Payawan, L.M. . . . . . . . . . . . . . . . . . . . . . . . . .4, 11Payer, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Payling, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Payne, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Payne, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Payne, D.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93Payraudeau, N. . . . . . . . . . . . . . . . . . . . . . . . . . .270Peacock, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Peaslee, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Pecard, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Pech-Canul, M.I.* . . . . . . . . . . . . . . . . . . . .30, 161Pecqueux, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . .270Pederson, L.R. . . . . . . . . . . . . . . . . . . . . . . . . . .198Pee, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .18, 27, 29Peeler, D.K. . . . . . . . . . . . . . . . . . . . . .143, 169, 170Pegg, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Pegg, I.L. . . . . . . . . . . . . . . . . . . . . . . .143, 226, 259Pekor, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Peña, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Peng, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Pennycook, S.* . . . . . . . . . . . . . . . . . . . . . . . . . .105Pennycook, S.J. . . . . . . . . . . . . . . . . . . . . . . . . . . .69Pense, A.W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .211Pereira, S.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Perez, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 285

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania286

Author Index

Peréz, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Perez, R. . . . . . . . . . . . . . . . . . . . . . . . . . .4, 17, 263Perez, T.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Pérez-Acosta, J.A.* . . . . . . . . . . . . . . . . . . . . . . . . .6Perkins, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Perni, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Perry, N.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Perry, N.H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Persson, K.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .69Peshwe, D.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Petford-Long, A.* . . . . . . . . . . . . . . . . . . . . . . .185Petford-Long, A.K. . . . . . . . . . . . . . . . . . . . . . .218Petit, E.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Petkovic, P. . . . . . . . . . . . . . . . . . . . . . . . . . . .3, 138Petkus, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Petrov, P.I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227Petrov, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Petrovic, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Petrovsky, V. . . . . . . . . . . . . . . . . . . . . . . . . . .9, 141Pettit, F.S. . . . . . . . . . . . . . . . . . . . . . . .15, 127, 144Petukhov, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Pfeiffenberger, N.T.* . . . . . . . . . . . . . . . . . . . . .259Phadke, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Phair, J.W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235Phatak, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218Phillpot, S.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Picard, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Piccirillo, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .191Pichler, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188Pickrell, G. . . . . . . . . . . . . . . . . . . . . .226, 258, 259Piehler, H.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .70Pierce, E.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .100Pierce, Z.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254Pietrzyk, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .113Pietzka, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Pilchak, A.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . .177Pileggi, R.G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Piña Barba, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .23Piña Barba, M.C. . . . . . . . . . . . . . . . . . . . . . . . . .23Piña-Barba, C.M.* . . . . . . . . . . . . . . . . . . . . . . . .23Pinasco, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Pinc, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Pinckney, L.R. . . . . . . . . . . . . . . . . . . . . . . . . . .125Pioszak, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .237Plaza, F.C. . . . . . . . . . . . . . . . . . . . . . . . . . . .16, 211Plaza, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Pletcher, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Podpirka, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Podpirka, A.A.* . . . . . . . . . . . . . . . . . . . . . . . . .164Podual, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Poeppelmeier, K.R. . . . . . . . . . . . . . . . . . .149, 217Polastre, R.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Polat, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Polcawich, R.G. . . . . . . . . . . . . . . . . . . . . . . . . . .36Polkanov, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .142Pollard, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .217Pollock, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Pollock, T.M. . . . . . . . . . . . . . . . . . . .157, 178, 212Polomoff, N. . . . . . . . . . . . . . . . . . . . .165, 186, 230Polotai, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Ponack, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Ponge, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Poole, W.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Popescu Pogrion, N.* . . . . . . . . . . . . . . . . . . . . .75Popescu, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Popescu, G.* . . . . . . . . . . . . . . . . . . . . . . . . . .20, 21Popovici, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . .264Popovics, J.S. . . . . . . . . . . . . . . . . . . . . . . . . . . .123Popp, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Porfiri, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55Porter, J.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248

Porter, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Poston, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Poterala, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Pouranvari, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .31Powell, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Powell, A.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .267Powell, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164Prabhakaran, R. . . . . . . . . . . . . . . . . . . . . . . . . .104Pradhan, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Pradhan, D.K. . . . . . . . . . . . . . . . . . . . . . . . . . . .5, 9Pradhan, D.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Pradhan, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Pradhan, S.K. . . . . . . . . . . . . . . . . . . . . . . . . . . .196Prakash, K.H. . . . . . . . . . . . . . . . . . . . . . . . . . . .159Prakash, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193Prakash, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156Pramanick, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .94Pramanick, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Prasad, S.V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Prasannavenkatesan, R. . . . . . . . . . . . . . . . . . . .241Prasatkhetragarn, A. . . . . . . . . . . . . . . . . . . . . .142Pratten, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Preckwinkel, U. . . . . . . . . . . . . . . . . . . . . . . . . . .76Prichard, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Principe, C.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Principe, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Priya, S. . . . . . . . . . . . . .7, 29, 59, 96, 139, 140, 204Proa-Flores, P.M.* . . . . . . . . . . . . . . . . . . . . . . .250Proffen, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Proffit, D.* . . . . . . . . . . . . . . . . . . . . . . . . .146, 213Provis, J.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52Provis, J.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125Pryds, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Prytz, Ø.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Przybyla, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Przybyla, C.P.* . . . . . . . . . . . . . . . . . . . . . . . . . .242Ptashkin, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Pujari, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Pulskamp, J.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Puri, S.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23Purja Pun, G.P.* . . . . . . . . . . . . . . . . . . . . . . . . . .76Pushko, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Puskar, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Pusztai, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Puszynski, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Putatunda, S.K.* . . . . . . . . . . . . . . . . . . . . . . . .152Puttaiah, C.M. . . . . . . . . . . . . . . . . . . . . . . . . . .229Pye, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34Pyshkin, S.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . .182

Q

Qadri, S.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Qian, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .245Qian, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Qian, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Qian, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Qian, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Qiao, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .212Qiao, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Qidwai, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .210Qingchao, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Qiu, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Qu, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113, 145Qu, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Qu, P.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Qu, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Quast, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179Querin, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133Querin, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133Quickel, G.T. . . . . . . . . . . . . . . . . . . . . . . . . . . .147

Quickel, G.T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .42Quinones, S.A. . . . . . . . . . . . . . . . . . . . . . . . . . .122Quintana, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .269

R

R.k, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Raabe, D. . . . . . . . . . . . . . . . . . . . .74, 80, 147, 151Radhakrishnan, P. . . . . . . . . . . . . . . . . . . . . . . .236Radmilovic, V. . . . . . . . . . . . . . . . . . . . . . . . . . .239Radovic, M. . . . . . . . . . . . . . . . . . . . . .10, 102, 181Radziszewski, P. . . . . . . . . . . . . . . . . . . . . . . . . .241Raghavan, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .186Rago, P.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Rahaman, M.N. . . . . . . . . . . . . . . . . . . . . . . .23, 82Rahman, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .224Rahman, S.W.* . . . . . . . . . . . . . . . . . . . . . . . . . . .19Rai, R.N.* . . . . . . . . . . . . . . . . . . . . . . . . . .215, 216Raitano, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Raj, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Raj, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Rajagopalan, S. . . . . . . . . . . . . . . . . . . . . . .122, 248Rajagopalan, S.* . . . . . . . . . . . . . . . . . . . . . .19, 248Rajgarhia, R.K.* . . . . . . . . . . . . . . . . . . . . . .16, 212Raki, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .155Raki, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124Rakowski, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .234Rama Reddy, S.K.* . . . . . . . . . . . . . . . . . . . . . . .229Ramakrishna, S.* . . . . . . . . . . . . . . . . . . . . . . . . .81Ramalingam, S.* . . . . . . . . . . . . . . . . . . . . . . . .161Ramam, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Ramanathan, S. . . . . . . . . . . . . . . . . . . . . . .96, 164Ramanathan, S.* . . . . . . . . . . . . . . . . . . . . . . . . .51Ramesh, R. . . . . . . . . . . . . . . . . . . . . . . . . .165, 262Ramirez, J.C. . . . . . . . . . . . . . . . . . . . . . . . . . . .205Ramírez-Vargas, E. . . . . . . . . . . . . . . . . . . . . . . .11Ramirez-Vargas, E. . . . . . . . . . . . . . . . . . . . . . .261Randall, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .149Randall, C.* . . . . . . . . . . . . . . . . . . . . . . . .138, 243Randall, C.A. . . . . . . . . . . . . . . . . . . . .17, 140, 213Rao, K.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .267Rao, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59, 186Raphael, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Raphael, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Raszewski, F.C.* . . . . . . . . . . . . . . . . . . . . .169, 170Rauch, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Rauscher, M.D. . . . . . . . . . . . . . . . . . . . . . . . . . .12Raveau, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233Ravi Dastane, R. . . . . . . . . . . . . . . . . . . . . . . . . .207Ravi, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Ravi, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Ravindra, N.M. . . . . . . . . .182, 215, 216, 246, 268RaviRaj, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Ray, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238Ray, K.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31, 80Ray, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90Reade, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103Reaney, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39Reaney, I.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . .185Reck, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Reddy, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .206Reddy, R.G. . . . . . . . . . . . . . . . . . . . . . . . .103, 228Reddy, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167Reed, B.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .217Regier, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Reichart, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Reichlin, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .148Reilly, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235Reimanis, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Reimanis, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Reimanis, I.E. . . . . . . . . . . . . . . . . . . . . . . .125, 172

