Lettre Mensuelle N°111 - Réseau Français de Mécanosynthèse - Juin 2004 - Monthly Newsletter from French Mechanosynthesis Network - N°111 - June 2004

Lettre RFM N°111 Juin 2004 Corresp. : mailto:[email protected]

RESEAU FRANÇAIS DE MECANOSYNTHESE

Lettre N°111

Juin 2004

189 Groupes de Recherche

(dont 115 à l'étranger / 34 Pays)

Bureau du RFM :

E. Gaffet (Président)

G. Le Caër (Secr. Gén.), A.R. Yavari (Trés.)

International Editorial LRFM Committee

P. Balaz - Institute of Geotechnics - Slovak Academy of Sciece - Slovakia G. Le Caër - GMCM UMR CNRS 6626 - Rennes - France

A. Calka - Dpt Materials Engineering - Univ. Wollongong - Australia E. Gaffet (Coord.) - Nanomaterials Research Group - UMR 5060 CNRS / UTBM - France

S.H. Hong - Dpt Materials Science and Engineering - KAIST - Korea E. Ivanov - Tosoh - USA

M. Senna - Faculty of Science and Technology - Japan L. Takacs - Dpt Physics - Univ. Maryland – USA

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Le Prochain Rendez vous

du Réseau Français de Mécanosynthèse

en

2004

le Jeudi 15 Septembre (toute la journée)

et le Vendredi 16 Septembre 2004 (matinée) pour

Les JRFM’2004 à Bordeaux (ICMCB) Organisation locale : J.-L. Bobet (ICMCB)

Thème 2004 : Modification des Propriétés Physiques par Broyage

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Lettre RFM N°111 - Juin 2004 Corresp. : mailto:[email protected]

JRFM'2004 9 èmes Journées du Réseau Français de Mécanosynthèse

Bordeaux-Pessac (CNRS-ICMCB) - Les 16 et 17 Septembre 2004 Thématique 2004 : « Mécanosynthèse : modification des propriétés physiques et chimiques »

Fiche d'Inscription (à renvoyer à Jean-Louis BOBET le plus tôt possible et avant le 30.06.2004)

Nom : ………………………….... Prénom : ……………………………………...……………… Société : ………………………….... Téléphone :………………...…… Fax : .………….………………… E-mail : ………………….… Adresse de Facturation : ………………………………………………………………………...…... ………………………………………………………………………..…….………………………. Ø Pour les laboratoires propres ou associés au CNRS, indiquer le code et l’adresse complète de l’Unité. Une facture sera établie

directement à leur encontre. Ø Pour les agent CNRS merci d’indiquer votre indice majoré : ………………

(Nécessaire pour obtenir un discount pour les déjeuners !) Frais d’inscription : (comprenant : recueil des résumés, 2 déjeuners, 1 dîner) Déjeuner du 16 septembre oui / non

Dîner du 16 septembre oui / non (Prière d'entourer les réponses) Déjeuner du 17 septembre oui / non

Tarifs : permanents 65 euros, étudiants 20 euros Mode de paiement :

Ø Dès réception du bullet in d’inscript ion dûment complété par vos soins (ou d’un bon de commande de votre organisme), une facture sera établie pour paiement : aucun règlement n’est à effectuer à l ’ inscription .

Ø Rappel : le CNRS gérant ce colloque, i l est fortement conseil lé de privi légier le paiement par virement administrat i f du CNRS.

Conditions de résiliation : En cas de désistement, aucun règlement ne sera restitué. ""-------------------------------------------------------------------------------------------------------------------------

Fiche d'inscription et résumés à retourner le plus tôt possible et avant le 30/06/2004 à : Jean-Louis BOBET (Journées RFM2004)

CNRS - Institut de Chimie de la Matière Condensée de Bordeaux Av du Dr A. Schweitzer - 33608 Pessac Cedex

(Tel : 05.40.00.26.53 - fax : 05.40.00.27.61, E-mail : [email protected]) Date limite d’Envoi des Résumés : 14 juillet 2004

Possibilité de soumettre un article. Après sélection, les articles proposés pourront être publiés dans : Journal of Metastable and Nanocrystalline Materials (J. Metastable & Nano. Mater. - Trans Tech Publ.)

Editors : A.R. Yavari, A. Inoue, R. Schulz, D. Morris Int. Editorial Board, : J.H. Ahn, H. Bakker, M.D. Baro, R. Bormann,, A. Calka, G. Cocco, J. Eckert,

E. Gaffet, S. Gialenella, A. Hernando,, A. Inoue, C. Koch, G. Le Caer, M. Magini, D. Morris, P.H. Shingu,, L. Schultz, R. Schulz

IMPORTANT : Les frais d'inscription ne comportent pas l'adhésion au RFM au titre de l’année 2004. Pour participer aux JRFM2004, il est impératif d’envoyer votre cotisation à l’ordre du RFM. (Pour tout renseignements complémentaires sur cette adhésion contacter E. Gaffet).

Comité d’organisation Jean-Louis Bobet et toute l’équipe

“Détermination structurale et matériaux magnétiques”

CNRS - ICMCB (UPR 9048 CNRS - Université Bordeaux1)

Av du Dr A. Schweitzer, 33608 Pessac Cedex. Tel : 05.56.84.26.53 - Fax : 05.56.84.24.80

E-mail : [email protected]

Eric Gaffet Président du Réseau Français de Mécanosynthèse

NanoMaterials Research Group – UMR 5060 CNRS

Université de Technologie de Belfort - Montbéliard -UTBM

Site de Sévenans – 90010 Belfort Cedex. Tél : 03 84 58 31 02 - Fax : 03 84 58 30 27

E-mail : [email protected]

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Extrait du site Web de la société Fritsch

(http://www.fritsch.de).

Contact : [email protected]

Fritsch GmbH Manufacturers of Laboratory Instruments Industriestraße 8 - D-55743 Idar-Oberstein - Germany Phone: +49/67 84/70-0 / Fax: +49/67 84/70-11

Le broyeur Vario - Mill est la version commercialisée du broyeur G5 développé par E. Gaffet

technical data Electrical details: 400 V/3 Frequency: 50-60 Hz input power: 9000 W Working Principle: impact force Interface: RS232 Timer: 99 min.

Over All Dimensions (WxDxH):

600x800x1100 mm

Weight net: 320 kg Weight gross: 380 kg Max. feed size: 10 mm Feed quantity: up to 2 x 225 ml attainable final fineness: < 1 µm suitable for the following sample materials hard: yes medium hard: yes soft: yes brittle: yes tough: yes fibrous: yes temperatur-sensitive: yes

Vario-Planetary Mill "pulverisette 4 description A Planetary Mill with infinitely variable grinding conditions and therefore the ideal mill for mechanical activation and alloying. The main applications are in the field of materials research and, of course, wherever a powerful, innovative planetary mill is required. Typical fields of application: The "pulverisette 4" vario-planetary mill is capable of emulating ball mills of conventional design, precisely simulating the types of stress entailed and thus reproducing or optimising grinding processes. Method of operation: But with the "pulverisette 4" vario-planetary mill the rotational speeds of grinding bowls and supporting disc can be adjusted completely independently of each other in contrast to standard planetary mills. By changing the transmission ratio it is therefore possible for the first time to carry out mechanical activation as well as mechanical alloying. Features of performance: - free selectable, controlled rotation speed for grinding bowls and supporting disc - Programming of the grinding parameters by PC software as desired - RS232 interface for programming and to transfer grinding parameters to the PC - Real-time display of the speeds to monitor the grinding process - Reversing option to improve the grinding results - Emulation of various ball mills - Variably adjustable pressure on sample (friction and/or impact) - Simultaneous grinding in up to 4 small or 2 large grinding bowls - Quick, secure fastening of the grinding bowls "safe lock" Equipment: The Vario-Planetary Mill "pulverisette 4" is equipped with 2 bowl fasteners and a "safe lock" clamping system. This mill is delivered without grinding bowls and balls, which are available in 9 different materials and must be ordered as accessories.

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================================================= Bulletin d'adhésion au RFM 2004 / 2004 RFM Subcription Print

(à retourner à l'adresse suivante - to be sent at the following address) : Eric GAFFET

CNRS UMR5060 « Métallurgies et Cultures » Nanomatérials Research Group

Site de Sévenans (UTBM) -F90010 - Belfort Cedex - France Nom/Name : .........................................Prénom / First Name : .................................. Adresse complète / Full Address : .................................................................................... Téléphone/ Phone: ................................Télécopie (Fax) : ................................. e_Mel. / e-Mail : ....................................................................................... désire adhérer au Réseau Français de Mécanosynthèse / want to become a member of the French Mechanical Alloying Network Chèque ci joint / Check enclosed in the amount of 20 Euros (20€) The check has to be to the order to : Reseau Francais de Mecanosynthèse

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Le site web du RFM est : http://www.bls.fr/amatech

Rubrique Pages Sciences et Techniques pour l'Ingénieur (Rubrique Sciences) ⇒ vous y trouverez les anciennes lettres du RFM (accessible par Adobe Acrobat),les statuts du RFM ainsi que les annonces concernant les JRFM'2001 et quelques éléments mis a jour régulièrement concernant les derniers résultats dans ce domaine.

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================================================= Congress and School Announcements

================================================= 5th International Conference on Magnetic Microspheres,

May 20-22, 2004 Ecole Normale Supérieurede Lyon, Lyon, France

Contact: U. Haefeli & M. Zborowski, W. Schuett; and S. Legasteloi EMail: [email protected];

EMail: [email protected] WebSite: http://www.magneticmicrosphere.com

- - - - - - - - - - - - - - - - - - - - - - - Spring College on Science at the Nanoscale,

May 24-June 11, 2004 Abdus Salam Intenational Centre for Theoretical Physics, Trieste, Italy

Contact: EMail: [email protected], WebSite: http://agenda.ictp.trieste.it/smr.php?1564

- - - - - - - - - - - - - - - - - - - - - - - Symposium on Modeling and Simulating Materials Nanoworld, 3rd International Conference on

Computational Modeling and Simulation of Materials, May 30 - June 4, 2004

Acireale (Cantania), Sicily, Italy Contact: Cimtec

WebSite: http://www.technagroup.it/modeling.htm - - - - - - - - - - - - - - - - - - - - - - -

Nanotechnology in Biology, Biotechnology, and Medicine, 5th CAMD Summer Workshop,

Center for Advanced Microstructures & Devices, May 31-June 4, 2004

Louisiana State University, Baton Rouge, Louisiana Contact: CAMD

EMail: [email protected] WebSite: http://www.camd.lsu.edu

- - - - - - - - - - - - - - - - - - - - - - - Mechanochemical Synthesis and Sintering

14 - 18 Juin 2004 Contact Prof. N. Lyakhov

E_mail : mailto:[email protected] WEBSitehttp://www.solid.nsc.ru/ - - - - - - - - - - - - - - - - - - - - - - -

International Conference on Fabrication and Properties of Metallic Nanomaterials June 17-19, 2004 Warsaw, Poland

Contact: D. Oleszak, EMail: [email protected],

WebSite: http://www.nanocentre.inmat.pw.edu.pl/events/konferencja.php - - - - - - - - - - - - - - - - - - - - - - -

NANO 2004 7th (Biennial) International Conference on Nanostructured Materials,

June 20-24, 2004 Wiesbaden, Germany

Contact: B. Feisst, EMail: [email protected]

WebSite: http://www.nano2004.org - - - - - - - - - - - - - - - - - - - - - - -

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Second Seeheim Conference on the Magnetism of Nanostructured Materials, June 27-July 1, 2004

Lufthansa Training Centre, Seeheim, Germany Contacts: M. Ghafari & H. Hahn,

EMail: [email protected] WebSite: http://www.tu-darmstadt.de/magnetism

- - - - - - - - - - - - - - - - - - - - - - - 8th International Conference on Nanometer-Scale Science and Technology (NANO-8),

June 28-July 2, 2004 Cinema Festival Palace, Venice, Italy

Contact: EMail: [email protected] WebSite: http://www.ivc16.org - - - - - - - - - - - - - - - - - - - - - - -

Topical Meeting of the European Ceramic Society on "Nanoparticles, Nanostructures, & Nanocomposites" (NNN-2004),

July 5-7, 2004 St. Petersburg, Russia Contact: NNN-2004

EMail: [email protected] WebSite: http://www.isc.nw.ru/Eng/index.htm

- - - - - - - - - - - - - - - - - - - - - - - LAM 12

the Twelfth International Conference on Liquid and Amorphous Metals Metz (France) - 11-17 July 2004.

The main LAM12 site with general information: http://lam12.sciences.univ-metz.fr/

mailto:[email protected] - - - - - - - - - - - - - - - - - - - - - -

ISMANAM 11 22-26 août 2004

Sendai, WebSite : http://www.ismanam2004.imr.edu/

- - - - - - - - - - - - - - - - - - - - - - - Nanocomposites 2004,

September 1-3, 2004 Crowne Plaza Hotel, San Francisco, California Contact: Executive Conference Management

EMail: [email protected] WebSite: http://www.executive-conference.com/conferences/nano04.html

- - - - - - - - - - - - - - - - - - - - - - - Session N on Nanostructured Materials, Junior Euromat 2004,

September 6-9, 2004 Swiss Federal Institute of Technology, Lausanne, Switzerland

Contacts: A. Mangold & B. Toelle, EMail: [email protected]

WebSiteE: http://www.junior-euromat.fems.org - - - - - - - - - - - - - - - - - - - - - - -

Symposia A, G & I on Nanomaterials and Nanotechnology, European Materials Research Society Fall Meeting,

September 6-10, 2004 Warsaw University of Technology, Warsaw, Poland Contacts: J. Morante, R. Piticescu & U. Narkiewicz

EMail: [email protected]; EMail: [email protected];

EMail: [email protected] WebSite: http://www.e-mrs.org/fall2004

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"Miniaturization & Nanotechnology in PM" Sessions, Powder Metallurgy World Congress & Exhibition (PM2004),

October 17-21, 2004 Austria Centre, Vienna, Austria

Contact: EPMA Secretariat (Euro PM 2004) EMail: [email protected]

- - - - - - - - - - - - - - - - - - - - - - - Les Premières Journées de la Fédération Française des Matériaux Allègement des Structures – Traitements et Revêtements de Surface

26 – 28 Octobre 2004 Limoges – France

WebSite : http://www.ffmateriaux.org - - - - - - - - - - - - - - - - - - - - -

European Micro and Nano Systems 2004 (EMN04), October 20-21, 2004

ESIEE, Noisy le Grand (Paris), France (Contacts: D. Fruman, 16 Allee Bellevue, 78230 Le Pecq, France, FAX: +33-1-39170013, EMAIL:

[email protected]; J. Fabri, Secretaire General du GST/MIA, Paris, France, EMAIL: [email protected]; B. Courtois, TIMA-CMP, Grenoble, France, EMAIL: [email protected]; and R.