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 286

www.matscitech.org 287

Author Index

Reiterer, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Reiterer, M.W.* . . . . . . . . . . . . . . . . . . . . . . . . .239Ren, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40, 209Ren, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .175, 270Ren, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Ren, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Ren, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .244, 245Rendon-Angeles, J.C. . . . . . . . . . . . . . . . . . .19, 25Renk, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Reuter, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42Reynolds, M.M.* . . . . . . . . . . . . . . . . . . . . . . . . .65Reynolds, W. . . . . . . . . . . . . . . . . . . . . . . . . . . .172Rezaeian, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .255Rice, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Richards, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .193Richards, V.L. . . . . . . . . . . . . . . . . . . . . . . . . . . .270Rickman, J.M. . . . . . . . . . . . . . . . . . . . . . . . . . . .76Rider, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Ridgway, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Rieken, J.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .226Rieske-Kinney, L.K. . . . . . . . . . . . . . . . . . . . . . .215Rigaud, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Riley, D.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52Ringnalda, J. . . . . . . . . . . . . . . . . . . . . . . . . . .41, 64Rioja, R.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54Rivas-Vázquez, L.* . . . . . . . . . . . . . . . . . .5, 11, 261Rivas-Vázquez, L.P. . . . . . . . . . . . . . . . . . . . .19, 24Rivas-Vazquez, L.P. . . . . . . . . . . . . . . . . . . . . . . .25Rivera, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3, 205Rivero, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Rivero, R.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Rivolta, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Robert, R. . . . . . . . . . . . . . . . . . . . . . . . . . .145, 146Robertson, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Robertson, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Robinson, D.S. . . . . . . . . . . . . . . . . . . . . . . . . . . .99Robinson, P.W.* . . . . . . . . . . . . . . . . . . . . . . . . . .35Rocha-Rangel, E. . . . . . . . . . . . . . . . . . . . . . . .5, 11Rödel, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Rodela, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Rodiers, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Rodríguez Santoyo, H.H. . . . . . . . . . . . . . . . . . .23Rodríguez Santoyo, H.H.* . . . . . . . . . . . . . . . . .23Rodriguez, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Rodriguez, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .59Rodriguez-Ibabe, J.M. . . . . . . . . . . . . . . . . . . . .118Roeder, R.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .221Rohatgi, P.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Rohatgi, P.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .163Rohn, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .159Rohrer, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238Rohrer, G.* . . . . . . . . . . . . . . . . . . . . .105, 167, 210Rohrer, G.S. . . . . . . . . . . . . . . . . . . . . . . . . .68, 223Rojas, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200Rojas-George, G. . . . . . . . . . . . . . . . . . . . . . . . .226Rollett, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Rollett, A.D. . . . . . . . . . . . . . . . . . . . . .45, 148, 267Rollins, B.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42Rollins, B.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .147Romanes, M.C. . . . . . . . . . . . . . . . . . . . . . . . . .249Romasco, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Romero-Romo, M.A. . . . . . . . . . . . . . . . . . . .5, 11Rong, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79Rong, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Rong, Y.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236Ronning, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233Rook, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Roosen, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .54, 60Rosenberger, A.H. . . . . . . . . . . . . . . . . . . . . . . .177Roslyakov, I.V. . . . . . . . . . . . . . . . . . . . . . . . . . . .30Rossa, A. . . . . . . . . . . . . . . . . . . . . . . . . . .4, 17, 263

Rossa, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Rosseinsky, M.J. . . . . . . . . . . . . . . . . . . . . . . . . . .46Rossetti, G.A.* . . . . . . . . . . . . . . . . . . . . . . . .59, 94Rotan, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Roters, F. . . . . . . . . . . . . . . . . . . . . . . . . . . .147, 151Roth, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Roth, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Rouleau, C.M. . . . . . . . . . . . . . . . . . . . . . . . . . . .63Roy, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Roy, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Roy, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Roy, M.* . . . . . . . . . . . . . . . . . . . . . . .129, 270, 272Roy, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3, 101Ruan, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Rubal, M.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .133Rubisoff, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .133Rubisoff, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . .133Rudnev, V.* . . . . . . . . . . . . . . . . . . . . . . . . .188, 252Ruehle, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Ruggles-Wrenn, M.* . . . . . . . . . . . . . . . . . . . . .197Ruglovsky, J.L. . . . . . . . . . . . . . . . . . . . . . . . . . . .95Rührup, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .149Rulis, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265Rulis, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Rupich, M.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .93Russell, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .272Ryan, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Ryu, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .7, 245, 253

S

Saal, J.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Saavedra-Arias, J. . . . . . . . . . . . . . . . . . . . . . . . . .40Saavedra-Arias, J.J. . . . . . . . . . . . . . . . . . . . . . . .5, 7Saavedra-Arias, J.J.* . . . . . . . . . . . . . . . . . . . . . . . .9Sabau, A.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113Sabau, A.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Sabih, A.* . . . . . . . . . . . . . . . . . . . . . . . . . .240, 241Sachanandani, R. . . . . . . . . . . . . . . . . . . . . . . . . .85Sadangi, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Sadek, A.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28Saengdeejing, A.* . . . . . . . . . . . . . . . . . . . . . . . .246Saghizadeh, H.* . . . . . . . . . . . . . . . . . . . . . . . . .242Saha, R.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Sahu, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Saigal, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142Saito, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Saito, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Saito, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218Saiz, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .209, 222Saiz, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Sakaguchi, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Sakaguchi, Y. . . . . . . . . . . . . . . . . . . . . . . . .78, 241Sakai, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Sakai, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Sakata, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Sakka, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Sakulich, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Sakuma, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Salageheh, N. . . . . . . . . . . . . . . . . . . . . . . . . . . .241Salary, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Salas, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .155Salas, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Saldana, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254Salem, H.G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .28Salem, J.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Sall, A.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .237Salvador, J.R. . . . . . . . . . . . . . . . . . . . . . . . . . . .174Salvador, P. . . . . . . . . . . . .62, 63, 65, 167, 205, 238Salvador, P.* . . . . . . . . . . . . . . . . . . . . . . . . .72, 166Salvador, P.A. . . . . . . . . . . . . . . . . . . . . . . .140, 167

Samant, A.N.* . . . . . . . . . . . . . . . . . . . .26, 86, 113Samelyuk, A.V. . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Sammes, N.M.* . . . . . . . . . . . . . . . . . . . . . . . . .102Samuel, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188Sanchez Cervantes, E.M. . . . . . . . . . . . . . . . . . .258Sanchez, S.I. . . . . . . . . . . . . . . . . . . . . . . . .183, 218Sanders, T.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Sanders, T.H.* . . . . . . . . . . . . . . . . . . . . . . . . . .119Sangghaleh, A.* . . . . . . . . . . . . . . . . . . . . . . . . .226Sanjurjo, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Sankar, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Sano, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Sano, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Sano, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85, 89Sano, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109Santala, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Santella, M.L. . . . . . . . . . . . . . . . . . . . . . . . . . . .133Santhanam, M. . . . . . . . . . . . . . . . . . . . . . . . . .125Sarappa, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200Sarkar, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65Sarkar, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189Sarma, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Sarmago, R.V. . . . . . . . . . . . . . . . . . . . . . . . . . .4, 11Sarrafi, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .260Sarrafi, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .260Sase, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110Sastry, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Satet, R.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .176Sato, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29, 207Sato, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Sato, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Sato, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Satpathy, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139Saucedo-Muñoz, M.L. . . . . . . . . . . . . . . . . . . . . .75Sauvage, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .149Savic, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Saxena, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .16, 212Saxey, D.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Sayir, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .171, 231Sayir, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .171Saylor, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Saylor, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . .45, 254Scattergood, R.O. . . . . . . . . . . . . . . . . . . . . . . . .152Schadler, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Schaffnit, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247Scharf, T.W. . . . . . . . . . . . . . . . . . . . . . . . .122, 130Scharf, T.W.* . . . . . . . . . . . . . . . . . . . . . . .249, 271Schenck, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203Schenck, P.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .95Scherer, G.W.* . . . . . . . . . . . . . . . . . . . . . . . . . .156Scheu, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Schich, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Schiffer, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Schintlmeister, A. . . . . . . . . . . . . . . . . . . . . . . . .179Schirer, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .215Schlepuetz, C. . . . . . . . . . . . . . . . . . . . . . . . . . .185Schlesinger, M.E. . . . . . . . . . . . . . . . . . . . . . . . . .19Schlom, D. . . . . . . . . . . . . . . . . . . . . . . . . . .62, 262Schlom, D.G. . . . . . . . . . . . . . . . . . . . . . . . .95, 117Schmetterer, C. . . . . . . . . . . . . . . . . . . . . . . . . . .99Schmidt, Jr. - P.E., F.E.* . . . . . . . . . . . . . . . . . . .211Schmidt, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Schneibel, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19Schneider, C.W. . . . . . . . . . . . . . . . . . . . . . . . . .166Schneider, G. . . . . . . . . . . . . . . . . . . . . . . . . . . .178Schneider, J. . . . . . . . . . . . . . . . . . . . . . . . .133, 184Schneider, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .261Schoenung, J.M. . . . . . . . . . . . . . .53, 135, 136, 158Schofield, J.M.* . . . . . . . . . . . . . . . . . . . . . . . . .170Schreiber, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Schreiber, H.D.* . . . . . . . . . . . . . . . . . . . . . . . . . .64

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 287

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania288

Author Index

Schubert, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . .179Schubert, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Schuh, C.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Schuller, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Schultz, B.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .163Schultz, B.F.* . . . . . . . . . . . . . . . . . . . . . . . . . . .163Schulz, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196Schurwanz, M.* . . . . . . . . . . . . . . . . . . . . . . . . .141Schuster, B.E. . . . . . . . . . . . . . . . . . . . . . . . . . . .111Schwartz, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Schwartz, R.W.* . . . . . . . . . . . . . . . . . . . . . . .56, 94Schweitzer, J.S. . . . . . . . . . . . . . . . . . . . . . . . . . . .50Sciammarella, F. . . . . . . . . . . . . . . . . . . . . . . . . .199Sclosa, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Scotch, A.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Scott, B.L.* . . . . . . . . . . . . . . . . . . . . . . . . .226, 258Scott, J.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Scumpu, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Seager, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .236Seal, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53, 87Sears, J.W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .232Sebastian, M.T. . . . . . . . . . . . . . . . . . . . . . . . . . . .37Sechrist, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Seelam, U.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .192Seetharaman, S. . . . . . . . . . . . . . . . . . . . . .238, 251Segall, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Seguela, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214Segurado, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55Sehirlioglu, A. . . . . . . . . . . . . . . . . . . . . . . . . . .171Sehirlioglu, A.* . . . . . . . . . . . . . . . . . . . . . . .46, 231Sehitolgu, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .147Seidman, D.N. . . . . . . . . . . . . . . . . . . . . . . . . . .247Seidman, D.N.* . . . . . . . . . . . . . . . . . . . . . .45, 183Sekiguchi, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Sekino, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Selbach, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Self, B.G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Selig, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Selvamanickam, V. . . . . . . . . . . . . . . . . . . . . . . .264Semboshi, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Semones, J.E. . . . . . . . . . . . . . . . . . . . . . . . . . . .152Sen, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Senguttuvan, N. . . . . . . . . . . . . . . . . . . . . . . . . .141Seo, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Seok, C. . . . . . . . . . . . . . . . . . . . . . . . . . .33, 34, 244Seok, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Serbruyns, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .240Sereda, B.* . . . . . . . . . . . . . . . . . . . . . . .13, 75, 189Serincan, M.F. . . . . . . . . . . . . . . . . . . . . . . . . . .102Serquis, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Sertel, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138Setyawan, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .42Sevik, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Seyfarth, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Sfeir, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Sha, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Sha, Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Shafer, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Shah, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Shahhosseini, A.* . . . . . . . . . . . . . . . . . . . .252, 253Shahhosseini, M. . . . . . . . . . . . . . . . . . . . . . . . .252Shakouri, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .104Sham, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227Shamimi Nouri, A.* . . . . . . . . . . . . . . . . . . . . .156Shan, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Shang, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Shang, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Shang, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Shang, S. . . . . . . . . . . . . . . . . . .16, 19, 32, 217, 247Shang, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16Shankar, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .125

Shankar, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Shanker, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193Shanov, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196Shao, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227Sharapova, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Sharghi-Moshtaghin, R. . . . . . . . . . . . . . . . . . . .47Sharma, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Sharma, G.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Shaw, L.* . . . . . . . . . . . . . . . . . . . . . . .130, 222, 244Shechtman, D. . . . . . . . . . . . . . . . . . . . . . . . . . .226Sheikh, M.A. . . . . . . . . . . . . . . . . . . . . . . . .16, 211Shelton, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63Shen, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113Shen, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59, 95Shen, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .111, 196Sheng, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95Shepard, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .245Sherwood, W. . . . . . . . . . . . . . . . . . . . . . . . . . . .272Shet, S.* . . . . . . . . . . . . . . . . . . . . . . .182, 215, 246Sheyko, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Shi, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253Shi, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .213Shi, M.F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154Shi, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113Shi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Shi, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68Shi, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15, 174Shibata, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265Shibata, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Shifler, D.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Shikanai, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Shim, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88Shimamura, J.* . . . . . . . . . . . . . . . . . . . . . . . . .221Shimamura, K.* . . . . . . . . . . . . . . . . . . . . . . . . .141Shimamura, T. . . . . . . . . . . . . . . . . . . . . . . . . . .244Shimizu, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Shimizu, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .148Shin, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107Shin, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Shindoho, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .154Shingledecker, J.P. . . . . . . . . . . . . . . . . . . . . . . .217Shinozaki, D.M. . . . . . . . . . . . . . . . . . . . . . . . . .214Shiozaki, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Shiozawa, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Shiozawa, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .109Shipley, R.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70Shirai, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Shishkov, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Shivashankar, S.A. . . . . . . . . . . . . . . . . . . . . . . .129Shmygaleva, T. . . . . . . . . . . . . . . . . . . . . . . . . . . .25Shoda, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Shofner, M.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Shojan, P.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Shqau, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138Shrestha, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88Shubilla, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Shukla, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Shulman, H.S. . . . . . . . . . . . . . . . . . . . . . .128, 194Shulman, H.S.* . . . . . . . . . . . . . . . . . . . . . . . . .128Shyam, A.* . . . . . . . . . . . . . . . . . . . . . . . . .101, 212Si, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Sichel, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Siddle, D.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Sidorko, V.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Siebach, K.L. . . . . . . . . . . . . . . . . . . . . . . . . . . .128Siegel, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106Sigmund, W.M.* . . . . . . . . . . . . . . . . . . . . . . . .195Sikha, S.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Silva, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .4, 17, 263Silva, J.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Silva, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82