Manchanda, ASME Nanotechnology Institute, New York City, New York, EMAIL: [email protected]; WEBSITE: http://tima.imag.fr/conferences/emn)

- - - - - - - - - - - - - - - - - - - - - - - Sessions on Multiscale Computing and Nanotechnology and on Mechanics on the Nanoscale,

ASME November 13-19, 2004 Winter Annual Meeting, Anaheim, California

(Contact: ASME, WEBSITE: http://www.asmeconferences.org/Congress04/index.cfm) - - - - - - - - - - - - - - - - - - - - - - -

International Congress of Nanotechnology November 14-18, 2004

Hyatt Regency Hotel, San Francisco, California (Contact: Secretariat, International Association of Nanotechnology, 2386 Fair Oaks Blvd., Sacremento,

CA 95825, FAX: 916-424-1650, EMAIL: [email protected], WEBSITE: http://www.nanotechcongress.com)

- - - - - - - - - - - - - - - - - - - - - - - International Workshop on Nanomagnetism,

November 14-18, 2004 Monastery of San Francisco de Asis, Havana, Cuba

EMAIL: [email protected], WEBSITE: http://www.nanomagnetics.org)

- - - - - - - - - - - - - - - - - - - - - - - Thirteenth International Conference on Processing and Fabrication of Advanced Materials (PFAM

XIIIDecember 6-8, 2004 National University of Singapore, Singapore

(Contact: Secretariat, EMAIL: [email protected], WEBSITE: http://serve.me.nus.edu.sg/pfam13) - - - - - - - - - - - - - - - - - - - - - - -

Smart Materials, Nano-, and Micro-Smart Systems, SPIE International Symposium December 12-15, 2004

,University of New South Wales, Sydney, Australia

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Post Doc Position and/ or Contract Proposal

From E. Gaffet (on the 5/5/2004) PostDoc Position Opportunities

Post Doc Position(s) will be opened in the field of Mechanosynthesis of NanoParticles (EUREKA Program) at NRG / CNRS lab (Belfort). Mobility in France / Europe will be also required.

Ideally, the successful candidate will possess a thesis in nanomaterials related discipline, ideally have knowledge of nanopowder metallurgy processing and nanostructure characterizations (XRD, SEM / EDX, TEM)

Applicants should submit a comprehensive CV accompanied by a motivation letter to ; Eric Gaffet – NanoMaterials Research Group – UMR 5060 CNRS / UTBM – F90010 Belfort Cedex – France or via email : [email protected] From Ch. Gras (on the 26/03/2004) Graduate / Postgraduate Opportunity in Powder Group CERAM is an internationally renowned Centre of Excellence in materials and their processing. We have a unique and exciting opportunity for a high calibre graduate/post-graduate to join our Powder Group, supporting and developing areas of technical and commercial importance such as:

• Hydrogen storage in hydrides • Quasicrystal and metallic glass processing • High strength permanent magnet processing

The initial contract will be for two years, with the possibility of a permanent post being offered should the expected potential of this venture be realised. The successful applicant will possess a degree in a materials related discipline, ideally have some knowledge of powder metallurgy, rapid solidification, hydrides, magnets and/or quasicrystals, and possess the personal qualities necessary to make a major contribution to these projects and their commercial exploitation. Applicants should submit a comprehensive CV accompanied by a letter of application and detailing their current salary to Miss Julie Parker, HR Administrator, CERAM, Queens Road, Penkhull, Stoke-on-Trent, Staffordshire ST4 7LQ or via email at: [email protected] From Ch. Gras (on the 23/02/2004)

QinetiQ Innovation is a way of life Advanced Materials Analyst · Malvern, Worcestershire £18,000 to £25,000 (further remuneration available for exceptional candidates)

4000 patents testify to the imagination and ingenuity of QinetiQ: creators of cutting-edge technology from radar to liquid crystal displays, carbon fibre to infrared sensors. Formerly part of MOD's research organisation, we are now a commercial force to be reckoned with across technologies, market sectors and geographic borders.

Joining an expert team, you will provide materials analysis and advice to internal and external customers - delivering measurements, consultancy and solutions that meet technical, timeframe and budgetary needs. Projects will be varied and fast moving so you will enjoy constant challenges and stimulation, and your customer service, communication and technical skills will be tested to the full. Qualified to Honours Degree or PhD level in an appropriate discipline, you will have experience of instrumental analysis techniques such as SEM, SIMS, XRD, TEM and AFM as well as an awareness of advanced materials gained from your background in academia or the electronics, semiconductor or scientific industries.

Above all, you will enjoy working on your own initiative, and earning respect as an organisation-wide expert on materials and techniques.

In return, you can expect an industry-leading reward package, investment in your personal and skills development, and all the scope you need to build and further your career.

Please visit www.QinetiQ.com/careers to apply. In the 'Jobs at QinetiQ' section search for this vacancy, ref 11998 and complete the online application form. Alternatively, you can request an application form by calling 01980 664030, or writing to QinetiQ HR, QinetiQ, Room C001, Bldg 416, QinetiQ Boscombe Down, Salisbury, Wiltshire SP4 0JF. Closing date is 26 February 2004.

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Looking for Post-doc Position Dr. JI Gang E-mail: [email protected] Training of Ph.D. (Sep. 2000~Dec. 2003) Laboratoire de Métallurgie Physique et Génie des Matériaux (LMPGM, UMR CNRS 8517) in Université des Sciences et Technologies de Lille (USTL) and Laboratoire d’Etude et de Recherche sur les Matériaux et les Propriétés de Surface (LERMPS, EA 3316) in UTBM,the main research work including the study of elaboration and characterization ofnanocrystalline Fe-40Al coatings prepared by thermal spraying of milled powders, test the feasibility of spray-forming thick nanocrystalline deposits as well as the study of thermal stability of milled powders and nanostructured coatings. Competent Fields • 7 years’ work in Materials science, Physical metallurgy and Surface engineering(Experience of Nanomaterials (powders, coatings or bulk pieces) prepared by Mechanical alloying/consolidation, Rapid solidification/annealing or Thermal spraying/spray forming) • Rich experience in the study of microstructure by Scanning and Transmission Electronic Microscopy (micro- and nano-analysis, microdiffraction, CBED), X-rays diffraction (Profile analysis, quantitative analysis), Mössbauer spectrometry, Image analysis, Thermal analysis (DSC, DTA), etc. • Master of the software “Electron Diffraction” for simulation of various diffraction (point, ring or line) patternsas well as the techniques for preparation of different powder and coating thin foils. Publications Ten articles published in the international journals and three articles published for the conferences Professional version I hope to find one suitable occupation where I can make best use of my skills, abilities and knowledge, especially, my experience of nanomaterials preparations and TEM characterization. I also hope that the further work can bring me to some other fields concerning the mechanical and chemical properties of nanomaterials to finally access its applications. (I will be available since March 2004)

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Looking for Post-doc Position (suite) Grégory SAINT-AYES 171, avenue du Général Leclerc, Bât. A 91190 GIF SUR YVETTE 33 (0)1 69 08 89 88 mailto:[email protected] 26 years, single Free 02/2004 Dear Sir or Madam, I’m PhD student in Materials Sciences.

My PhD’s subject is “Wear of high speed train wheels : a driven alloys approach” I have studied the formation of circularity defect (Appearance of Localized Flattening: ALF)

affecting the rolling strip of train wheels. The metallurgical study of the rolling strip shows the formation of a white layer and a brown layer, with very different properties than those of the pearlitic steel, and allows us to propose a cyclic wear mechanism that leads to the formation of ALF. High energy ball milling were used to reproduce the same metallurgical transformations than those observed at the surface of the wheel. So, we can test steel powder of different compositions to determine the best one.

My abilities are : Materials sciences, metallurgical characterization of steels (optical microscopy,

scanning and transmission electron microscopy, X-ray diffraction, Mössbauer spectrometry, nanoindentation, image analysis method, dilatometry), mechanical testing, contact mechanics, surface treatment, high energy ball milling (vibrating frame single ball grinder).

I’m looking for a post-doc in a foreign country, mainly in Canada and USA but also in other country. I’d like to work on elaboration process (for example mechanosynthesis, super plastic deformation, …), or assembling process ( form example friction stir welding, …), or manufacturing process in relation with industry. It could be with metallic materials, like steel, aluminium, titanium alloys, manganese alloys, …

For more informations, you can contact me or E. Gaffet. Yours faithfully

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Bibliographie (Ouvrage)

Le procédé SPS (Spark Plasma Sintering ) Auteur : E. Gaffet Editeur Innovation 128 - ISBN : 2-906024-31-7 - Janvier 2004 - 152 pages

(Innovation 128 – 24 rue du Quatre Septembre – 75002 Paris – France – Fax : (+33) 1 42 65 47 76) Press Release :

SeptembrLa mise en oeuvre des courants pulsés de fortes intensités (jusqu’à 10.000 Ampères) sous faibles tensions (inférieure à quelques centaines de Volts) permet d’élargir les capacités de la métallurgie des poudres (consolidation de matériaux hétérogènes & frittage réactif), du soudage / jonction et des traitements de surface.

Le procédé SPS permet de densifier / consolider des matériaux tout en leur conservant leurs caractéristiques initiales (microstructures, nanostructures). Si les durées de mise en oeuvre des procédés de densification classiques s’élèvent plutôt en heures, le procédé SPS permet de consolider des matériaux pour des durées se chiffrant en minutes. Il permet également dans le domaine du frittage de consolider des matériaux poreux (macro et microporosité).

Les domaines d'applications des machines SPS couplant décharge électrique (jusqu'à 8.000 A / 0 - 10 V) et pressions (jusqu'à 500 Tonnes pour les machines industrielles) sont le frittage réactif ou non des nanomatériaux (en conservant l'échelle nanométrique), des composites à matrice métallique et / ou des cermets, des composés intermétalliques, des matériaux thermoélectriques ou la réalisation de matériaux à gradients ou de céramiques renforcées par des fibres ainsi que le frittage de composants aussi différents que polymères /métaux.

Dans le domaine du soudage / jonction, ce type de procédés permet de lier des matériaux réputés difficilement soudables. Ces matériaux peuvent se présenter sous forme de poudres et/ou de feuillards.

Dans le domaine des traitements de surface, ils permettent par exemple de modifier la densité superficielle de revêtements et /ou la porosité de surface.

Au début 2003, on comptait déjà 150 machines commercialisées au Japon mais seulement deux en Europe (Stockholm et Dresde) et une seule aux Etats-Unis pour des applications dans les domaines tels que les outils de coupe (WC avec ou sans Co), l'industrie automobile (densification de pièces à bas d'Al), l'aéronautique (mise en forme d'alliages spéciaux), les composites renforcés, l'optique (densification de céramiques transparentes), la thermique (matériaux à gradients) et la biologique (biocéramiques). Il aura fallu attendre ce printemps 2004 pour qu’une première machine soit installée en France.

Un état de l’art exhaustif est établi et une analyse de près d’une centaine de brevets vient compléter ce rapport. Cette étude très documentée est rédigée par l'un des meilleurs spécialistes européens des nanomatériaux et de la mécanosynthèse qui a été personnellement amené à mettre en oeuvre le procédé SPS. En contact étroit avec les acteurs internationaux du domaine SPS, l'auteur livre des informations qui vous permettront d'évaluer sans retard les avantages de cette nouvelle technologie dans vos applications.

Sommaire

1 - Introduction 1.1. historique 1.2. références

• 2 - Principe du procédé Spark Plasma Sintering 2.1. description du dispositif 2.2. mécanismes de densification 2.3. paramètres intrinsèques au procédé

- modulation du courant électrique - effet de la pression - effet de la durée de maintien à la température de frittage.

2.4. paramètres extrinsèques au procédé SPS 2.5. modélisation 2.6. références

• 3 - Consolidation 3.1. consolidation des matériaux métalliques

- consolidation d’éléments purs - références

3.2. consolidation des matériaux inorganiques - oxydes - carbures - nitrures - borures - carbol-nitrures- oxy-nitrures - boro-nitrures - boro-carbures - références

3.3. consolidation de matériaux organiques - polyéthylène et polypropylène - références

• 4 - Mise en oeuvre du procédé SPS pour la soudure de constituants conduisant à la réalisation de composites mono - directionnels

4.1. réalisation de composites 1 D à partir de feuillards 4.2. réalisation de composites 1 D à partir de poudres élémentaires 4.3. références

• 5 - Traitements de surface avec l’aide du procédé SPS

5.1. matériaux biocompatibles 5.2. matériaux à base de ZrO2 5.3. références

• 6 - Brevets de référence - portant sur la consolidation et/ou le frittage - portant sur le soudage/jonction - portant sur les revêtements - portant sur les matériaux à gradient - portant spécifiquement sur le procédé

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Bibliographie (Périodiques et Actes de Congrès)

Health and Risks related to NanoMaterials

PULMONARY TOXICITY OF SINGLE-WALL CARBON NANOTUBES IN MICE 7 AND 90 DAYS AFTER INTRATRACHEAL INSTILLATION Lam CW, James JT, McCluskey R, Hunter R - TOXICOLOGICAL SCIENCES - 77 (1): 126-134, JAN 2004 - 42nd Annual Meeting of the Society-of-Toxicology - SALT LAKE CITY, UTAH, MAR 09-13, 2003 Nanomaterials are part of an industrial revolution to develop lightweight but strong materials for a variety of purposes. Single-wall carbon nanotubes are an important member of this class of materials. They structurally resemble rolled-up graphite sheets, usually with one end capped; individually they are about 1 nm in diameter and several microns long, but they often pack tightly together to form rods or ropes of microscopic sizes. Carbon nanotubes possess unique electrical, mechanical, and thermal properties and have many potential applications in the electronics, computer, and aerospace industries. Unprocessed nanotubes are very light and could become airborne and potentially reach the lungs. Because the toxicity of nanotubes in the lung is not known, their pulmonary toxicity was investigated. The three products studied were made by different methods and contained different types and amounts of residual catalytic metals. Mice were intratracheally instilled with 0, 0.1, or 0.5 mg of carbon nanotubes, a carbon black negative control, or a quartz positive control and euthanized 7 d or 90 d after the single treatment for histopathological study of the lungs. All nanotube products induced dose-dependent epithelioid granulomas and, in some cases, interstitial inflammation in the animals of the 7-d groups. These lesions persisted and were more pronounced in the 90-d groups; the lungs of some animals also revealed peribronchial inflammation and necrosis that had extended into the alveolar septa. The lungs of mice treated with carbon black were normal, whereas those treated with high-dose quartz revealed mild to moderate inflammation. These results show that, for the test conditions described here and on an equal-weight basis, if carbon nanotubes reach the lungs, they are much more toxic than carbon black and can be more toxic than quartz, which is considered a serious occupational health hazard in chronic inhalation exposures.