Sim, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Simacek, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55Simoes, D.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . .229Sin, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Sinclair, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Sinclair, D.C. . . . . . . . . . . . . . . . . . . . . . . . . .37, 61Sindelar, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233Singh Anterpreet, B.* . . . . . . . . . . . . . . . . . . . .204Singh, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130Singh, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Singh, A.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261Singh, A.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .224Singh, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Singh, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Singh, G. . . . . . . . . . . . . . . . . . . . . . . . . . . .183, 215Singh, G.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Singh, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .193Singh, M. . . . . . . . . . . . . . . . . . . . . . . . . . .182, 199Singh, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Singh, M.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Singh, M.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Singh, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Singh, N.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Singh, N.B.* . . . . . . . . . . . . . . . . . . . . . . . .128, 268Singh, O.P. . . . . . . . . . . . . . . . . . . . . . . . . .215, 268Singh, P. . . . . . . . . . . . . . . . . . . .145, 171, 234, 235Singh, R.N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .171Singh, R.N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Singh, R.P. . . . . . . . . . . . . . . . . . . . . .224, 261, 273Singh, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200Singh, S.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .171Singh, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Singh, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . .87, 191Singleton, O.R.* . . . . . . . . . . . . . . . . . . . . . . . . .266Sinha, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257Sinnott, S.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Sinnott, S.B.* . . . . . . . . . . . . . . . . . . . . . . . . . . .150Sintay, S.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .148Sisson, R.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .236Sisson, R.D.* . . . . . . . . . . . . . . . . . . . . . . . . .79, 236Sitar, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Skapin, S.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Skidmore, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39Skowronski, M. . . . . . . . . . . . . .140, 166, 167, 205Skurski, M.A. . . . . . . . . . . . . . . . . . . . . . . . . . . .168Smid, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . .160, 223Smith, B. . . . . . . . . . . . . . . . . . . . . . . . . . . .200, 256Smith, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Smith, G.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Smith, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220Smith, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Smith, J.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54Smith, M.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . .143Smith, S.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Snider, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Snow, C.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Snyder, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208Snyder, G.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Snyder, M.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .189So, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119So, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261Soboyejo, W.O.* . . . . . . . . . . . . . . . . . . . . . . . . . .49Sofie, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Sofie, S.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Sohma, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Sohn, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Sohn, Y. . . . . . . . . . . . . . . . . . . . . . .18, 76, 151, 184Sojka, P.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255Solberg, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Solomon, D.G. . . . . . . . . . . . . . . . . . . . . . . . . . . .21Solterbeck, C. . . . . . . . . . . . . . . . . . . . . . . . . . . .250

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 288

www.matscitech.org 289

Author Index

Sonderegger, B. . . . . . . . . . . . . . . . . . . . . . . . . .218Sonderegger, B.* . . . . . . . . . . . . . . . . . . . . . . . .115Song, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .244Song, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Song, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Song, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Soni, S.K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49Soranakom, C. . . . . . . . . . . . . . . . . . . . . . . . . . . .50Sorensen, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Sorge, J.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Soriano-Vargas, O. . . . . . . . . . . . . . . . . . . . . . . . .75Sosa-Rodríguez, R. . . . . . . . . . . . . . . . . . . . . . .272Soshnikov, R. . . . . . . . . . . . . . . . . . . . . . . . . . . .143Souders, K.E. . . . . . . . . . . . . . . . . . . . . . . . . . . .168Soukiassian, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .62Souza, D.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Souza, R.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Spanos, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Spaulding, N. . . . . . . . . . . . . . . . . . . . . . . . . . . .186Spearot, D.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .16Spearot, J.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Spears, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Specht, E.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Specht, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Speer, J.G. . . . . . . . . . . . . . . . . . . . . . . . . . . .79, 119Spitsberg, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Spowart, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113Spowart, J.E. . . . . . . . . . . . . . . . . . . . . . . . .104, 114Spowart, J.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .55Spreitzer, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Sprogis, E.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Sridharan, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .40Sridharan, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Srinivasan, K.R. . . . . . . . . . . . . . . . . . . . . . . . . .153Srinivasan, R. . . . . . . . . . . . . . . . . . . . . . . .117, 247Srinivasan, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .101Srivastava, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .88Srivastava, G.* . . . . . . . . . . . . . . . . . . . . . . . . . .142Srivastava, V.K.* . . . . . . . . . . . . . . . . . . . . . . . . .200Srolovitz, D.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .68Srot, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Ss, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Stackpoole, M. . . . . . . . . . . . . . . . . . . . . . . . . . .131Stafslien, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Stafslien, S.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .190Stainbrook, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . .59Stan, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233Stan, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Stankus, J.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Staub, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Stefanakos, E. . . . . . . . . . . . . . . . . . . . . . . . . . . .101Stefanik, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Stefanovsky, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Stefanovsky, S.* . . . . . . . . . . . . . . . . . . . . . . .8, 142Steigerwald, M. . . . . . . . . . . . . . . . . . . . . . . . . .256Steighner, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .181Steinbach, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . .247Steiner, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .177Stephens, J.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Stephenson, G. . . . . . . . . . . . . . . . . . . . . . . . . . . .77Stevenson, A.J. . . . . . . . . . . . . . . . . . . . . . . . . . . .86Stevenson, J. . . . . . . . . . . . . . . . .145, 171, 234, 235Stevenson, M.E. . . . . . . . . . . . . . . . . . . . . . . . . . .71Stewart, B.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Stewart, G.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Stoch, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Stoch, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Stoch, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8, 26Stock, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Stokes, D.J. . . . . . . . . . . . . . . . . . . . . . . . . . . .41, 64Storey, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70

Storey, R.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108Stoudt, M.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .113Strachan, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .147Strachan, D. . . . . . . . . . . . . . . . . . . . . . . . . .99, 169Strand, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Strandlund, H. . . . . . . . . . . . . . . . . . . . . . . . . . .114Stratton, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Strawbridge, R.R. . . . . . . . . . . . . . . . . . . . . . . . .254Streiffer, S.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Strong, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Struble, L.J. . . . . . . . . . . . . . . . . . . . . .123, 124, 155Struble, L.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Stuckenholz, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .60Sturgeon, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Stutzman, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83Stutzman, P.E. . . . . . . . . . . . . . . . . . . . . . . . . . . .83Su Gun, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Su, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3, 8, 13Su, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14Su, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17Suarez, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Suárez, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Suarez, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Suárez, O. . . . . . . . . . . . . . . . . . . . . . . . .21, 32, 136Suárez, O.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Suarez, O.M. . . . . . . . . . . . . . . . . . . . . . . . . . .20, 32Suárez-Orduña, R. . . . . . . . . . . . . . . . . . .5, 11, 261Suarez-Orduña, R.* . . . . . . . . . . . . . .19, 24, 25, 26Subhash, G.* . . . . . . . . . . . . . . . . . . . . . . .117, 156Subodh, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Subramanian, K. . . . . . . . . . . . . . . . . . . . . . . . .265Subramanian, K.* . . . . . . . . . . . . . . . . . . . .18, 115Subramanian, K.N. . . . . . . . . . . . . . . . . . . . . . . .38Suda, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172Suematsu, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Sugiura, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .246Suh, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79Suh, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221Suh, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Suhre, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Sui, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .195Sukhleen Bindra, N. . . . . . . . . . . . . . . . . . . . . .204Sumiya, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141Sumption, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .264Sun, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Sun, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106Sun, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3Sun, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Sun, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172Sun, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .197Sunayama, H.* . . . . . . . . . . . . . . . . . . . . . . . . . .220Sundaram, S.K.* . . . . . . . . . . . . . . . . . . . . .34, 208Sundlof, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .167Sundlof, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Sung, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Sunny, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156Sunseri, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115Surappa, M.K.* . . . . . . . . . . . . . . . . . . . . .163, 200Suryanarayana, C. . . . . . . . . . . . . . . . . . . . . . . .192Susan, D.F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Sussman, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Suvorov, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Suzuki, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Suzuki, K. . . . . . . . . . . . . . . . . . . . . . . . . . .168, 203Suzuki, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Suzuki, T. . . . . . . . . . . . . . . . . . . .53, 102, 170, 171Suzuki, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Suzuki, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . .78, 109Swink, A.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64Sychterz, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Syvertsen, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66