Mechanosynthesis references

[115] NANOPOROUS INORGANIC MATERIALS FROM MINERAL TEMPLATES MacKenzie-KJD; Okada-K; Temuujin-J - CURRENT-APPLIED-PHYSICS. APR 2004; 4 (2-4) : 167-170. The crystal architecture of layer-lattice minerals has been used to prepare inorganic materials containing pores of closely controlled size and shape. The template minerals are activated, either by thermal or mechanical treatment, and selectively leached with acid to remove the octahedrally-coordinated component, or with alkali to remove the tetrahedral (silica) component. Some acid-leached products contain hydrophilic slit-shaped pores with narrow size distributions typically in the nanopore range, whereas the alkali-leached products contain unimodal pore distributions of larger size (2-3 nm). The leaching by-products have also been used to Pip prepare combined anion and cation exchange material potentially useful for simultaneous removal of PO4- and NH4+ from waste waters. [114] DIELECTRIC BEHAVIORS OF PB1-3X/2LAXTIO3 DERIVED FROM MECHANICAL ACTIVATION Soon-HP; Xue-JM; Wang-J - JOURNAL-OF-APPLIED-PHYSICS. MAY 1 2004; 95 (9) : 4981-4988. To investigate the origin of ultrahigh relative permittivity that has been observed for lanthanum-doped lead titanate, Pb1-3x/2LaxTiO3 (PLT-A) with x ranging from 0.10 to 0.25 were synthesized by mechanical activation of constituent oxides. Their sintered density, grain size and relative permittivity demonstrated a steady increase with increasing of La doping. Upon thermal annealing in oxygen, the relative permittivity of Pb0.70La0.2TiO3 (PLT-A20) at T-c showed an initial rise and a peak at 4h of annealing, and then a steady fall with further increase in annealing time. In contrast, when annealed in nitrogen for 4 h, a significant rise in relative permittivity was observed, although the increase rate falls with prolonged annealing. The observed dependence of relative permittivity and dielectric loss for PLT-A20 on the initial annealing in both oxygen and nitrogen demonstrated the domination of space charge polarization as a result of PbO loss through evaporation from the surface region. While the high activation energy for Pb2+ and O2- diffusion through the surface scale slows down the rate of PbO loss through evaporation, excess loss of PbO adversely affect space charge polarization, leading to a fall in relative permittivity of PLT-A20, upon prolonged annealing in oxygen. In addition to PbO loss, prolonged annealing in nitrogen generated oxygen vacancies, which played an important role in affecting the relative permittivity. [113] THE EFFECTS OF SHOCK ACTIVATION ON SINTERING SI3N4 CERAMICS Lu-FY; Cai-QY; Lu-L; Zhang-ZY; Wang-ZB - JOURNAL-OF-MATERIALS-PROCESSING-TECHNOLOGY. MAR 30 2004; 147 (1) : 90-93. Si3N4 powder was activated under several shock-wave pressures by using an explosion driven flyer impact technique. The powders had been sintered to ceramics under hot-pressing conditions during the subsequent processing. Features of the

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ceramics sintered from the both activated powders and original powders had been observed by SEM, TEM and XRD. Comparison of structures and mechanical properties of the ceramics showed that, the best comprehensive mechanical properties had been obtained for ceramics sintered at 1800 degreesC from around 40 GPa shock-wave activated powders. Bending strength and shock toughness of the ceramics were about 40-50% higher than that in the normal case. It means that the shock activation can enhance the ceramics properties with convenience and lower cost. [112] ABRASIVE-REACTIVE MECHANOCHEMICAL SYNTHESIS OF COHENITE WITH THE APPLICATION OF DIAMOND Urakaev-FK; Pal'-yanov-YN; Shevchenko-VS; Sobolev-NV- DOKLADY-EARTH-SCIENCES. FEB-MAR 2004; 395 (2) : 214-218. [111] DYNAMIC RHEOLOGICAL PROPERTIES OF HIGH-DENSITY POLYETHYLENE/POLYSTYRENE BLENDS EXTRUDED IN THE PRESENCE OF ULTRASONIC OSCILLATIONS Chen-GS; Guo-SY; Li-YT - JOURNAL-OF-APPLIED-POLYMER-SCIENCE. JUN 5 2004; 92 (5) : 3153-3158. The linear rheological properties of high-density polyethylene (HDPE), polystyrene (PS), and HDPE/PS (80/20) blends were used to characterize their structural development during extrusion in the presence of ultrasonic oscillations. The master curves of the storage shear modulus (G') and loss shear modulus (G") at 200degreesC for HDPE, PS, and HDPE/PS (80/20) blends were constructed with time-temperature superposition, and their zero shear viscosity was determined from Cole-Cole plots of the out-of-phase viscous component of the dynamic complex viscosity (eta") versus the dynamic shear viscosity. The experimental results showed that ultrasonic oscillations during extrusion reduced G' and G" as well as the zero shear viscosity of HDPE and PS because of their mechanochemical degradation in the presence of ultrasonic oscillations; this was confirmed by molecular weight measurements. Ultrasonic oscillations increased the slopes of log G' versus log G" for HDPE and PS in the low-frequency terminal zone because of the increase in their molecular weight distributions. The slopes of log G' versus log G" for HDPE/PS (80/20) blends and an emulsion model were used to characterize the ultrasonic enhancement of the compatibility of the blends. The results showed that ultrasonic oscillations could reduce the interfacial tension and enhance the compatibility of the blends, and this was consistent with our previous work. [110] SYNTHESIS, REACTIVE MECHANISM AND THERMAL STABILITY OF W1-XALXC (X=0.33, 0.5, 0.75, 0.86) NANOCRYSTALLINE Tang-HG; Ma-XF; Zhao-W; Yan-XW; Yan-JM - MATERIALS-RESEARCH-BULLETIN. APR 2 2004; 39 (4-5) : 707-713. W1-xAlxC (x = 0.33, 0.50, 0.75, 0.86) solid solutions have been synthesized directly by ball-milling tungsten powder, aluminum powder and activated carbon. The structural development of W0.5Al0.5C phase with the milling times up to 160 h has been followed using X-ray diffraction. X-ray photoelectron spectra demonstrate that Al atom takes the place of W. High temperature annealing experiment reveals that Al is stable in hexagonal structure to 1873 K. Transmission electron microscopy image shows that the grain size of the prepared powders is about 5 nm. [109] ELECTROCHEMICAL AND INTERFACIAL PROPERTIES OF (PEO)(10)LICF3SO3-AL2O3 NANOCOMPOSITE POLYMER ELECTROLYTES USING BALL MILLING Shin-JH; Jung-BS; Jeong-SS; Kim-KW; Ahn-HJ; Cho-KK; Ahn-JH - METALS-AND-MATERIALS-INTERNATIONAL. APR 2004; 10 (2) : 177-183. Electrochemical and interfacial properties of (PEO)(10)LiCF3SO3-Al2O3 composite polymer electrolytes (CPEs) prepared by either ball milling or stirring are reported. Ball milling was introduced into a slurry preparative technique utilizing PEO lithium salt and Al2O3 powder ranging from 5 to 15 wt.%. The ionic conductivity was increased by ball mulling over a range of temperatures. In particular, a significant increase at low temperature below the melting point of crystalline PEO was observed. Interfacial stability between lithium electrode and CPE was significantly improved by the addition of alumina as well as by ball milling. The electrochemical stability window produced by (PEO)(10)LiCF3SO3-Al2O3 ball milling was higher than that of stirring, which was about 4.4 V. Charge/discharge performance of Li/CPE/S cells with (PEO)(10)LiCF3SO3-Al2O3-12 hr ball milling was superior to that of a pristine polymer electrolyte due to the low interface resistance and high ionic conductivity. [108] TOPOLOGICAL AND CHEMICAL ARRANGEMENT OF BINARY ALLOYS DURING SEVERE DEFORMATION Lund-AC; Schuh-CA - JOURNAL-OF-APPLIED-PHYSICS. MAY 1 2004; 95 (9) : 4815-4822. We explore the alloy structures that can evolve in nonequilibrium driven systems, using two-dimensional atomistic simulations of mechanical alloying. By tailoring the intrinsic system thermodynamics we demonstrate the evolution of alloys with various states of topological and chemical ordering, including random solid solutions with both crystalline and amorphous topology, short-range ordered glasses and crystals, and segregated dual-phase systems. Our observations are broadly consistent with the experimental literature for mechanical alloying of binary systems. Further, while most of our results can be rationalized on the grounds of existing theories for either (i) glass formation and stability or (ii) nonequilibrium systems under external driving, we also observe strong correlations between topological and chemical ordering which have not yet been addressed in the context of driven systems. [107] EFFECT OF ECAP STRAIN ON DEFORMATION BEHAVIOR AT LOW TEMPERATURE SUPERPLASTIC REGIME OF ULTRAFINE GRAINED 5083 AL ALLOY FABRICATED BY ECAP Park-KT; Lee-HJ; Lee-CS; Du-Ahn-B; Cho-HS; Shin-DH - MATERIALS-TRANSACTIONS. MAR 2004; 45 (3) : 958-963.

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A series of tensile testing was carried out on the ultrafine grained 5083 Al alloy, which was fabricated by equal channel angular pressing (ECAP) with different ECAP strains, at low temperature superplastic (LTS) temperature of 548 K. This investigation was aimed at examining the effect of the ECAP strain inducing different microstructure in the alloy on the deformation mechanisms at LTS regime. The most distinguishable microstructural evolution by increasing the ECAP strain from similar to4 to similar to8 was an increment of a portion of high angle boundaries while the (sub)grain size remained almost unchanged. The sample after 4 passes (a strain of similar to4) did not exhibit LTS, but superplastic elongations were obtained in the sample after 8 passes (a strain of similar to8). An analysis of the mechanical data in light of the standard deformation mechanisms revealed that deformation of the sample after 4 passes was governed by dislocation climb while grain boundary sliding attributed to LTS of the sample after 8 passes. The difference of the deformation mechanisms in the present case was discussed in terms of the microstructures developed under different ECAP strains. [106] CRYSTALLOGRAPHIC ANISOTROPY CONTROL OF N-TYPE BI-TE-SE THERMOELECTRIC MATERIALS VIA BULK MECHANICAL ALLOYING AND SHEAR EXTRUSION Kim-SS; Aizawa-T - MATERIALS-TRANSACTIONS. MAR 2004; 45 (3) : 918-924. The shear extrusion processing combined with bulk mechanical alloying is proposed to yield the n-type Bi-Te-Se material from elemental granules. It has well-developed texture so as to improve the electric conductivity and thermoelectric properties. The shear extrusion processing of (Bi2Se3)(0.05)(Bi2Te3)(0.95) alloy green compact can afford the preferred orientation factor of anisotropic crystallographic structure: F = 0.67. The electric resistivity of (Bi2Se3)(0.05)(Bi2Te3)(0.95) is controlled to be 0.491 x 10(-5) (Omegam), which is 0.2 times lower than that of hot-pressed specimen. Maximum power factor is achieved to be 3.31 x 10(-3) (W/mK(2)) even without any dopants. The bending strength of the material produced in this work is also improved to be 166 MPa, 1.7 times higher than that of conventional hot-extruded specimens. [105] PRODUCTION OF AL2O3-TI3AL CERMETS BY THE PRESSURELESS REACTION SINTERING PROCESS Enrique, RR; Cesareo, EL; Guillermina, GM,n Editors: Bansal, NP; Singh, JP; Kriven, WM; Schneider, H - ADVANCES IN CERAMIC MATRIX COMPOSITES IX 81-87, 2003 - Book Series Title - CERAMIC TRANSACTIONS, 153, International Symposium on Recent Advances in Ceramic Matrix Composites - Nashville, TN, APR 27-30, 2003 , NASA Glenn Res Ctr, Engn Ceram Div, Amer Ceram Soc Dense Al2O3-aluminum intermetallic cermets with interpenetrating networks have been fabricated by a pressureless reaction sintering process. Compacts of intensively *ball* *milled* TiO2 + Al2O3 + Al powder mixtures are heat treated in an inert atmosphere such that the vigorous exothermic reaction between TiO2 and Al takes place in a controlled manner essentially at temperatures below the melting point of Al. Dense and homogeneous microstructures were obtained with an Al2O3 matrix and a TixAly intermetallics reinforcement. The present paper discusses processing details for the obtention of the mentioned cermet. [104] FABRICATION OF AL-7WT%SI-0.4WT%MG/SIC NANOCOMPOSITE POWDERS AND BULK NANOCOMPOSITES BY HIGH ENERGY BALL MILLING AND POWDER METALLURGY Woo-KD; Zhang-DL - CURRENT-APPLIED-PHYSICS. APR 2004; 4 (2-4) : 175-178. By using high energy ball milling of a mixture of powders, SiC nanometer sized particle included Al-7wt%Si-0.4wt%Mg composite powder can be obtained. The effect of milling on the Al-Si eutectic reaction of the matrix was studied and it was found that the eutectic reaction occurred during milling. High energy ball milling increased the sintering rate of the composite powder due to increasing diffusion rate that was affected by defect density. Due to the finer microstructure and less pore, the hardness of the sintered composite produced by using the mechanically milled nanocomposite powder was significantly higher than that of the sintered composite produced by using the mixed powder. The nanometer and submicrometer sized SiC particles were found in the sintered composite. [103] EFFECT OF CARBON ON HYDROGEN DESORPTION AND ABSORPTION OF MECHANICALLY MILLED MGH2 Shang CX, Guo ZX - JOURNAL OF POWER SOURCES - 129 (1): 73-80, APR 15 2004 - Conference on High Energy Density Electrochemical Power Sources - Nice, FRANCE, SEP 17-20, 2003 The use of MgH2, instead of pure Mg, in the mechanical synthesis of Mg-based hydrogen storage materials offers added benefit to powder size refinement and reduced oxygen contamination. Alloying additions can further improve the sorption kinetics at a relatively low temperature. This paper examines the effect of graphitic carbon on the desorption and absorption of MgH2. Graphite powder of different concentrations were mechanically milled with MgH2 particles. The milled powder was characterised by XRD, SEM and simultaneous TG and DSC techniques. The results show that graphite poses little influence on the desorption properties of MgH2. However, it does benefit the absorption process, leading to rapid hydrogen uptake in the re-hydrogenated sample. After dehydrogenation, 5 wt.% of hydrogen was re-absorbed within 30 min at 250degreesC for the (MgH2 + 10 G) mixture prior-milled for 8 h, while only 0.8 wt.% for the pure MgH2 milled for 8 h, the effect may be attributed to the interaction between crystalline graphite with H, disassociation close to the MgH, or Mg Surface. Moreover, graphite can also inhibit the formation of a new oxide layer on the surface of Mg particles [102] SYNTHESIS AND NOVEL APPLICATION OF NANOMATERIALS IN TUNGSTATE, TITANIA AND SILICON NITRIDE SYSTEMS Balazsi C - NANOSTRUCTURES: SYNTHESIS, FUNCTIONAL PROPERTIES AND APPLICATIONS - Editors: Tsakalakos T, Ovidko IA, Vasudevan AK - NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND

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CHEMISTRY, 128 - 655-673, 2003 - Conference of the NATO-Advanced-Study-Institute on Synthesis, Functional Properties and Applications of Nanostructures - Heraklion, GREECE, JUN 29-JUL 09, 2001 - NATO Adv Study Inst This paper summarizes some recent advances made in synthesis and application of nanomaterials in tungstate, titania and silicon nitride systems. Firstly, the room temperature acidic precipitation and ageing process of tungsten oxide dihydrate grains are presented. Fourier transform infrared spectroscopy studies have shown that structural stability of Freedman type grains can be altered by presence of Li+ and NH4+ ions. Water molecules and OH- groups present in structure play an important role in ion insertion process during ageing. As regards titania system a mechanochemical coating process is highlighted. Afterwards, a study about silicon nitride ceramics with well known properties as low density, high strength and toughness is presented. As an alternative way to improve the mechanical and thermal properties of silicon nitride matrix, we performed the preparation and examination of nano-crystalline carbon added silicon nitride. ceramic matrix composites. [101] PARTICULARITIES OF MARTENSITIC TRANSFORMATIONS IN NANOSRUCTURED FE-MN SYSTEM OBTAINED BY MECHANICAL ALLOYING Pustov LY, Kaloshkin SD, Estrin EI, Principi G, Tcherdyntsev VV, Shelekhov EV - NANOSTRUCTURES: SYNTHESIS, FUNCTIONAL PROPERTIES AND APPLICATIONS - Editors: Tsakalakos T, Ovidko IA, Vasudevan AK NATO SCIENCE SERIES, SERIES II: MATHEMATICS, PHYSICS AND CHEMISTRY, 128 - 329-337, 2003 - Conference of the NATO-Advanced-Study-Institute on Synthesis, Functional Properties and Applications of Nanostructures - Heraklion, GREECE, JUN 29-JUL 09, 2001 - NATO Adv Study Inst [100] PHASE TRANSITION OF MAGNETITE BY MECHANICAL ALLOYING Dutta-S; Manik-SK; Pal-M; Pradhan-SK; Brahma-P; - INDIAN-JOURNAL-OF-PHYSICS-AND-PROCEEDINGS-OF-THE-INDIAN-ASSOCIATION-FOR-THE-CULTIVATION-OF-SCIENCE-PART-A. MAR 2004; 78A (2) : 201-204. Nanocomposite of Fe3O4 (magnetite) and alpha-Fe2O3 have been prepared by mechanical grinding Fe3O4 powder at ambient with 20 : 1 ball to powder mass ratio (BPMR) for different durations. Crystalline phases and several microstructure parameters such as volume fraction of the individual phase, particle size, and strain have been determined by X-ray diffraction technique. A very interesting phase transformation kinetics has been noticed. With progress of milling volume fraction of Fe3O4 reduces and that of alpha-Fe2O3 increases. After 10 hr of milling, content of Fe3O4 phase reduces to as low as 0.05 volume fraction. After 6 hr of milling particle size of Fe3O4 phase reduces from 54 nm to 5 nm. Then the size of the particles increases to 10 nm and remains almost unchanged upto 10 hr milling. The growth of alpha-Fe2O3 phase has been initiated from the Fe3O4 phase with very small particle size (4 nm) and in course of milling duration particle size grows upto 11 nm after 6 hrs of milling in an unusual manner. DC electrical conductivity measurements were carried out in the temperature range 110-500 K. Resistivity of the nanocomposites exhibits semiconducting nature comprised of three different activation energies in an unusual manner. Conduction mechanism can be explained on the basis of microstructure induced in composites during milling [99] APPLICATION OF MECHANICAL ALLOYING AND SELF-PROPAGATING SYNTHESIS FOR PREPARATION OF STABLE DECAGONAL QUASICRYSTALS Bokhonov-B; Korchagin-A - JOURNAL-OF-ALLOYS-AND-COMPOUNDS. APR 14 2004; 368 (1-2) : 152-156. The X-ray and electron microscopic investigations demonstrated principal possibility to use self-propagation high-temperature synthesis (SHS) in combination with preliminary mechanical activation for the synthesis of stable decagonal quasicrystals. The decagonal quasicrystals formed in SHS process look like faceted decaprisms with a length of 300-400 mum and a thickness of 30-40 mum. SAD patterns are characterized by the presence of the axes of 10- and 2-fold symmetry. [98] MECHANOSYNTHESIS AND MECHANICAL ACTIVATION PROCESSES TO THE PREPARATION OF THE SR-2[S(N-1)TI(N)O3(N+1)] RUDDLESDEN-POPPER FAMILY Hungria-T; Hungria-AB; Castro-A - JOURNAL-OF-SOLID-STATE-CHEMISTRY. APR-MAY 2004; 177 (4-5) : 1559-1566 A novel mechanochemical activation route has been applied in order to obtain the n = 1-4 and infinity members of the Sr-2[Sr(n-1)TinO(3n+1)] Ruddlesden-Popper series. The evolution of the (n + 1)SrO:nTiO(2) powder mixtures during mechanical treatment was followed by X-ray powder diffraction in all cases. Except for the 2SrO:TiO2 composition, SrTiO3 was always mechanosynthesized. High-energy nailling of 2SrO:TiO2 sample resulted in the formation of nanosizcd Sr2TiO4, which is the only K2NiF4-type oxide prepared by mechanical treatment until now. The mechanical treatment was followed by annealing at different temperatures to establish the optimized protocol for synthesis of each member of the series. SrTiO3, Sr2TiO4 and Sr3Ti2O7 were obtained with very important decreases in the formation temperatures and reaction times as compared with the traditional ceramic method. Final and milled products were Studied by X-ray powder diffraction at room and increasing temperatures, and by thermal analysis and scanning and high resolution transmission electron microscopy. [97] EFFICIENT MECHANOCHEMICAL SYNTHESIS OF TRIS(PYRAZOLYLBORATE) COMPLEXES OF MANGANESE(II), COBALT(II) AND NICKEL(II) Kolotilov-SV; Addison-AW; Trofimenko-S; Dougherty-W; Pavlishchuk-VV - INORGANIC-CHEMISTRY-COMMUNICATIONS. APR 2004; 7 (4) : 485-488. A mechanochemical synthesis of Mn(II), Co(II) and Ni(II) tris(pyrazolylborates) (Tp(-)) was developed, which enabled preparation of metal complexes of the type TpMCl and TpMCl.Hpz type (Hpz is the substituted pyrazole generated by

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hydrolysis of the correspondin g Tp(-) ligand). The X-ray structure of a new Co(II) tris(pyrazolylborate) and the electronic spectra of these coordination compounds are discussed. [96] THE SYNTHESIS MECHANISM OF CA3AL2O6 FROM SOFT MECHANOCHEMICALLY ACTIVATED PRECURSORS STUDIED BY TIME-RESOLVED NEUTRON DIFFRACTION UP TO 1000 DEGREES C Mercury-JMR; De-Aza-AH; Turrillas-X; Pena-P - JOURNAL-OF-SOLID-STATE-CHEMISTRY. MAR 2004; 177 (3) : 866-874. The reaction pathway for the Ca3Al2O6 formation up to 1300degreesC, from mechanochemically treated mixtures of amorphous aluminum hydroxide and CaCO3, was studied in situ by differential thermal analysis, constant heating rate dilatometry and time-resolved neutron powder diffraction. The experiment was carried out, in an open system, on a sample with the nominal Ca3Al2O6 stoichiometry. The results obtained by neutron diffractometry and thermal analysis were in good agreement with the data obtained by scanning electron microscopy and X-ray diffraction on heat-treated and-quenched samples. The synthesis path implied the formation of cryptocrystalline Al2O3, crystalline CaO, CaAl2O4 and Ca12Al14O33 as transitory phases. Finally the nucleation and growth of the single phase Ca3Al2O6 took place at 1300degreesC and exhibited porous structure due to CO2 and H2O release. [95] MECHANOCHEMICAL-HYDROTHERMAL SYNTHESIS OF CALCIUM PHOSPHATE POWDERS WITH COUPLED MAGNESIUM AND CARBONATE SUBSTITUTION Suchanek-WL; Byrappa-K; Shuk-P; Riman-RE; Janas-VF; TenHuisen-KS - JOURNAL-OF-SOLID-STATE-CHEMISTRY. MAR 2004; 177 (3) : 793-799. Magnesium- and carbonate-substituted calcium phosphate powders (Mg-, CO3-CaP) with various crystallinity levels were prepared at room temperature via a heterogeneous reaction between MgCO3/Ca(OH)(2) powders and an (NH4)(2)HPO4 Solution using the mechanochemical-hydrothermal route. X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis were performed. It was determined that the powders containing both Mg2+ and CO32- ions were incorporated uniformly into all amorphous calcium phosphate phase while in contrast, the as-prepared powder free of these dopants was crystalline phase-pure, stoichiometric hydroxyapatitc. Dynamic light scattering revealed that the average particle size of the room temperature Mg-, CO3-CaP powders was in the range of 482 nm-700 nm nm with a specific surface area between 53 and 91 m(2)/g. Scanning clectron microscopy confirmed that the Mg-, CO3-CaP powders consisted of agglomerates of equiaxed, 20-35 nm crystals. [94] CATALYTIC PROPERTIES OF MECHANICALLY ACTIVATED HUMIC SUBSTANCES IN ELECTROREDUCTION OF OXYGEN Yudina-NV; Savel'-eva-AV; Ivanov-AA; Korotkova-EI; Lomovskii-OI - RUSSIAN-JOURNAL-OF-APPLIED-CHEMISTRY. JAN 2004; 77 (1) : 46-50. Effect of mechanical treatment of peat on the yield of the major fractions (polysaccharides, polyphenols, water-soluble compounds, and humic acids) and catalytic activity of humic substances in oxidation processes is studied. Conditions of formation of substances with the maximal antioxidant and initiating activities are determined. The antioxidant and initiating activities of the polysaccharide and humic fractions is studied, in relation to the structure and iron content. [93] A STUDY OF THE EFFECT OF ALUMINIUM ON THE MECHANOCHEMICAL REDUCTION OF HEMATITE BY GRAPHITE Khaki-JV; Panjehpour-M; Kashiwaya-Y; Ishii-K; Bafghi-MSS - STEEL-RESEARCH-INTERNATIONAL. MAR 2004; 75 (3) : 169-177 The effect of addition of small amounts of aluminium on mechano-chemical reduction of hematite by graphite was studied. Various amounts of aluminium (0 to 10%) were added to a hematite-graphite mixture, in which C/O ratio was 1:1. The hematite-graphite-aluminium mixtures were then subjected to ball milling followed by heating up reduction. The heating up reduction was carried out in Ar atmosphere, using TG-DTA device. In TG-DTA experiments, samples were heated by a constant heating rate of 10 degreesC/min from room temperature up to 1100 degreesC and maintained for 30 minutes at this temperature. To clarify the reactions which took place during milling and heating up reduction, the samples were subjected to XRD examinations. It was found that the heat generated during exothermic reaction of aluminothermic reduction of hematite promoted the endothermic reaction of carbothermic reduction. In the course of heating up reduction, the carbothermic reaction occurred just after aluminothermic reaction. Increasing of aluminum content from 0 to 10% in 2 hours ball milled samples decreased the temperature of carbothermic reaction from 1020 degreesC to about 860 degreesC. The further ball milling of the samples up to 5 and 10 hours, for the samples containing 10 and 5% aluminium respectively, caused the decrease of the temperature of aluminothermic and carbothermic reactions to around the melting point of aluminium. [92] ON THE BEHAVIOUR OF HEMATITE AND GRAPHITE BLEND DURING BALL MILLING AND HEATING UP REDUCTION OF MILLED MIXTURE Raygan-S; Khaki-JV; Aboutalebi-MR - STEEL-RESEARCH-INTERNATIONAL. MAR 2004; 75 (3) : 163-168. The effect of ball milling under argon and air atmospheres on the reaction behaviour of the mixture of sintered hematite and graphite was investigated. Thermo-gravimetry / differential thermal analysis (TG-DTA) was adopted to determine the effect of milling time on the reduction process during heating up under Ar atmosphere. The samples were heated at a constant

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heating rate of 10 degreesC/min from room temperature up to 1100 degreesC and maintained at this temperature for 30 minutes. TGL (thermo-gravimetry loss) curves showed a decrease of onset temperature of reduction with increase of milling time. XRD patterns of milled samples at room temperature revealed that the peaks of graphite disappeared after 48 hours milling. This represents the transformation of crystalline structure of graphite to the amorphous structure. By increasing the milling time to 72 hours, magnetite peaks appeared in the XRD pattern as a result of reduction of hematite with graphite during milling. However, the amount of magnetite formed during milling process increased as milling proceeded. The powders milled under Ar atmosphere became more active than the powders milled under air and consequently the carbothermic reduction of hematite in powders milled under Ar atmosphere was observed at lower temperatures compared with air-milled powders. It was observed that the reduction time of hematite in powder mixture was decreased with increase of sintering time of hematite prior to milling. [91] SYNTHESIS OF THE AURIVILLIUS PHASE SRBI4TI4O15 BY A MECHANOCHEMICAL ACTIVATION ROUTE Ferrer-P; Iglesias-JE; Castro-A - CHEMISTRY-OF-MATERIALS. APR 6 2004; 16 (7) : 1323-1329. This work reports the results obtained on the synthesis of the Aurivillius oxide SrBi4T4O15 as carried out by mechanochemically assisted methods. The effects of changing the milling media (vibrating and planetary mills) and the length of the mechanical treatment are discussed. The products obtained were characterized by X-ray diffraction at room and high temperatures, thermal analysis, and scanning electron microscopy. When an amorphous mechanochemically activated precursor is annealed at low temperatures, a novel Sr-Bi-Ti-O fluorite-related phase is isolated. The bismuth layered perovskite can be obtained with a significant decrease in temperature (of about 500 degreesC) and reaction time (several days), as compared with the conventional ceramic synthesis method. The mechanically treated samples exhibit a homogeneous particle size of around 300 nm, which increases with further thermal annealing. [90] NANOSTRUCTURED (COXFE1-X)(3-Y)O-4 SPINEL - MECHANOCHEMICAL SYNTHESIS Wu-E; Campbell-SJ; Kaczmarek-WA; Hofmann-M; Kennedy-SJ - ZEITSCHRIFT-FUR-METALLKUNDE. OCT 2003; 94 (10) : 1127-1133. The effects of wet-milling mixtures of alpha-Fe2O3 and cobalt hydroxide Co(OH)(2) over a range of Co/Fe ratios for 215 h have been investigated by neutron diffraction and Mossbauer spectroscopy. The starting materials were mixed according to the stoichiometric formula (CoxFe1-x)(3)O-4 for values of x = 0.037, 0.071, 0.133, 0.234 and 0.380 (i.e., from approximate to Co0.1Fe2.9O4 to the cobalt spinel CoFe2O4). These studies reveal the formation of a nanostructured, mixed Co-Fe spinel phase with non-stoichiometric composition (CoxFe1-x)(3-y)O-4; the defect spinels have refined values x(c) = 0.04, 0.08 and 0.14 for the mixtures with the lowest Co content (x = 0.037, 0.071 and 0.133) and defect concentrations in the range y approximate to 0.1 - 0.2. Both the spinel phase and un-reacted alpha-Fe2O3 are found to occur in the neutron diffraction patterns and Mossbauer spectra for the high Co content mixtures x = 0.234 and x = 0.380. Rietveld refinements of the neutron data indicate that the Co atoms predominantly occupy the octahedral B sites with vacancies also found to be located on the octahedral B sites. Analyses of the Mossbauer spectra of the milled samples confirm the existence of vacancy defects in the B sites and reveal that the vacancies cause similar effects to those of the Co ions, leading to a higher average charge state per iron atom [89] HYDRIDING/DEHYDRIDING PROPERTIES OF LA2MG16NI ALLOY PREPARED BY MECHANICAL BALL MILLING IN BENZENE AND UNDER ARGON Chi-HZ; Chen-CP; Chen-LX; An-Y; Wang-QD - INTERNATIONAL-JOURNAL-OF-HYDROGEN-ENERGY. JUL 2004; 29 (7) : 737-741. The hydrogen storage properties of La2Mg16Ni alloy prepared by mechanical milling in benzene or under argon were investigated. The scanning electron microscope results show that there are obvious differences in the surface morphology for different ball milling conditions. Compared with the sample milled under argon, the alloy milled in benzene has relatively faster absorption/desorption kinetics. Furthermore, the milling in benzene destabilizes the alloy hydride. The ball milling in organic solvent offers a new way for magnesium-based hydrogen storage materials, exploiting their higher capacity and higher equilibrium pressure while operating at lower temperature. [88] SYNTHESIS AND CHARACTERIZATIONS OF NANOCRYSTALLINE WC-CO COMPOSITE POWDERS BY A UNIQUE BALL MILLING PROCESS Shen-J; Sun-JF; Zhang-FM - JOURNAL-OF-MATERIALS-SCIENCE-AND-TECHNOLOGY. JAN 2004; 20 (1) : 7-10. In order to explore the high efficiency of fabricating nanocrystalline WC-Co composite powders, this paper presented, a unique high energy ball milling process with variable rotation rate and repeatious circulation, by which nanocrystalline WC-10Co-0.8VC-0.2Cr(3)C(2) (wt pct) composite powders with mean grain size of 25 nm were prepared in 32 min, and the quantity of the powders for a batch was as much as 800 grams. The as-prepared powders were analyzed and characterized by chemical analysis, X-ray diffraction (XRD), transmission electron microscopy (TEM) and differential thermal analysis (DTA). The results show that high energy ball milling with variable rotation rates and repeatious circulation could be used to produce nanocrystalline WC-Co powder composites with high efficiency. The compositions of the powders, meet its specifications with low impurity content. The mean grain size decreases, lattice distortion and system energy increase with increasing the milling time. The morphology of nanocrystalline WC-Co particles displays dominantly sphere shape and their particle sizes are all lower than 80 nm. The eutectic temperature of the nanocrystalline WC-10Co-0.8VC-0.2Cr(3)C(2)