Szczepanski, C.J.* . . . . . . . . . . . . . . . . . . . . . . .108Szepesi, C.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .224

T

Tachibana, T.* . . . . . . . . . . . . . . . . . . . . . . . . . .134Tada, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Tadesse, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Taftø, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Taherabadi, L. . . . . . . . . . . . . . . . . . . . . . . . . . . .13Taheri, M.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . .217Tai, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Takagi, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Takahashi, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Takahashi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .218Takai, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Takane, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Takeda, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43Takeda, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Takeda, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Takemoto, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Takenaka, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Takeuchi, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Tamura, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Tan, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Tan, X. . . . . . . . . . . . . . . . . . . . . . . . .139, 202, 269Tanaka, K. . . . . . . . . . . . . . . . . . . . . . .168, 203, 206Tanaka, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Tanaka, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74Tanase, M. . . . . . . . . . . . . . . . . . . . . . . . . .185, 218Tancret, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .270Tancret, F.* . . . . . . . . . . . . . . . . . . . . . . . . . .16, 238Tandon, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Tanei, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Tang, G. . . . . . . . . . . . . . . . . . . . . . . . . . . .111, 204Tang, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Tang, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Tang, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Tang, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65Tang, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .69, 176Tang, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47, 78Tang, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17Tang, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Tang, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Tang, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15Tani, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257Taniguchi, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .263Tanzer, A.B.* . . . . . . . . . . . . . . . . . . . . . . . . . . .177Tao, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Tao, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137Tasaki, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Task, M.N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Tatami, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .29, 208Tatami, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .5, 225Tate, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254Tatsumi, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Tatsumi, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Teague, M. . . . . . . . . . . . . . . . . . . . . . . . . .132, 249Teague, M.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Tegze, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Tekkaya, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Templeton, J. . . . . . . . . . . . . . . . . . . .145, 234, 235Tenne, D.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95Tennent, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .137Terauchi, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Terzieff, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Thackeray, M.M. . . . . . . . . . . . . . . . . . . . . . . . .187Thadhani, N. . . . . . . . . . . . . . . . . . . . . . . . . . . .250Thadhani, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . .21Thayer, G.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Thiel, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 289

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania290

Author Index

Thiele, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Thiery, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Thillaiyan, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Thom, A.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Thomas, E. . . . . . . . . . . . . . . . . . . . . . . . . .146, 203Thomas, E.L.* . . . . . . . . . . . . . . . . . . . . . . . . . .105Thomas, J.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84Thomas, R. . . . . . . . . . . . . . . . . . . . .5, 7, 9, 40, 166Thomas, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5Thompson, A. . . . . . . . . . . . . . . . . . . . . . . . . . .147Thompson, C.* . . . . . . . . . . . . . . . . . . . . . . . . . .77Thompson, D. . . . . . . . . . . . . . . . . . . . . . . . . . .174Thompson, J.D. . . . . . . . . . . . . . . . . . . . . . . . . .233Thompson, M.J.* . . . . . . . . . . . . . . . . . . . . .30, 131Thornotn, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .112Thornton, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .131Thornton, K. . . . . . . . . . . . . . . . . . . . . . . . .76, 102Thornton, K.* . . . . . . . . . . . . . . . . . . . . . . . . . .210Thornton, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Tiely, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .247Tihay, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Tikekar, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Tiley, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .130, 248Tiley, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Timm, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Timm, E.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175Timur, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Tinberg, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39Tiruvalam, R.* . . . . . . . . . . . . . . . . . . . . . . . . . .249Tischler, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77Tiwari, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Toberer, E.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Tobita, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Toda, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .78, 241Todaka, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184Todd, J.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .255Todd, P.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Todd, R.I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53Togambayeva, A.* . . . . . . . . . . . . . . . . . . . . .12, 25Toggweiler, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .146Tokutsu, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Tomeckova, V. . . . . . . . . . . . . . . . . . . . . . .193, 194Tomeckova, V.* . . . . . . . . . . . . . . . . . . . . .193, 194Tomes, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Tomes, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Tomimatsu, T.* . . . . . . . . . . . . . . . . . . . . . . . . . .74Tominaga, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .243Tomozawa, M. . . . . . . . . . . . . . . . . . . . . . . . . . .127Tomozawa, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .84Tomsia, A.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Tomsia, A.P.* . . . . . . . . . . . . . . . . . . . . . . .209, 222Tonello, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Tong, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Topolov, V.Y.* . . . . . . . . . . . . . . . . . . . . . . . . . .6, 33Topping, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .256Topping, T.D. . . . . . . . . . . . . . . . . . . . . . . . . . . .135Topping, T.D.* . . . . . . . . . . . . . . . . . . . . . . . . . .136Torbet, C.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Torkamany, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .31Torkelson, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86Torrens, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Torres, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Torres, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Torres-Garibay, C. . . . . . . . . . . . . . . . . . . .193, 194Torres-Garibay, C.* . . . . . . . . . . . . . . . . . . . . . .194Torsner, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90Tortorelli, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Tosha, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .148Toth, G.I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Totokawa, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .257Touzin, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

Tran, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Trapaga, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Traversa, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .129Trejo, R.M. . . . . . . . . . . . . . . . . . . . . . . . . .175, 209Tretyakov, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27Tretyakov, Y.D. . . . . . . . . . . . . . . . . . . . .27, 30, 225Trice, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .127Trice, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Tripathi, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Tritt, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Tritt, T.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Trivedi, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115Trofimenko, A.V. . . . . . . . . . . . . . . . . . . . . . . . .143Trolier-McKinstry, S. . . . . . . . . . . .60, 95, 140, 204Trolier-McKinstry, S.* . . . . . . . . . . . . . . . . . .36, 39Tromas, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .181Trottier, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Trottmann, M. . . . . . . . . . . . . . . . . . . . . . . . . . .146Trujillo, C.P. . . . . . . . . . . . . . . . . . . . . . . . . .44, 220Trumble, K.P. . . . . . . . . . . . . . . . . . . . . . . . . . . .254Tryon, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Tryon, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71Tryon, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242Tsai, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Tsai, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Tsai, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Tsang, C.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Tsao, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3Tschopp, M.* . . . . . . . . . . . . . . . . . . . . . . .113, 239Tschopp, M.A. . . . . . . . . . . . . . . . . . . . .13, 55, 114Tsuchiya, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .148Tsuchiya, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .4, 39Tsujino, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Tsukada, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Tsurekawa, S. . . . . . . . . . . . . . . . . . . . . . . . . . . .183Tsurumi, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Tsutsui, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Tu, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Tu, J.J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .146Tu, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3Tu, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .271Tucker, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Tucker, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Tucker, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133Tuller, H.L. . . . . . . . . . . . . . . . . . . . . . . . . . .72, 110Tuller, H.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .110Tumne, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Tuppen, S.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .260Turner, J. . . . . . . . . . . . . . . . . . . . . . . .182, 215, 246Turner, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95Tuttle, B.A. . . . . . . . . . . . . . . . . . . . . . . . . .248, 257Tutwiler, R.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Tybell, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166Tyson, T.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .146