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composites is about 1280degreesC [87] NEURAL NETWORK MODELING AND CONTROL OF CEMENT MILLS USING A VARIABLE STRUCTURE SYSTEMS THEORY BASED ON-LINE LEARNING MECHANISM Topalov-AV; Kaynak-O - JOURNAL-OF-PROCESS-CONTROL. AUG 2004; 14 (5) : 581-589. It is well known that the major cause of instability in industrial cement ball mills is the so-called plugging phenomenon. A novel neural network adaptive control scheme for cement milling circuits that is able to fully prevent the mill from plugging is presented. Estimates of the one-step-ahead errors in control signals are calculated through a neural predictive model and used for controller tuning. A robust on-line learning algorithm, based on sliding mode control (SMC) theory is applied to both: to the controller and to the model as well. The proposed approach allows handling of mismatches, uncertainties and parameter changes in the model of the mill. The simulation results from indicate that both the neural model and the controller inherit the major advantages of SMC, i.e. robustness. Furthermore, learning is achieved in a rapid manner [86] COLLAGEN PROCESSING Maffia-GJ; Selter-MA; Cooke-PH; Brown-EM - JOURNAL-OF-THE-AMERICAN-LEATHER-CHEMISTS-ASSOCIATION. APR 2004; 99 (4) : 164-169. Collagen dispersions, produced from fibrils recovered from milled bovine collagen, have shown promise in environmental remediation in applications as settling aids, filtration aids, fractionation media, oil drop stabilizers, and water purification aids. Macroporous structures, processed by controlled lyophilization of collagen dispersions, are suitable as cell culturing substrates. Collagen was structurally characterized during milling to assist in designing a method for scale-up of the production process. In fact, although the initial processing involves a ball mill, the actual operation is more of an unraveling of the fiber to expose the fibrils, which have nanoscale dimensions. During the ball-milling step of production the active surface area of the collagen increases more than 200 times without chemically altering or denaturing the collagen. To demonstrate this throughout the milling process, active surface area per mass, fibril structure, molecular weight distribution, percent lipid, percent nitrogen, and percent ash were monitored. [85] MAGNETIC PROPERTIES OF MECHANICALLY ALLOYED AND ANNEALED POWDERS FE-100-XCX (X=5 AND 15 AT.%) Ul'-yanov-AI; Elsukov-EP; Zagainov-AV; Arsent'-eva-NB; Dorofeev-GA; Fomin-VM - RUSSIAN-JOURNAL-OF-NONDESTRUCTIVE-TESTING. SEP 2003; 39 (9) : 683-696. The effect of the structural state and the phase composition on the magnetic hysteresis properties of Fe(95)C(5) and Fe(85)C(15) powders after mechanical alloying and annealing is investigated. It is shown that in the initial stage of grinding in a ball planetary mill the coercive force of the Fe-C powders is determined by the degree of defectiveness of the alpha-Fe phase and the relative volume and dimensions of nonmagnetic graphitic inclusions in iron powder particles. As the grinding time increases, the alpha-Fe phase goes over into a nanostructure state and carbon from graphite inclusions goes over into an amorphous Am(Fe-C) phase. After annealing on the temperature interval 300-600degreesC, the amorphous Am(Fe-C) phase is transformed into Fe3C ferric carbide. The coercive force of the Fe3C phase strongly depends on the degree of distortion of its crystal lattice and amounts to similar to 80 A/cm for the phase with distorted lattice and similar to 240 A/cm for the phase with equilibrium undistorted lattice. The magnetic characteristics of the powder after mechanical alloying and subsequent annealing are determined by the type, amount, and structural state of the phases containing in the samples. [84] HYDROGEN STORAGE IN PROTON-CONDUCTIVE PEROVSKITE-TYPE OXIDES AND THEIR APPLICATION TO NICKEL-HYDROGEN BATTERIES Esaka-T; Sakaguchi-H; Kobayashi-S - SOLID-STATE-IONICS. JAN 2004; 166 (3-4) : 351-357. In order to obtain a new anode material of hydrogen battery, perovskite-type oxide powders were prepared by a conventional solid-state reaction method and a subsequent mechanical milling using a planetary ball-milling machine. Hydrogen charge and discharge properties were investigated electrochemically in a three-electrode cell with KOH solution. As a result, the sample shown by ACe(1-x)M(x)O(3-delta) (A = Sr or Ba, M = rare earth element) was found to store hydrogen in the bulk and repeat hydrogen charge and discharge at room temperature, which suggested that the oxides are candidates for anode materials of hydrogen batteries. The maximum content of hydrogen stored was 119 mA It g(-1) for BaCe0.95N0.05O3-delta, which corresponded to the fact that 1.44 hydrogen atoms were present in one formula of the sample. However, the cycleability was degraded with increasing the cycle number. Considering higher hydrogen-storage performance in the cerium-containing perovskite-type oxides than in the others, the valence change in cerium would have an important role to store hydrogen. Furthermore, the fact that the 1.44 hydrogens stored exceed the number of cerium in the formula Suggested the presence of atomic hydrogen in the perovskite-type oxide like in the hydrogen storage alloys. [83] A STUDY OF THE EFFECT OF ALUMINIUM ON THE MECHANOCHEMICAL REDUCTION OF HEMATITE BY GRAPHITE Khaki-JV; Panjehpour-M; Kashiwaya-Y; Ishii-K; Bafghi-MSS - STEEL-RESEARCH-INTERNATIONAL. MAR 2004; 75 (3) : 169-177. The effect of addition of small amounts of aluminium on mechano-chemical reduction of hematite by graphite was studied. Various amounts of aluminium (0 to 10%) were added to a hematite-graphite mixture, in which C/O ratio was 1:1. The hematite-graphite-aluminium mixtures were then subjected to ball milling followed by heating up reduction. The heating up

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reduction was carried out in Ar atmosphere, using TG-DTA device. In TG-DTA experiments, samples were heated by a constant heating rate of 10 degreesC/min from room temperature up to 1100 degreesC and maintained for 30 minutes at this temperature. To clarify the reactions which took place during milling and heating up reduction, the samples were subjected to XRD examinations. It was found that the heat generated during exothermic reaction of aluminothermic reduction of hematite promoted the endothermic reaction of carbothermic reduction. In the course of heating up reduction, the carbothermic reaction occurred just after aluminothermic reaction. Increasing of aluminum content from 0 to 10% in 2 hours ball milled samples decreased the temperature of carbothermic reaction from 1020 degreesC to about 860 degreesC. The further ball milling of the samples up to 5 and 10 hours, for the samples containing 10 and 5% aluminium respectively, caused the decrease of the temperature of aluminothermic and carbothermic reactions to around the melting point of aluminium. [82] ON THE BEHAVIOUR OF HEMATITE AND GRAPHITE BLEND DURING BALL MILLING AND HEATING UP REDUCTION OF MILLED MIXTURE Raygan-S; Khaki-JV; Aboutalebi-MR - STEEL-RESEARCH-INTERNATIONAL. MAR 2004; 75 (3) : 163-168. The effect of ball milling under argon and air atmospheres on the reaction behaviour of the mixture of sintered hematite and graphite was investigated. Thermo-gravimetry / differential thermal analysis (TG-DTA) was adopted to determine the effect of milling time on the reduction process during heating up under Ar atmosphere. The samples were heated at a constant heating rate of 10 degreesC/min from room temperature up to 1100 degreesC and maintained at this temperature for 30 minutes. TGL (thermo-gravimetry loss) curves showed a decrease of onset temperature of reduction with increase of milling time. XRD patterns of milled samples at room temperature revealed that the peaks of graphite disappeared after 48 hours milling. This represents the transformation of crystalline structure of graphite to the amorphous structure. By increasing the milling time to 72 hours, magnetite peaks appeared in the XRD pattern as a result of reduction of hematite with graphite during milling. However, the amount of magnetite formed during milling process increased as milling proceeded. The powders milled under Ar atmosphere became more active than the powders milled under air and consequently the carbothermic reduction of hematite in powders milled under Ar atmosphere was observed at lower temperatures compared with air-milled powders. It was observed that the reduction time of hematite in powder mixture was decreased with increase of sintering time of hematite prior to milling. [81] A SIMPLE ROLLER-MILL GRINDING PROCEDURE FOR PLANT AND SOIL SAMPLES Arnold-SL; Schepers-JS - COMMUNICATIONS-IN-SOIL-SCIENCE-AND-PLANT-ANALYSIS. FEB 2004; 35 (3-4) : 537-545. Obtaining finely ground, homogeneous plant and soil samples for chemical analysis without cross contamination is a major concern when using direct combustion procedures for determination of total nitrogen (N), total carbon (C), and isotope-ratio analysis. A rollermilling device, using square glass bottles instead of round grinding bottles, was evaluated. Rotation of the square bottles on the roller mechanism increased the milling action by the stainless steel rods inside the bottles. The roller-milling device with square grinding bottles resulted in a sample with smaller particles (99.2% <100 mesh) than with a ball-milling device (83% <100 mesh). The roller-mill provided acceptable results (soil and plant samples ranging from 1.6-43.8% C, 0.5-2.3% N, and 0.3777-1.038 atom% N-15 (isotopic ratio analysis) had coefficients of variation ranging from 0.44-1.78, to 0.97-1.60, and 0.09-1.43, respectively) while providing an economical approach to grinding large numbers of samples to achieve finely ground, homogeneous samples with minimal labor and equipment costs. [80] EFFECT OF BALL MILLING ON THE CORROSION RESISTANCE OF MAGNESIUM IN AQUEOUS MEDIA Grosjean-MH; Zidoune-M; Roue-L; Huot-J; Schulz-R - ELECTROCHIMICA-ACTA. JUN 30 2004; 49 (15) : 2461-2470. The influence of the high-energy ball milling on the corrosion behavior of magnesium in aqueous media has been investigated through electrochemical experiments complemented by morphological, structural, chemical and surface analyses. The milling duration was varied from 0 to 40 It. Polarization curves show that the milling procedure improves the magnesium corrosion resistance in passive conditions (KOH solution) and in more active corrosion conditions (borate solution). This is illustrated by the corrosion potential which becomes nobler with milling. The variation of the polarization resistance and related corrosion current with milling time is also an indication of the improvement of the Mg corrosion resistance due to the milling. Moreover, the passive current is significantly lower for milled Mg. The Mg crystallite size is reduced from >100 to 34 nm after 10 h of milling and does not decrease significantly with further milling. The iron contamination of the Mg powder due to the erosion of the milling tools is very low (0.09 wt.% after 40 h of milling). In contrast, a significant oxygen contamination occurs during milling (2.6 wt.% after 40 h of milling). XPS and AES data indicate MgO enrichment in the bulk of the milled Mg without significant MgO increase at the powder surface. The corrosion improvement was attributed to the increase through the milling process of the density of surface defects and grain boundaries susceptible to increase the number of nucleation sites for Mg hydroxylation in aqueous media, leading to the rapid formation of a dense and protective Mg(OH)(2) layer. [79] A NOVEL METHOD FOR THE DETERMINATION OF GRAIN SIZE DISTRIBUTION AND MICROSTRAIN IN NANOCRYSTALLINE MATERIALS FROM SINGLE X-RAY DIFFRACTION PEAK Chatterjee-P; Deb-AK; Sen-Gupta-SP - INDIAN-JOURNAL-OF-PHYSICS-AND-PROCEEDINGS-OF-THE-INDIAN-

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ASSOCIATION-FOR-THE-CULTIVATION-OF-SCIENCE-PART-A. MAR 2004; 78A (2) : 205-209. A new method for determining simultaneous grain-size distribution and microstrain from single X-ray diffraction peak is presented. The method combines both the single peak real-space method of Langford and single peak fourier-space method of Nandi et al to determine two apparent size parameters. If the morphology of the grains is known from a separate experiment (viz. TEM) the apparent size value may be used to determine the grain size distribution. In the present work a log-normal distribution of spherical grains was assumed and the median and variance of the distribution was determined for ball-milled vanadium-pentoxide samples. It is proposed that the present method givcs reliable information regarding grain size distribution and microstrain compared to any other single peak methods. The method may be widely applicable to most nanocrystalline materials with only limitation in case of materials exhibiting grain size disparity (viz. bi-modal or multi-modal size distribution) and does not require extensive TEM analysis. [78] MECHANOCHEMICAL ROUTE FOR THE SYNTHESIS OF COBALT FERRITE-SILICA AND IRON-COBALT ALLOY-SILICA NANOCOMPOSITES Ennas-G; Marongiu-G; Marras-S; Piccaluga-G - JOURNAL-OF-NANOPARTICLE-RESEARCH. FEB 2004; 6 (1) : 99-105. CoFe2O4-SiO2 and Fe - Co alloy - SiO2 nanocomposites were prepared by high energy ball milling of Si, alpha-Fe2O3, Co3O4 and SiO2 mixtures, followed by thermal treatment under appropriate oxidative/reductive conditions. XRD and TEM measurements carried out after 50 h of milling show highly dispersed unidentified reaction products. Further thermal treatment at 900degreesC in air leads to spherical CoFe2O4 nanocrystals (NCs) with a narrow size distribution centered around 2.5 nm, uniformly dispersed in the amorphous SiO2 matrix. Reduction of this sample in a H-2 flow at 800degreesC produces a mixture of dispersed metallic cobalt and iron silicate with traces of Fe - Co alloy NCs. Reduction of the as-milled sample, on the contrary, leads almost completely to Fe - Co alloy NCs uniformly dispersed in the SiO2 matrix and with an average particles size around 11.2 nm. [77] THE LAMOX FAMILY OF FAST OXIDE-ION CONDUCTORS: OVERVIEW AND RECENT RESULTS Georges-S; Goutenoire-F; Bohnke-O; Steil-MC; Skinner-SJ; Wiemhofer-HD; Lacorre-P - JOURNAL-OF-NEW-MATERIALS-FOR-ELECTROCHEMICAL-SYSTEMS. JAN 2004; 7 (1) : 51-57. A short review of our recent works and original results on the new LAMOX family of fast oxide-ion conductors based on La2Mo2O9 are presented. The order/disorder phase transition of La2Mo2O9, accompanied by an increase of anion conductivity, is suppressed by most of the substituants which stabilize the highly conducting cubic phase down to room temperature. The series La2-xRxMo2-yWyO9 (R=Nd, Gd, Y) was studied with respect to the optimisation of anion conduction and stability against reduction. Tungsten substitution is a good way to minimize oxygen loss under reducing atmosphere, a drawback in applications such as electrolytes for solid oxide fuel cells. Ball-milling and dilatometric studies allowed an efficient control and improvement of the samples relative density, for a better characterisation of the oxygen diffusion properties, a first account of which is presented here. The LAMOX family exhibits among the highest oxygen tracer diffusion coefficients. A specific curvature in the conductivity curves of cubic substituted phases is interpreted as resulting from a VTF-type conduction mechanism above a certain temperature, an indication of the existence of a dynamic disorder at high T, which would freeze while cooling down. [76] ENERGY-BASED ANALYSIS OF MILLING ALPHA-LACTOSE MONOHYDRATE Chen-Y; Ding-Y; Papadopoulos-DG; Ghadiri-M - JOURNAL-OF-PHARMACEUTICAL-SCIENCES. APR 2004; 93 (4) : 886-895. Some observations on the milling of a-lactose monohydrate with a Retsch single-ball mill are reported. The effects of mill loading and frequency of the mill motion were investigated. At a given frequency, a lower mill loading showed a higher milling efficiency. For a given mill loading, size reduction rate increased exponentially with frequency. The milling behavior was analyzed with three energy-based models; namely, Rittinger's, Kick's, and Bond's models. The results suggest that Rittinger's model best describes the milling behavior for low mill loadings at high frequencies, whereas the data for high loading milling at low frequencies fit Kick's model better. The results also indicate that attrition and/or chipping is the dominant mechanism for milling at low frequencies with high loadings because of the shear action of the milling ball rolling on the powder bed. Also, as a result of impact of the milling ball on the two ends of the milling jar, fragmentation is responsible for size reduction at high frequencies with low loadings. [75] SOLID STATE SYNTHESIS OF AL-BASED AMORPHOUS AND NANOCRYSTALLINE AL-NB-SI AND AL-ZR-SI ALLOYS Manna-I; Chattopadhyay-PP; Banhart-F; Fecht-HJ - ZEITSCHRIFT-FUR-METALLKUNDE. JUL 2003; 94 (7) : 835-841. This study concerns the development of high-specific-strength Al-based amorphous and/or nanocrystalline alloys by mechanical alloying of Al40TM40Si20 and Al30TM40Si30 (TM = transition metal, Nb and Zr) elemental powder blends by high-energy ball milling. Microstructure of the milled product in different stages of milling has been characterized by X-ray diffraction, high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. Both the systems are amenable to partial solid state amorphisation and development of a composite microstructure comprising varying amounts of nanocrystalline face-centred cubic Nb- or Zr-based solid solution and amorphous phase by appropriate hours of milling. The body-centred to face-centred cubic polymorphic change in Nb or Zr seems closely related to grain refinement and plastic strain.

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[74] OXIDE DISPERSION-STRENGTHENED SILVER: MANUFACTURING AND PROPERTIES Grundmann-U; Heilmaier-M; Martin-U; Oettel-H; Schultz-L - ZEITSCHRIFT-FUR-METALLKUNDE. MAY 2003; 94 (5) : 587-592. Novel oxide dispersion-strengthened (ODS) silver alloys were synthesised by mechanical alloying and subsequent consolidation via hot pressing in protective atmosphere. The effect of dispersoid size and volume fraction on the electrical and mechanical properties is exemplified with Cr2O3, CaO and Y2O3 as model candidates for a systematic study of the principles of particle selection. The results for the development of the microstructure under different processing conditions show that control of the impurity level is of primary importance for achieving high-quality, fully dense material. Hence, a modified cryo-milling technique at liquid-N-2 temperature was applied. Data at ambient temperature are presented, revealing that the mechanical and electrical proper-ties can be tailored within a wide range as a function of the microstructure. These results are explained by microstructural concepts for room temperature yielding and electrical conductivity. [73] X-RAY DIFFRACTION AND MOSSBAUER STUDIES OF NANOCRYSTALLINE FE-NI ALLOYS PREPARED BY MECHANICAL ALLOYING Djekoun-A; Bouzabata-B; Otmani-A; Greneche-JM - CATALYSIS-TODAY. MAR 30 2004; 89 (3) : 319-323. Mechanical alloying is a powder metallurgy processing technique involving cold welding, fracturing, and rewelding of powder particles in a high-energy ball mill. Mechanical alloying is a non-equilibrium process for materials synthesis. It has been used to obtain nanocrystalline binary Fe-Ni system. Elemental powders of iron and nickel (Fe-50 at.% Ni) have been mixed in a planetary mill. The structural effects of mechanical alloying of powders were investigated by scanning electron microscopy, X-ray diffraction analysis and Mossbauer spectroscopy. It is observed a gradual formation of mixture of phases as fcc (gamma) with a nanoscale grain size. In addition, as the average grain size is decreased with a progressive enlargement of peaks of X-ray diffraction, a paramagnetic phase appears after 48 h of ball milling detected by Mossbauer spectroscopy. [72] HYDRIDING/DEHYDRIDING PROPERTIES OF LA2MG16NI ALLOY PREPARED BY MECHANICAL BALL MILLING IN BENZENE AND UNDER ARGON Chi-HZ; Chen-CP; Chen-LX; An-Y; Wang-QD - INTERNATIONAL-JOURNAL-OF-HYDROGEN-ENERGY. JUL 2004; 29 (7) : 737-741. The hydrogen storage properties of La2Mg16Ni alloy prepared by mechanical milling in benzene or under argon were investigated. The scanning electron microscope results show that there are obvious differences in the surface morphology for different ball milling conditions. Compared with the sample milled under argon, the alloy milled in benzene has relatively faster absorption/desorption kinetics. Furthermore, the milling in benzene destabilizes the alloy hydride. The ball milling in organic solvent offers a new way for magnesium-based hydrogen storage materials, exploiting their higher capacity and higher equilibrium pressure while operating at lower temperature. [71] MECHANICAL SYNTHESIZED NANOCRYSTALLINE TI/AL COMPOSITE POWDERS AS PRECURSOR FOR TI/AL ALLOY VIA REACTIVE SINTERING Hu-LX; Li-XQ; Wang-E - JOURNAL-OF-ADVANCED-MATERIALS. APR 2004; 36 (2) : 30-34. TiAl alloy and powders with high purity and low oxygen contents were synthesized by ICS. Its densification was studied by both hot isostatic pressing (HIP) and conventional press-sintering process. The samples, with density of more than 3.75g/cm(3), were obtained by HIP at 196 MPa and 1250degrees C for 3h. The microstructure consisted of equiaxed grains and a small volume fraction of lamellar structure. The compressive tests showed the yield strength of TiAl sample was 646 MPa, the compressive strength was 1579 MPa and compressive ductility was above 26%. The addition of Mn and Cr changed the structure, and increased the volume of alpha(2) phase. The density of the powder compact sintered directly might reach the value of theoretical density. [70] NANOCRYSTALLINE AG-FE-SN ANODE MATERIALS FOR LI-ION BATTERIES Yin-JT; Wada-M; Tanase-S; Sakai-T - JOURNAL-OF-THE-ELECTROCHEMICAL-SOCIETY. 2004; 151 (4) : A583-A589. The Ag-Fe-Sn alloy powders prepared by mechanical alloying technique have been studied as anode material for lithium-ion batteries. The half-cell tests with lithium counter electrode revealed that a suitable substitution of Fe for Ag led to a significant improvement of the cycling performance of the electrodes. Among these electrodes, the Ag36.4Fe15.6Sn48 electrode was found to be capable of keeping a rechargeable capacity of about 280 mAh/g over 300 cycles, which was better than that of the Fe-free Ag52Sn48 electrode. Typically, the structural changes of the Ag26Fe26Sn48 electrode during Li insertion and/or extraction were characterized using the combined techniques involving X-ray diffraction, high resolution transmission electron microscopy, selected area electron diffraction, and energy dispersive X-ray spectrometry. It is considered that the electrochemical properties of these electrodes are associated with their microstructure and morphology, such as the distribution of intermetallic compound Ag3Sn in Sn matrix, the Ag3Sn/Sn ratio as well as the presence of inactive Fe. [69] MECHANISM OF LITHIUM INSERTION INTO MAGNESIUM SILICIDE Roberts-GA; Cairns-EJ; Reimer-JA - JOURNAL-OF-THE-ELECTROCHEMICAL-SOCIETY. 2004; 151 (4) : A493-A496.

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The reaction mechanism for electrochemical lithium insertion into magnesium silicide was studies by in situ and ex situ X-ray diffraction (XRD). Lithium intercalation during the initial stages of insertion was indicated by a slight shift toward lower angles in the diffraction patterns. Upon further insertion, Li2MgSi was formed. This was indicated by the appearance of magnesium peaks, the disappearance of Mg2Si peaks, and the appearance of Li2MgSi peaks in the diffraction patterns. Magnesium XRD peaks that accumulated during cycling indicated that the formation of Mg2Si during lithium removal was not entirely reversible. Li2MgSi was synthesized by mechanical alloying. XRD patterns and nuclear magnetic resonance spectra of the mechanically alloyed and electrochemically produced phases are compared [68] BULK GLASS FORMING AND THERMAL STABILITY IN FE67.0CO9.5ND3.0DY0.5B20 ALLOY Parida-S; Ram-S; Eckert-J; Roth-S; Loser-W; Schultz-L - MATERIALS-LETTERS. MAY 2004; 58 (12-13) : 1844-1852. Bulk glass forming ability (GFA) of a multicomponent alloy of Fe67.0Co9.5Nd3.0Dy0.5B20 is studied by synthesizing it in shapes of thin ribbons, rods or cylinders, or pellets. The three samples are obtained with three different methods of melt spinning, copper mold casting, or mechanical attrition (of ribbons) followed by a hot compaction of derived alloy powder, respectively. A melt-spun ribbon of 50- to 100-mum thickness has a truly amorphous structure with two X-ray diffraction halos of wavevectors q(1) = 14.2 and q(3) = 33.0 nm(-1). A modified diffractogram consists of two halos q(1) = 14.5 and q(2) = 19.0nm(-1) in the rods (3.0-mm diameter) while of three halos q(1) = 13.4,q(2) = 15.0andq(3) = 24.0 q(3) = 24.0 nm(-1) in the pellets (5- to 10-mm diameter and 3- to 5-mm thickness). A small value of coercivity H-c of 7.1 kA/m in the rods or almost zero in the ribbons reveals soft magnetic behaviors characteristic of an amorphous structure of the alloy. An improved value of H-c = 188.5 kA/m develops in the hot compressed pellets of the powder at similar to 630 degreesC temperature. The pellets have some recrystallized alpha-Fe, Fe3B and R2Fe14B (R=Nd or Dy) nanocrystallites in a bulk amorphous composite structure. The results are analyzed with thermal analysis and microstructures of the samples. [67] HYDROGEN STORAGE IN PROTON-CONDUCTIVE PEROVSKITE-TYPE OXIDES AND THEIR APPLICATION TO NICKEL-HYDROGEN BATTERIES Esaka-T; Sakaguchi-H; Kobayashi-S - SOLID-STATE-IONICS. JAN 2004; 166 (3-4) : 351-357. In order to obtain a new anode material of hydrogen battery, perovskite-type oxide powders were prepared by a conventional solid-state reaction method and a subsequent mechanical milling using a planetary ball-milling machine. Hydrogen charge and discharge properties were investigated electrochemically in a three-electrode cell with KOH solution. As a result, the sample shown by ACe(1-x)M(x)O(3-delta) (A = Sr or Ba, M = rare earth element) was found to store hydrogen in the bulk and repeat hydrogen charge and discharge at room temperature, which suggested that the oxides are candidates for anode materials of hydrogen batteries. The maximum content of hydrogen stored was 119 mA It g(-1) for BaCe0.95N0.05O3-delta, which corresponded to the fact that 1.44 hydrogen atoms were present in one formula of the sample. However, the cycleability was degraded with increasing the cycle number. Considering higher hydrogen-storage performance in the cerium-containing perovskite-type oxides than in the others, the valence change in cerium would have an important role to store hydrogen. Furthermore, the fact that the 1.44 hydrogens stored exceed the number of cerium in the formula Suggested the presence of atomic hydrogen in the perovskite-type oxide like in the hydrogen storage alloys. [66] STRUCTURE, SUPERCONDUCTIVITY AND MAGNETIC PROPERTIES OF MECHANICALLY ALLOYED MG1-XFEXB2 POWDERS WITH X=0-0.4 Gao-YD; Ding-J; Chen-Q; Rao-GVS; Chowdari-BVR - ACTA-MATERIALIA. APR 5 2004; 52 (6) : 1543-1553. Mechanical milling of Mg1-x FexB2 with x = 0-0.4 led to the formation of amorphous phase. For x = 0, the hexagonal MgB2 phase was formed after it heat treatment at 450 degreesC or above with critical temperature T-c = 38-40 K. Fe-substituted MgB2 phase was formed after annealing at 450 degreesC or above when x = 0.05. 0.1 and 0.2. Fe solubility in the MgB2 phase decreased with increasing annealing temperature, while lattice parameters (a and c) decreased. It has been found that critical temperature Tc increased with increasing annealing temperature. For Mg0.6Fe0.4B2 powder, MgB2 phase could not be formed after crystallization. Single solid-solution MgB2 phase could be formed in Mg0.95Fe0.05B2 after annealing at 450 degreesC. This sample exhibited paramagnetic between 30 and 290 K with a high magnetic moment of mu(Fe) = 5.5-6.0mu(B), An anomaly (minimum in reciprocal magnetic susceptibility) was observed below 30 K. accompanied by magnetic splitting in Mossbauer Spectroscopy. [65] DEVELOPMENT OF HARD MAGNETIC BULK AMORPHOUS ALLOYS Ram-S - CURRENT-SCIENCE. MAR 25 2004; 86 (6) : 832-838. Peculiarly, hard magnetic properties appear in a specific bulk amorphous structure in rare-earth (R) based R-Fe-Al (Ga) alloys and derivatives. A value of energy-product (JH)(max) of 10 to 25 kJ/m(3) occurs at room temperature. Different methods of rapid quenching, mechanical milling, arc melting, copper mold casting and water quenching are used to synthesize the alloys in amorphous structure. The hard properties no longer persist on recrystallizing the bulk alloy or on milling it into a fine powder. Thin melt-spun alloy ribbons (similar to0.1 min or smaller thickness) behave to be soft magnetic only. A similar alloy obtained in a powder form by elemental milling has soft magnetic properties. The results are compared to those in R2Fe14B and other R-based magnetic materials. In principle, a high value of (JH)(max) occurs in support of a high value of coercivity H-c and remanence J(r). A primary source of H-c is the magnetocrystalline anisotropy H-a but that does not exist in amorphous structure. In absence of Hag an amorphous material is not expected to give such a large value of H, as observed here in R-Fe-Al (Ga) alloys, with R = Nd, Pr, or Er. The values of H-c, J(r), Curie temperature