U

Ubic, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Uchida, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242Uchimoto, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . .110Ueda, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Uematsu, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97Ueno, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Uesugi, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Ugorek, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Ugurlu, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231Uher, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Uhlenhaut, D. . . . . . . . . . . . . . . . . . . . . . . . . . .112Ul Hasan, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .199Ulvan, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108Umarji, A.M. . . . . . . . . . . . . . . . . . . . . . . .129, 142

Umemoto, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .184Umezawa, O.* . . . . . . . . . . . . . . . . . . . . . . . . . .174Unangst, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265Unemoto, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .110Uno, M. . . . . . . . . . . . . . . . . . . . . .10, 12, 144, 206Uno, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Unuvar, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Upadhyaya, A. . . . . . . . . . . . . . . . . . . . . . .129, 135Uraki, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Uranga, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118Usman, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .176Utsuno, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Uwakweh, O. . . . . . . . . . . . . . . . . . . . . . .4, 17, 263Uwakweh, O.N. . . . . . . . . . . . . . . . . . . . . . . . . . . .4Uzomah, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .155

V

Vaithyanathan, V. . . . . . . . . . . . . . . . . . . . . . . . .262Vajram, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261Valcke, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Valera-Zaragoza, M. . . . . . . . . . . . . .5, 11, 24, 261Valiev, R.Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Valle, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Valone, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205Van Aken, D.C. . . . . . . . . . . . . . . . . . . . . . . .42, 270van Benthem, K. . . . . . . . . . . . . . . . . . . . . . . . .105van Dalen, M.E. . . . . . . . . . . . . . . . . . . . . . . . . .183van de Walle, A.* . . . . . . . . . . . . . . . . . . . . . . . .267Van de Walle, C.G.* . . . . . . . . . . . . . . . . . . . . . .107Van der Ven, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .76Van der Ven, A.* . . . . . . . . . . . . . . . . . . . . . .75, 180van Deventer, J. . . . . . . . . . . . . . . . . . . . . . .52, 125Van Every, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .126Van Iseghem, P.* . . . . . . . . . . . . . . . . . . . . . . . . .99van Laar, F.R. . . . . . . . . . . . . . . . . . . . . . . . . . . .189Vander Wal, R.L.* . . . . . . . . . . . . . . . . . . . . . . .227Vanherpe, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Varadarajan, R. . . . . . . . . . . . . . . . . . . . . . .36, 200Varanasi, C.V. . . . . . . . . . . . . . . . . . . . . . . . . . . .264Varano, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Varela, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Vargas, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4, 263Varma, S.K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Vasudevan, V. . . . . . . . . . . . . . . . . . . . . . . .244, 247Vasudevan, V.K. . . . . . . . . . . . . . .19, 203, 244, 245Vázquez, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .266Vazquez, J.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18Veal, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Venkatachar, S.K. . . . . . . . . . . . . . . . . . . . . .33, 261Ventura, J.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32Verma, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254Veronesi, P. . . . . . . . . . . . . . . . . . . . . . . . . . . .9, 143Verweij, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138Vianco, P.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Vicente Alvarez, M.A.* . . . . . . . . . . . . . . . . . . .220Vidal, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .241Viehland, D. . . . . . . . . . . . . . . . . . . . . . .29, 95, 138Viehland, D.D. . . . . . . . . . . . . . . . . . . . . . . . . . . .59Vielzeuf, D.P.* . . . . . . . . . . . . . . . . . . . . . . . . . .209Vienna, J. . . . . . . . . . . . . . . . . . . . . . .169, 170, 234Vienna, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169Vienna, J.D. . . . . . . . . . . . . . . . . . . . . . . . . . . . .234Vilenkin, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Villafuerte, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Villanueva, W.* . . . . . . . . . . . . . . . . . . . . . . . . .114Villaquiran Raigoza, C.F. . . . . . . . . . . . . . . . . . .97Víllora, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141Vincent, T.S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .232Vinci, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106Vinci, R.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 290

www.matscitech.org 291

Author Index

Vinogradov, M. . . . . . . . . . . . . . . . . . . . . . . . . .214Viswanath, R.N. . . . . . . . . . . . . . . . . . . . . . . . . . .73Viswanathan, G. . . . . . . . . . . . . . . . . . . . . . . . . . .19Viswanathan, G.* . . . . . . . . . . . . . . . . . . . . . . . .248Viswanathan, G.B. . . . . . . . . . . . . . . . . . . .117, 248Viswanathan, G.B.* . . . . . . . . . . . . . . . . . . . . . .247Viswanathan, S.* . . . . . . . . . . . . . . . . . . . .188, 228Vittayakorn, N. . . . . . . . . . . . . . . . . . . . . . . . . .142Vo, N.Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115Vogel, S.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173Vogler, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Vogt, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135Vogt, R.G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Voigt, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79Volakis, J.L. . . . . . . . . . . . . . . . . . . . . . . . . .138, 141Voorhees, P.W. . . . . . . . . . . . . . . . . . . . . . .102, 247Voyles, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140Vozdecky, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .54Vullum, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Vyas, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196

W

Wachsman, E.D. . . . . . . . . . . . . . . . . . . . . . . . . .110Wada, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Wada, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62Wagner, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128Wagner, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .182Wagner, J. . . . . . . . . . . . . . . . . . . . . . . . . . .250, 266Wagner, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Wakihara, T. . . . . . . . . . . . . . . . . . . . . . . .5, 29, 225Wakihara, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .208Walker, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Walkosz, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .69Walleser, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Walter, M.E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48Wams, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Wang, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Wang, B. . . . . . . . . . . . . . . . . . . . . . . . . . . .149, 150Wang, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33Wang, C. . . . . . . . . . . . . . . . . . . . . . . .113, 234, 235Wang, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Wang, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Wang, G. . . . . . . . . . . . . . . . . . . . . . . . .79, 151, 212Wang, H. . . . . . . . . .8, 40, 58, 62, 86, 168, 233, 264Wang, H.* . . . . . . . . . . . . . . . . . . . . . . . . . .208, 264Wang, J. . . . . . .16, 78, 130, 157, 201, 222, 261, 264Wang, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Wang, J.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Wang, J.H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Wang, J.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230Wang, K. . . . . . . . . . . . . . . . . . . . .70, 112, 162, 234Wang, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . .86, 115Wang, L. . . . . . . . . . . . . . . . . . . .151, 183, 218, 253Wang, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .204Wang, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Wang, Q. . . . . . . . . . . . . . . . . . . . . . . .183, 218, 252Wang, S. . . . . . . . . . .63, 65, 72, 134, 140, 153, 166Wang, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .45, 62Wang, W. . . . . . . . . . . . . . . . . . . . . . . . . . .105, 253Wang, W.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Wang, X. . . . . . . . . . . . . . . . . . . .5, 6, 180, 230, 259Wang, X.* . . . . . . . . . . . . . . . . . . . . . . . .77, 98, 269Wang, Y. . . .12, 16, 19, 76, 115, 165, 192, 217, 246Wang, Y.* . . . . . . . . . . . . . . .16, 113, 151, 158, 200Wang, Y.U.* . . . . . . . . . . . . . . . . . . . . . . . . .59, 186Wang, Y.W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98Wani, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Wanjara, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80Warren, J. . . . . . . . . . . . . . . . . . . . . . . . . . . .45, 254Warren, J.A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .114