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T-C, as well as (JH)(max) are found to be optimal at an optimal Fe similar to 30 at% content. [64] COMPARISON AMONG THE LOCAL ATOMIC ORDER OF AMORPHOUS TM-TI ALLOYS (TM = CO, NI, CU) PRODUCED BY MECHANICAL ALLOYING STUDIED BY EXAFS Machado-KD; de-Lima-JC; Campos-CEM; Grandi-TA - EUROPEAN-PHYSICAL-JOURNAL-B. FEB 2004; 37 (4) : 421-424. We have investigated the local atomic structure of amorphous TM-Ti alloys (TM = Co, Ni, Cu) produced by Mechanical Alloying by means of EXAFS analyses on TM and Ti K-edges. Coordination numbers and interatomic distances for the three alloys where found and compared. EXAFS results obtained indicated a shortening in the unlike pairs TM-Ti as the difference between d electrons of TM and Ti atoms increases, suggesting an increase in the chemical short range order (CSRO) from TM = Co to Cu. [63] PHASE TRANSITION OF MAGNETITE BY MECHANICAL ALLOYING Dutta-S; Manik-SK; Pal-M; Pradhan-SK; Brahma-P; Chakravorty-D - National Seminar on Science and Technology of Nanomaterials JABALPUR, INDIA, MAR 06-07, 2003 - INDIAN-JOURNAL-OF-PHYSICS-AND-PROCEEDINGS-OF-THE-INDIAN-ASSOCIATION-FOR-THE-CULTIVATION-OF-SCIENCE-PART-A. MAR 2004; 78A (2) : 201-204. Nanocomposite of Fe3O4 (magnetite) and alpha-Fe2O3 have been prepared by mechanical grinding Fe3O4 powder at ambient with 20 : 1 ball to powder mass ratio (BPMR) for different durations. Crystalline phases and several microstructure parameters such as volume fraction of the individual phase, particle size, and strain have been determined by X-ray diffraction technique. A very interesting phase transformation kinetics has been noticed. With progress of milling volume fraction of Fe3O4 reduces and that of alpha-Fe2O3 increases. After 10 hr of milling, content of Fe3O4 phase reduces to as low as 0.05 volume fraction. After 6 hr of milling particle size of Fe3O4 phase reduces from 54 nm to 5 nm. Then the size of the particles increases to 10 nm and remains almost unchanged upto 10 hr milling. The growth of alpha-Fe2O3 phase has been initiated from the Fe3O4 phase with very small particle size (4 nm) and in course of milling duration particle size grows upto 11 nm after 6 hrs of milling in an unusual manner. DC electrical conductivity measurements were carried out in the temperature range 110-500 K. Resistivity of the nanocomposites exhibits semiconducting nature comprised of three different activation energies in an unusual manner. Conduction mechanism can be explained on the basis of microstructure induced in composites during milling [62] SYNTHESIS OF NANO-QUASIERYSTALLINE DECAGONAL PHASE Yadav-TP; Mukhopadhyay-NK; Srivastava-ON - National Seminar on Science and Technology of Nanomaterials JABALPUR, INDIA, MAR 06-07, 2003 - INDIAN-JOURNAL-OF-PHYSICS-AND-PROCEEDINGS-OF-THE-INDIAN-ASSOCIATION-FOR-THE-CULTIVATION-OF-SCIENCE-PART-A. MAR 2004; 78A (2) : 189-191 Al-Co-Ni system exhibits the existence of a stable decagonal phase with various degrees of order in periodic and quasiperiodic planes. Now it is a routine technique to grow macron to cm size rods of the decagonal phase by slow cooling technique. There are attempts to develop nano scale microstructure by various non-equilibrium processing techniques. The aim of the present investigation is to employ mechanical milling (MM) technique for the synthesis of the nano decagonals phases. The alloy ingots have been prepared by melting the constituent pure metals in the induction furnace, and then crushed to around 200 mesh size, as a starting material in the attritor. The milling was performed at 400 rpm under hexane medium with a ball : charge ratio as 20 : 1. During the course of milling, the disordering has been noticed from the broadening of the peaks and lowering of the peak height in the X-ray diffraction patterns. Milled powder after 40 h showed the diffraction peaks confirming the evolution of nano-D phase. The size aspects and the phase constituents has further been confirmed by the transmission electron microscopic investigation. The composition of the as-cast ingot and the milled powder has been analyzed by EDX. [61] SHOCK-INDUCED STRUCTURAL TRANSITIONS AND DYNAMIC STRENGTH OF SOLIDS Mescheryakov-YI; Divakov-AK; Zhigacheva-NI - INTERNATIONAL-JOURNAL-OF-SOLIDS-AND-STRUCTURES. MAY 2004; 41 (9-10) : 2349-2362. Shock tests of series of materials under uniaxial strain conditions including constructional and armor steels, aluminum alloy, copper and beryllium, show that spall-strength sensitively depends on the structural instability of material under compression at the front of compressive pulse. This instability is shown to be a shock-induced structural transition which results in irreversible mesostructure formation in solid. It is also shown that value of structural instability threshold under dynamic compression measured in uniaxial strain tests determines a strength-component of resistance of material to high-velocity penetration in Alekseevskii-Tate model. [60] NANOCRYSTALLINE TIAL POWDERS SYNTHESIZED BY HIGH-ENERGY BALL MILLING: EFFECTS OF MILLING PARAMETERS ON YIELD AND CONTAMINATION Bhattacharya-P; Bellon-P; Averback-RS; Hales-SJ - JOURNAL-OF-ALLOYS-AND-COMPOUNDS. APR 14 2004; 368 (1-2) : 187-196. High-energy ball milling was employed to produce nanocrystalline Ti-Al powders. As sticking of the powders can be sufficiently severe to result in a near zero yield, emphasis was placed on varying milling conditions so as to increase the yield, while avoiding contamination of the powders. The effects of milling parameters such as milling tools, initial state of the powders and addition of process control agents (PCA's) were investigated. Cyclohexane, stearic acid and titanium

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hydride were used as PCA's. Milling was conducted either in a Cr-steel vial with C-steel balls. or in a tungsten carbide (WC) vial with WC balls, using either elemental or pre-alloyed powders. Powder samples were characterized using X-ray diffraction, scanning and transmission electron microscopy. In the absence of PCA's mechanical alloying in a WC vial and attrition milling in a Cr-steel vial were shown to lead to satisfactory yields, about 65-80%, without inducing any significant contamination of the powders. The results suggest that sticking of the powders on to the milling tools is correlated with the phase evolution occurring in these powders during milling. [59] APPLICATION OF MECHANICAL ALLOYING AND SELF-PROPAGATING SYNTHESIS FOR PREPARATION OF STABLE DECAGONAL QUASICRYSTALS Bokhonov-B; Korchagin-A - JOURNAL-OF-ALLOYS-AND-COMPOUNDS. APR 14 2004; 368 (1-2) : 152-156. The X-ray and electron microscopic investigations demonstrated principal possibility to use self-propagation high-temperature synthesis (SHS) in combination with preliminary mechanical activation for the synthesis of stable decagonal quasicrystals. The decagonal quasicrystals formed in SHS process look like faceted decaprisms with a length of 300-400 mum and a thickness of 30-40 mum. SAD patterns are characterized by the presence of the axes of 10- and 2-fold symmetry [58] PRECIPITATION PHASE TRANSFORMATION IN NANOCRYSTALLINE FE-MO ALLOYS Sarkar-S; Bansal-C - JOURNAL-OF-NANOSCIENCE-AND-NANOTECHNOLOGY. JAN-FEB 2004; 4 (1-2) : 203-208. Precipitation phase transformation was studied in nanocrystalline Fe-rich Fe-Mo alloys with the use of X-ray diffraction and Mossbauer spectroscopy. Alloys up to 5 at% Mo in Fe were synthesized by mechanical alloying and formed in a phase bcc solid solutions with average grain sizes in the range of 10-13 nm. The precipitation transformation (alpha --> alpha + lambda ) was found to proceed via a Mo clustering that was correlated with the size of the nanograins. This was understood in terms of the Gibbs Thomson effect with a concept of negative surface energy contribution to the Gibbs free energy of mixing in a nanocrystalline alloy with positive internal energy of mixing. This contribution increased the stability of the solid solution for nanosized grains, and the Mo precipitation started once the grains grew beyond a critical size. We argue that the Mo precipitation takes place in the grain boundary regions, and the Mo-rich lambda phase also precipitates directly in the grain boundary regions, in contrast to the microcrystalline alloys, where the Mo clusters formed within the grains and were first dissolved in the Fe matrix before the lambda phase was formed. [57] EFFECT OF CARBON ON HYDROGEN DESORPTION AND ABSORPTION OF MECHANICALLY MILLED MGH2 Shang-CX; Guo-ZX - JOURNAL-OF-POWER-SOURCES. APR 15 2004; 129 (1) : 73-80. The use of MgH2, instead of pure Mg, in the mechanical synthesis of Mg-based hydrogen storage materials offers added benefit to powder size refinement and reduced oxygen contamination. Alloying additions can further improve the sorption kinetics at a relatively low temperature. This paper examines the effect of graphitic carbon on the desorption and absorption of MgH2. Graphite powder of different concentrations were mechanically milled with MgH2 particles. The milled powder was characterised by XRD, SEM and simultaneous TG and DSC techniques. The results show that graphite poses little influence on the desorption properties of MgH2. However, it does benefit the absorption process, leading to rapid hydrogen uptake in the re-hydrogenated sample. After dehydrogenation, 5 wt.% of hydrogen was re-absorbed within 30 min at 250degreesC for the (MgH2 + 10 G) mixture prior-milled for 8 h, while only 0.8 wt.% for the pure MgH2 milled for 8 h, the effect may be attributed to the interaction between crystalline graphite with H, disassociation close to the MgH, or Mg Surface. Moreover, graphite can also inhibit the formation of a new oxide layer on the surface of Mg particles. [56] MAGNETIC PROPERTIES OF CO-CU METASTABLE SOLID SOLUTION ALLOYS Fan-X; Mashimo-T; Huang-XS; Kagayama-T; Chiba-A; Koyama-K; Motokawa-M - PHYSICAL-REVIEW-B. MAR 2004; 6909 (9) : NIL_696-NIL_701. Metastable solid solution alloy powders and bulk alloys in the cobalt(Co)-copper(Cu) (10-90 mol % Co) system, which is an almost immiscible system at the ambient state, were prepared by mechanical alloying (MA) and shock compression. All MA-treated powders showed the x-ray diffraction patterns of a single phase of fcc structure. The lattice parameter increases with Cu concentration and is fundamentally on the line with Vegard's law. The magnetization curves of CoxCu100-x (x=20-80) metastable bulk alloys at room temperature showed ferromagnetism, while the one of Co10Cu90 system showed paramagnetism. The saturation magnetic moment (M-s) curve versus electron numbers per atom at 0 K was found to be similar to the Slater-Pauling curves of other transition-metal binary systems and decreased with increasing Cu concentration and approached zero at about 28.8 electrons per atom. The magnetoresistance ratio at room temperature increased with Cu content in the ferromagnetic region, while the one of the paramagnetic Co10Cu90 alloy was negligibly small. [55] SOLID STATE SYNTHESIS OF AL-BASED AMORPHOUS AND NANOCRYSTALLINE AL-NB-SI AND AL-ZR-SI ALLOYS Manna-I; Chattopadhyay-PP; Banhart-F; Fecht-HJ - ZEITSCHRIFT-FUR-METALLKUNDE. JUL 2003; 94 (7) : 835-841. This study concerns the development of high-specific-strength Al-based amorphous and/or nanocrystalline alloys by mechanical alloying of Al40TM40Si20 and Al30TM40Si30 (TM = transition metal, Nb and Zr) elemental powder blends by high-energy ball milling. Microstructure of the milled product in different stages of milling has been characterized by X-ray diffraction, high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. Both the systems are amenable to partial solid state amorphisation and development of a composite microstructure comprising varying amounts of nanocrystalline face-centred cubic Nb- or Zr-based solid solution and amorphous phase by appropriate hours of milling. The