Warren, J.A.* . . . . . . . . . . . . . . . . . . . . . . . . . . .240Warren, O.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Warusawithana, M. . . . . . . . . . . . . . . . . . . . . . . .62Watanabe, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .110Watanabe, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .249Watanabe, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28Watanabe, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . .271Watari, K.* . . . . . . . . . . . . . . . . . . . . . . . . . .11, 207Watcharotone, S.* . . . . . . . . . . . . . . . . . . . . . . . .87Watkins, T.R. . . . . . . . . . . . . . . . . . . . . . . . . . . .101Watson, T.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .200Watts, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132Watts, J.L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Way, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . .137, 225Weaver, J. . . . . . . . . . . . . . . . . . . .36, 166, 202, 254Weaver, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .190Weaver, M.L. . . . . . . . . . . . . . . . . . . . . . . . . . . .246Webb, B.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Weber, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .198Weber, W.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67Webster, T.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . .270Weeks, M.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . .127Wei, G.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Wei, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130, 162Wei, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111Wei, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192Wei, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Wei, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Wei, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .180Weichert, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Weidenkaff, A. . . . . . . . . . . . . . . . . . . . . . . . . . .146Weidenkaff, A.* . . . . . . . . . . . . . . . . . . . . . . . . .145Weidenmann, K. . . . . . . . . . . . . . . . . . . . . . . . .136Weil, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . .145, 198Weil, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .171, 198Weil, S.K. . . . . . . . . . . . . . . . . . . . . . . . . . .172, 206Weimer, A.W. . . . . . . . . . . . . . . . . . . . . . . . .82, 197Weissmueller, J. . . . . . . . . . . . . . . . . . . . . . . . . . .73Welk, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Welk, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164Wen, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19Wentz, J.D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .138Wereszczak, A.* . . . . . . . . . . . . . . . . . . . . . . . . . .92Werner, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .188Wessels, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .233West, A.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Weyant, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223Wheeler, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Wheeler, J.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . .257Whitbeck, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . .120White, C.E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52White, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172White, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Whitney, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187Wicker, R.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .122Wicks, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99Wieg, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Wiemhöfer, H.D.* . . . . . . . . . . . . . . . . . . . . . . .149Wiersma, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . .265Wierzbicki, A. . . . . . . . . . . . . . . . . . . . . . . . . . . .190Wilde, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .152Wildridge, G.A.* . . . . . . . . . . . . . . . . . . . . . . . .211Wilkinson, A.P.* . . . . . . . . . . . . . . . . . . . . . . . . . .46Wilks, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113Wilks, G.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55Wilks, G.B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Williams, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41Williams, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Williams, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55Williams, J.C. . . . . . . . . . . . . . . . . . . . . . . .177, 243Williams, J.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . .55

Williams, M.E. . . . . . . . . . . . . . . . . . . . . . . . . . .216Williams, R.E. . . . . . . . . . . . . . . . . . . . . . . . . . .177Willis, R.P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91Willmott, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . .185Willsey, A.G.* . . . . . . . . . . . . . . . . . . . . . . . . . . .102Wilson, J.R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102Wilson, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .191Wilson, O.C. . . . . . . . . . . . . . . . . . . . . . . . . .82, 141Wilson, O.C.* . . . . . . . . . . . . . . . . . . . . . . . .49, 222Wilson, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46Winchester, B.* . . . . . . . . . . . . . . . . . . . . . . . . . .96Windl, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160Winter, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Winter, M.R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .60Wiratmoko, A. . . . . . . . . . . . . . . . . . . . . . . . . . .237Wirth, B.D.* . . . . . . . . . . . . . . . . . . . . . . . . . .41, 70Wittstock, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .73Wojnicz, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59Wolcott, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Woldesenbet, E.* . . . . . . . . . . . . . . . . . . . . . . . .272Wolverton, C. . . . . . . . . . . . . . . . . . . .106, 107, 217Wolverton, C.* . . . . . . . . . . . . . . . . . . . . . . . . . .107Won, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28, 33Wong, P.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136Wong-Ng, W. . . . . . . . . . . . . . . . . . . . . . . . . . . .105Wong-Ng, W.* . . . . . . . . . . . . . . . . . . . . . .146, 203WongPiromsarn, K. . . . . . . . . . . . . . . . . . . . . . . .62Wood, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107Wooddell, M.* . . . . . . . . . . . . . . . . . . . . . . . . . .226Woods, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Woodward, P.M.* . . . . . . . . . . . . . . . . . . . . . . .142Wright, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .248Wright, S.L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56Wu, C. . . . . . . . . . . . . . . . . . . . . . . . . . .65, 201, 214Wu, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66Wu, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126Wu, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Wu, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .235Wu, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121Wu, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Wu, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6, 209Wu, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50Wu, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Wu, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134, 225Wu, X.* . . . . . . . . . . . . . . . . . . . . . . . . . .19, 26, 154Wynblatt, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

X

Xi, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Xi, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95Xia, G. . . . . . . . . . . . . . . . . . . . . . . . . .145, 234, 235Xia, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51Xiao, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .258Xiao, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .259Xiaoming, D. . . . . . . . . . . . . . . . . . . . . . . . . . . .269Xie, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .252Xie, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4, 230Xie, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Xie, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123Xing, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Xing, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38Xing, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138Xiong, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Xiong, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Xu, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .234Xu, D. . . . . . . . . . . . . . . . . . . . . . . . . .5, 25, 84, 238Xu, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38, 145Xu, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174, 253Xu, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Xu, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .234

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 291

MS&T’08 • October 5-9 • Pittsburgh, Pennsylvania292

Author Index

Xu, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71

Xu, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11, 204

Xue, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153

Xue, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . .251, 272

Xue, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228

Y

Yabuki, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208

Yacoby, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .185

Yadlowsky, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

Yagi, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72

Yamada, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61

Yamagisawa, K. . . . . . . . . . . . . . . . . . . . . . . . . . .19

Yamaguchi, I. . . . . . . . . . . . . . . . . . . . . . . . . . . .170

Yamaguchi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Yamaguchi, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . .72

Yamaguchi, T. . . . . . . . . . . . . . . . . . . . . . . .170, 171

Yamamoto, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .66

Yamamoto, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . .69

Yamamoto, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . .162

Yamanaka, S. . . . . . . . . . . . . . . . . .10, 12, 144, 206

Yamanaka, S.* . . . . . . . . . . . . . . . . . . . . . . . . . .206

Yamanoi, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . .154

Yamasaki, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .170

Yamasaki, M. . . . . . . . . . . . . . . . . . . . . . . . . . . .206

Yamasaki, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .100

Yamashita, M. . . . . . . . . . . . . . . . . . . . . . . . . . .242

Yamashita, T. . . . . . . . . . . . . . . . . . . . . . . . . . . .174

Yan, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139

Yan, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65, 72

Yan, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95, 120

Yan, Y. . . . . . . . . . . . . . . . . . . . . . . . . .182, 215, 246

Yanagisawa, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .25

Yanar, N.M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .144

Yanchak, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .221

Yang, F. . . . . . . . . . . . . . . . . .38, 150, 214, 215, 221

Yang, G. . . . . . . . . . . . . . . . . . . . . . . .213, 233, 243

Yang, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117

Yang, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .168, 231

Yang, J. . . . . . . . . . . . . . . . . . . . . . . . .140, 174, 209

Yang, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .67, 174

Yang, J.C. . . . . . . . . . . . . . . . .3, 181, 183, 218, 268

Yang, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .214

Yang, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

Yang, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59, 269

Yang, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .215

Yang, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251

Yang, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161

Yang, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .114, 151

Yang, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

Yang, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . .145, 235

Yang, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .234

Yanke, J.M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .127

Yao, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .229

Yao, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Yao, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66, 243

Yasuda, H. . . . . . . . . . . . . . . . . . . . . . . . . . . .14, 105

Yasuda, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61

YAsumasa, M. . . . . . . . . . . . . . . . . . . . . . . . . . .219Yasuoka, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Yausui, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61Yavuz, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162Yazdipour, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Yeager, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .268Yedidi, E.p.* . . . . . . . . . . . . . . . . . . . . . . . .131, 154Yeh, T.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Yeh, T.C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44Yen, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .215Yeo, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87Yeo, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7Yeon, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Yi, K. . . . . . . . . . . . . . . . . . . . . . . . . . . .21, 251, 252Yi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Yildiz, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72Yim, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22, 29Yin, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100Ying, Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Yiournas, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .250Yokoyama, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . .212Yoo, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17Yoo, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .243Yoo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .154Yoon, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .239Yoon, J. . . . . . . . . . . . . . . . . . . . . . . . .168, 233, 264Yoon, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Yoon, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .149Yoon, Y. . . . . . . . . . . . . . . . . . . . . .22, 169, 253, 261Yoon, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Yoshida, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218Yoshio, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Yoshiya, M.* . . . . . . . . . . . . . . . . . . . . . . . . .14, 105Yoshizawa, Y. . . . . . . . . . . . . . . . . . . . . . . . .14, 208Youchak, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . .234Youchak, A.L.* . . . . . . . . . . . . . . . . . . . . . . . . . .170Youn, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .261Young, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227Youngsman, J.* . . . . . . . . . . . . . . . . . . . . . . . . .101Yousef, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208Yu, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .240Yu, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76Yu, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192, 215Yu, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120Yu, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78Yu, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71, 168Yuan, Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Yuan, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . .202, 229Yue, S. . . . . . . . . . . . . . . . . . . . . . .80, 119, 120, 255Yuh, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Yuki, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Yun, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238Yun, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5, 240Yun, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196Yurek, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122

Z

Zacek, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119Zacherl, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .219Zako, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .242Zandbergen, H.W. . . . . . . . . . . . . . . . . . . . . . . .109Zapol, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116Zapp, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .265Zárate-Medina, J. . . . . . . . . . . . . . . . . . . . . . . . .222Zavaliche, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . .262Zavattieri, P.D. . . . . . . . . . . . . . . . . . . . . . . . . . .187Zavattieri, P.D.* . . . . . . . . . . . . . . . . . . . . . . . . .188Zeagler, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .228Zeng, Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254Zepeda-Ruiz, L. . . . . . . . . . . . . . . . . . . . . . . . . . .73

Zerrer, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .168Zhai, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138Zhang, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134Zhang, G. . . . . . . . . . . . . . . . . . . . . . . . . . .230, 254Zhang, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .180Zhang, H. . . . . . . . . . . . . . . . . . . . . . . . . . .156, 241Zhang, H.* . . . . . . . . . . . . . . . . . . . . . . . . . .78, 217Zhang, J. . . . . . . . . .53, 95, 121, 183, 258, 262, 267Zhang, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89Zhang, L. . . . . . . . . . . . . . . . . . . . . . .115, 137, 236Zhang, L.* . . . . . . . . . . . . . . .19, 138, 251, 252, 265Zhang, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104Zhang, Q. . . . . . . . . . . . . . . . . . . . . . . . . . .259, 262Zhang, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Zhang, S.* . . . . . . . . . . . . . . . . . . . . . . . .15, 30, 132Zhang, S.C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Zhang, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Zhang, V.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .260Zhang, W. . . . . . . . . . . . . . . . . . . . . . . . .28, 62, 201Zhang, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Zhang, X.* . . . . . . . . . . . . . .89, 103, 111, 117, 132Zhang, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .98, 264Zhang, Z. . . . . . . . . . . . . . . . . . .135, 136, 206, 218Zhang, Z.* . . . . . . . . . . . . . . . . . . . . . . . . .183, 256Zhao, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105Zhao, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202Zhao, Y. . . . . . . . . . . . . . . . . . . . . . . . .117, 137, 233Zhao, Y.* . . . . . . . . . . . . . . . . . . . . . . .150, 228, 244Zhe, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174Zheng, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Zheng, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Zhong, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .229Zhou, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112Zhou, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218Zhou, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .264Zhou, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Zhou, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Zhou, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151Zhou, S.H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .216Zhou, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145Zhou, Y. . . . . . . . . . . . . . . . . . . . . . . . .45, 162, 256Zhou, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227Zhou, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121Zhu, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Zhu, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13, 20Zhu, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201Zhu, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31, 132Zhu, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .129Zhu, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .209Zhu, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . .140, 217Zimmerman, M. . . . . . . . . . . . . . . . . . . . . . . . .142Znidarsic, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . .96Zok, F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .198Zolciak, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .152Zondlo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .234Zou, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Zuev, L.B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156Zumbilev, A.P. . . . . . . . . . . . . . . . . . . . . . . . . . .153Zumbilev, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . .153Zunjarrao, S.C. . . . . . . . . . . . . . . . . . . . . . . . . .224Zuo, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .251Zuogui, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . .269Zurob, H.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47Zwanziger, J.W. . . . . . . . . . . . . . . . . . . . . . .20, 117

272_292.MST_AbsAuthIndx.4th 9/3/08 3:03 PM Page 292

www.matscitech.org

Upcoming Conferences

October 2008Continuous Casting – a Practical Training Seminar 14-16 Merrillville, Indiana (AIST)ISS Aerospace Coatings Symposium 15-16 Hartford, Connecticut (ASM)Safety Conference 27-29 Pittsburgh, Pennsylvania (AIST)Cleaning Requirements for Heat Treatment-Development and Applications 29-30 Worcester, Massachusetts (ASM)

November 2008Scrap Substitutes and Alternative Ironmaking V 2-4 Baltimore, Maryland (AIST)34th International Symposium for Testing & Failure Analysis 2-6 Portland, Oregon (ASM)Making, Shaping and Treating of Steel: 101 9-12 Merrillville, Indiana (AIST)International Conference on Sintering 16-20 La Jolla, California (ACerS)

December 2008Symposium on Improving Reliability and Consistency In Thermal Spray 2-3 Montreal, Quebec (ASM)3rd International Conference on Processing Materials for Properties 7-10 Bangkok, Thailand (TMS)

January 200933rd International Conference and Exposition on 18-23 Daytona Beach, Florida (ACerS) Advanced Ceramics and Composites

February 2009Process Systems Specialty Training Conference 2-5 Jacksonville, Florida (AIST)TMS 2009 Annual Meeting & Exhibition 15-19 San Francisco, California (TMS)Modern Electric Furnace Steelmaking – a Practical Training Seminar 16-20 Ontario, California (AIST)Making, Shaping and Treating of Steel: 101 22-25 Memphis, Tennessee (AIST)Cold Rolling Fundamentals – a Practical Training Seminar 22-26 Orlando, Florida (AIST)

March 2009Lubrication Manual Seminar 16-19 Birmingham, Alabama (AIST)Ladle Refractory Short Course 17-18 Birmingham, Alabama (AIST)Hot Flat Rolling Fundamentals - a Practical Training Seminar 29-April 2 Ypsilanti, Michigan (AIST)

April 20095th International Ceramic Interconnect and 20-23 Denver, Colorado (ACerS) Ceramic Microsystems Technologies Conference4th International Brazing and Soldering Conference and Exhibition 26-29 Orlando, Florida (ASM) May 2009AISTech 2009 4-7 St. Louis, Missouri (AIST)International Thermal Spray Conference & Expo 4-7 Las Vegas, Nevada (ASM)16th Annual Crane Symposium 31-June 2 Pittsburgh, Pennsylvania (AIST)8th Pacific Rim Conference on Ceramic and Glass Technology 31-June 5 Vancouver, British Columbia (ACerS)

June 200920th Aerospace Materials & Processes Conference & Exposition 7-11 Dayton, Ohio (ASM)Electronic Materials Conference 24-26 University Park, Pennsylvania (TMS)

July 2009Microscopy & Microanalysis 26-30 Richmond, Virginia (ASM)

September 200913th International Conference on Defects – 13-17 Wheeling, West Virginia (TMS) Recognition, Imaging and Physics in SemiconductorsHeat Treating Society Conference & Exposition 14-17 Indianapolis, Indiana (ASM)International Symposium on Liquid Metal Processing and Casting 20-23 Santa Fe, New Mexico (TMS)

October 2009MS&T’09 25-29 Pittsburgh, Pennsylvania (MST)

Visit each society’s Web site for more information about these meetings:

ACerS www.ceramics.org / AIST www.aist.org / ASM www.asminternational.org / TMS www.tms.org

www.matscitech.org

The leading forum addressing structure,properties, processing and performanceacross the materials community

• Ceramic and Glass Materials• Electronic and Magnetic Materials• Environmental and Energy Issues• Fundamentals and Characterization• Iron and Steel

• Materials and Systems• Nanotechnology• Processing and Product Manufacturing• Special Topics

MS&T’09 focuses on the following nine theme areas coveringthe breadth of materials science and engineering:

Submit your abstract on one of these topics at www.matscitech.org.