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body-centred to face-centred cubic polymorphic change in Nb or Zr seems closely related to grain refinement and plastic strain. [54] TAILORING NANOCRYSTALLINE MATERIALS TOWARDS POTENTIAL APPLICATIONS Klassen-T; Bohn-R; Fanta-G; Oelerich-W; Eigen-N; Gartner-F; Aust-E; Bormann-R; Kreye-H - ZEITSCHRIFT-FUR-METALLKUNDE. MAY 2003; 94 (5) : 610-614. The high interface area in nanocrystalline materials leads to advanced structural and functional properties that are interesting for a variety of applications and products. Three distinct examples for potential applications are given: Nanocrystalline and submicron-sized light-weight intermetallics based on gamma-TiAl exhibiting favourable deformation behaviour at reduced temperatures, nanocrystalline cermet coatings produced by thermal spray process exhibiting improved hardness and wear resistance, and nanocrystalline Mg hydride-based composites for hydrogen storage in future mobile applications exhibiting extremely high, reversible storage capacity and fast kinetics. [53] OXIDE DISPERSION-STRENGTHENED SILVER: MANUFACTURING AND PROPERTIES Grundmann-U; Heilmaier-M; Martin-U; Oettel-H; Schultz-L - ZEITSCHRIFT-FUR-METALLKUNDE. MAY 2003; 94 (5) : 587-592. Novel oxide dispersion-strengthened (ODS) silver alloys were synthesised by mechanical alloying and subsequent consolidation via hot pressing in protective atmosphere. The effect of dispersoid size and volume fraction on the electrical and mechanical properties is exemplified with Cr2O3, CaO and Y2O3 as model candidates for a systematic study of the principles of particle selection. The results for the development of the microstructure under different processing conditions show that control of the impurity level is of primary importance for achieving high-quality, fully dense material. Hence, a modified cryo-milling technique at liquid-N-2 temperature was applied. Data at ambient temperature are presented, revealing that the mechanical and electrical proper-ties can be tailored within a wide range as a function of the microstructure. These results are explained by microstructural concepts for room temperature yielding and electrical conductivity. [52] NANOSTRUCTURE FORMATION AND THERMAL STABILITY OF NANOPHASE MATERIALS PREPARED BY MECHANICAL MEANS Fecht-HJ - ZEITSCHRIFT-FUR-METALLKUNDE. OCT 2003; 94 (10) : 1134-1142. Mechanical attrition, mechanical alloying and other methods of extreme plastic deformation (high pressure torsion, equal channel angular pressing) have been developed as versatile alternatives to other physical and chemical processing routes in preparing nanophase materials. Here several examples are discussed including the deformation-induced nanophase formation in powder particles, in thin-foil sandwich structures and at the surface of alloys exposed to friction-induced wear, leading to the formation of nanocrystals and, in some cases, amorphous nanostructures. This opens exciting perspectives in preparing nanostructured materials with a number of different interface types in terms of structure (crystalline/crystalline, crystalline/amorphous) as well as atomic bond (metal/metal, metal/semiconductor, metal/ ceramic etc.). It is expected that the study of nanostructure formation by mechanical means in the future not only opens new processing routes for a variety of advanced nanophase materials but also improves the understanding of technologically relevant deformation processes on a nanoscopic level. [51] STUDIES ON THE INTERACTION BETWEEN CU NANOPARTICLES AND ZNO NANOPARTICLES WITH EPR AND XPS Wang-ZL; Wu-TH; Yu-JF; Zhu-WC; Yang-PP; Jing-SB; Wang-GJ - CHEMICAL-JOURNAL-OF-CHINESE-UNIVERSITIES-CHINESE. MAR 10 2004; 25 (3) : 550-552. The mixtures of Cu nanoparticles and ZnO nanoparticles were obtained with some physical methods, such as grinding and ultrasionic dispersion and characterized by EPR and XPS. The EPR results showed that no signal could be observed in the Cu EPR spectrum and only a signal g=1. 961 appeared in the ZnO spectrum before they were mixed. After they were mixed, a special signal that could be attributed to Cu2+ was observed in the spectrum. The XPS results showed that the values of the kinetic energy of ZnL3M45M45 and O-1s changed in the XPS spectrum of the mixture, indicating that Zn valance decreased. We could also find that a new 0 species appeared in the mixture. These results showed that there was some interaction between Cu nanoparticles and ZnO nanoparticle, and the model would be Cu-O-Zn. [50] PREPARATION OF Y-FE2O3 NANOPARTICLES BY SOLID (WET)-PHASE GRINDING Jiang-GH; Jiang-JS - CHEMICAL-JOURNAL-OF-CHINESE-UNIVERSITIES-CHINESE. MAR 10 2004; 25 (3) : 405-408. In this paper, a new method to prepare y-Fe2O3 nanoparticles was described. In the presence. of polyethylene glycol (PEG-400), the mixture of FeCl3 (.) 6H(2)O and NaOH was ground and the y-Fe2O3 nanoparticles were prepared. The product obtained was washed and dried at 60 degreesC and calcined at different temperatures for 1 h. XRD, Mossbauer Spectroscopy, TEM, TG-DTA and FTIR were used to characterize the samples. The results show that after dried at 60 degreesC for 2 h, the as-ground sample was transformed into poor-crystalline y-Fe2O3 ultrafine powder. After being calcined at 450 degreesC for 1 h, the ultrafine powder became good-crystalline y-Fe2O3 nanoparticles with particle size of 30 nm. After being calcined at 500 degreesC for 1 h, perfect-crystalline y-Fe2O3 nanoparticles were gotten with a particle size of 40 nm. [49] COMBUSTION SYNTHESIS OF EU-, TB- AND TM- DOPED LN(2)O(2)S (LN = Y, LA, GD) PHOSPHORS Bang-J; Abboudi-M; Abrams-B; Holloway-PH - JOURNAL-OF-LUMINESCENCE. APR 2004; 106 (3-4) : 177-185. Powder phosphors of (Y1-xREx)(2)O2S, (La1-xREx)(2)O2S, and (Gd1-xREx)(2)O2S where RE = EU3+, Tb3+, or Tm3+

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were prepared by combustion reactions from mixed metal nitrate reactants and dithiooxamide (CSNH2)(2) with ignition temperatures of 300-350degreesC. The X-ray diffraction patterns of as-synthesized powders revealed that the Ln(2)O(2)S (Ln=Y, La, and Gd) phase crystallized directly from the combustion reaction with fuel to oxidizer ratios of similar to2.0. Scanning electron microscope images of as-synthesized powders showed a foamy, porous agglomeration and a continuous three-dimensional network. The agglomerates ranged in size between 10 and 30 mum, while the primary particles ranged in size between 100 and 200 nm. The phosphors prepared by combustion reaction were cathodoluminescent and photoluminescent immediately after combustion without additional heating. They exhibited the characteristic emission spectrum of Eu3+, Tb3+, or Tm3+. The cathodoluminescent efficiency of as-synthesized, non-optimized GdO2S:Tb3+ (1.0 mol%) phosphors was lower than that of commercial phosphors at all electron beam energies (30-15% at 1-4kV). Increased water during combustion was shown to favor the formation of oxides or sulfates over oxysulfides. Grinding was shown to reduce and heat treatment was shown to increase the PL intensities [48] EFFICIENT MECHANOCHEMICAL SYNTHESIS OF TRIS(PYRAZOLYLBORATE) COMPLEXES OF MANGANESE(II), COBALT(II) AND NICKEL(II) Kolotilov-SV; Addison-AW; Trofimenko-S; Dougherty-W; Pavlishchuk-VV - INORGANIC-CHEMISTRY-COMMUNICATIONS. APR 2004; 7 (4) : 485-488. A mechanochemical synthesis of Mn(II), Co(II) and Ni(II) tris(pyrazolylborates) (Tp(-)) was developed, which enabled preparation of metal complexes of the type TpMCl and TpMCl.Hpz type (Hpz is the substituted pyrazole generated by hydrolysis of the correspondin g Tp(-) ligand). The X-ray structure of a new Co(II) tris(pyrazolylborate) and the electronic spectra of these coordination compounds are discussed [47] THE SYNTHESIS MECHANISM OF CA3AL2O6 FROM SOFT MECHANOCHEMICALLY ACTIVATED PRECURSORS STUDIED BY TIME-RESOLVED NEUTRON DIFFRACTION UP TO 1000 DEGREES C Mercury-JMR; De-Aza-AH; Turrillas-X; Pena-P - JOURNAL-OF-SOLID-STATE-CHEMISTRY. MAR 2004; 177 (3) : 866-874. The reaction pathway for the Ca3Al2O6 formation up to 1300degreesC, from mechanochemically treated mixtures of amorphous aluminum hydroxide and CaCO3, was studied in situ by differential thermal analysis, constant heating rate dilatometry and time-resolved neutron powder diffraction. The experiment was carried out, in an open system, on a sample with the nominal Ca3Al2O6 stoichiometry. The results obtained by neutron diffractometry and thermal analysis were in good agreement with the data obtained by scanning electron microscopy and X-ray diffraction on heat-treated and-quenched samples. The synthesis path implied the formation of cryptocrystalline Al2O3, crystalline CaO, CaAl2O4 and Ca12Al14O33 as transitory phases. Finally the nucleation and growth of the single phase Ca3Al2O6 took place at 1300degreesC and exhibited porous structure due to CO2 and H2O release. [46] MECHANOCHEMICAL-HYDROTHERMAL SYNTHESIS OF CALCIUM PHOSPHATE POWDERS WITH COUPLED MAGNESIUM AND CARBONATE SUBSTITUTION Suchanek-WL; Byrappa-K; Shuk-P; Riman-RE; Janas-VF; TenHuisen-KS - JOURNAL-OF-SOLID-STATE-CHEMISTRY. MAR 2004; 177 (3) : 793-799. Magnesium- and carbonate-substituted calcium phosphate powders (Mg-, CO3-CaP) with various crystallinity levels were prepared at room temperature via a heterogeneous reaction between MgCO3/Ca(OH)(2) powders and an (NH4)(2)HPO4 Solution using the mechanochemical-hydrothermal route. X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis were performed. It was determined that the powders containing both Mg2+ and CO32- ions were incorporated uniformly into all amorphous calcium phosphate phase while in contrast, the as-prepared powder free of these dopants was crystalline phase-pure, stoichiometric hydroxyapatitc. Dynamic light scattering revealed that the average particle size of the room temperature Mg-, CO3-CaP powders was in the range of 482 nm-700 nm nm with a specific surface area between 53 and 91 m(2)/g. Scanning clectron microscopy confirmed that the Mg-, CO3-CaP powders consisted of agglomerates of equiaxed, 20-35 nm crystals. [45] CATALYTIC PROPERTIES OF MECHANICALLY ACTIVATED HUMIC SUBSTANCES IN ELECTROREDUCTION OF OXYGEN Yudina-NV; Savel'-eva-AV; Ivanov-AA; Korotkova-EI; Lomovskii-OI - RUSSIAN-JOURNAL-OF-APPLIED-CHEMISTRY. JAN 2004; 77 (1) : 46-50. Effect of mechanical treatment of peat on the yield of the major fractions (polysaccharides, polyphenols, water-soluble compounds, and humic acids) and catalytic activity of humic substances in oxidation processes is studied. Conditions of formation of substances with the maximal antioxidant and initiating activities are determined. The antioxidant and initiating activities of the polysaccharide and humic fractions is studied, in relation to the structure and iron content. [44] A study of the effect of aluminium on the mechanochemical reduction of hematite by graphite Khaki-JV; Panjehpour-M; Kashiwaya-Y; Ishii-K; Bafghi-MSS - STEEL-RESEARCH-INTERNATIONAL. MAR 2004; 75 (3) : 169-177. The effect of addition of small amounts of aluminium on mechano-chemical reduction of hematite by graphite was studied. Various amounts of aluminium (0 to 10%) were added to a hematite-graphite mixture, in which C/O ratio was 1:1. The hematite-graphite-aluminium mixtures were then subjected to ball milling followed by heating up reduction. The heating up

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reduction was carried out in Ar atmosphere, using TG-DTA device. In TG-DTA experiments, samples were heated by a constant heating rate of 10 degreesC/min from room temperature up to 1100 degreesC and maintained for 30 minutes at this temperature. To clarify the reactions which took place during milling and heating up reduction, the samples were subjected to XRD examinations. It was found that the heat generated during exothermic reaction of aluminothermic reduction of hematite promoted the endothermic reaction of carbothermic reduction. In the course of heating up reduction, the carbothermic reaction occurred just after aluminothermic reaction. Increasing of aluminum content from 0 to 10% in 2 hours ball milled samples decreased the temperature of carbothermic reaction from 1020 degreesC to about 860 degreesC. The further ball milling of the samples up to 5 and 10 hours, for the samples containing 10 and 5% aluminium respectively, caused the decrease of the temperature of aluminothermic and carbothermic reactions to around the melting point of aluminium. [43] HYDRIDING/DEHYDRIDING PROPERTIES OF LA2MG16NI ALLOY PREPARED BY MECHANICAL BALL MILLING IN BENZENE AND UNDER ARGON Chi-HZ; Chen-CP; Chen-LX; An-Y; Wang-QD - INTERNATIONAL-JOURNAL-OF-HYDROGEN-ENERGY. JUL 2004; 29 (7) : 737-741. The hydrogen storage properties of La2Mg16Ni alloy prepared by mechanical milling in benzene or under argon were investigated. The scanning electron microscope results show that there are obvious differences in the surface morphology for different ball milling conditions. Compared with the sample milled under argon, the alloy milled in benzene has relatively faster absorption/desorption kinetics. Furthermore, the milling in benzene destabilizes the alloy hydride. The ball milling in organic solvent offers a new way for magnesium-based hydrogen storage materials, exploiting their higher capacity and higher equilibrium pressure while operating at lower temper [42] SYNTHESIS AND CHARACTERIZATIONS OF NANOCRYSTALLINE WC-CO COMPOSITE POWDERS BY A UNIQUE BALL MILLING PROCESS Shen-J; Sun-JF; Zhang-FM - JOURNAL-OF-MATERIALS-SCIENCE-AND-TECHNOLOGY. JAN 2004; 20 (1) : 7-10. In order to explore the high efficiency of fabricating nanocrystalline WC-Co composite powders, this paper presented, a unique high energy ball milling process with variable rotation rate and repeatious circulation, by which nanocrystalline WC-10Co-0.8VC-0.2Cr(3)C(2) (wt pct) composite powders with mean grain size of 25 nm were prepared in 32 min, and the quantity of the powders for a batch was as much as 800 grams. The as-prepared powders were analyzed and characterized by chemical analysis, X-ray diffraction (XRD), transmission electron microscopy (TEM) and differential thermal analysis (DTA). The results show that high energy ball milling with variable rotation rates and repeatious circulation could be used to produce nanocrystalline WC-Co powder composites with high efficiency. The compositions of the powders, meet its specifications with low impurity content. The mean grain size decreases, lattice distortion and system energy increase with increasing the milling time. The morphology of nanocrystalline WC-Co particles displays dominantly sphere shape and their particle sizes are all lower than 80 nm. The eutectic temperature of the nanocrystalline WC-10Co-0.8VC-0.2Cr(3)C(2) composites is about 1280degreesC [41] NEURAL NETWORK MODELING AND CONTROL OF CEMENT MILLS USING A VARIABLE STRUCTURE SYSTEMS THEORY BASED ON-LINE LEARNING MECHANISM Topalov-AV; Kaynak-O - JOURNAL-OF-PROCESS-CONTROL. AUG 2004; 14 (5) : 581-589. It is well known that the major cause of instability in industrial cement ball mills is the so-called plugging phenomenon. A novel neural network adaptive control scheme for cement milling circuits that is able to fully prevent the mill from plugging is presented. Estimates of the one-step-ahead errors in control signals are calculated through a neural predictive model and used for controller tuning. A robust on-line learning algorithm, based on sliding mode control (SMC) theory is applied to both: to the controller and to the model as well. The proposed approach allows handling of mismatches, uncertainties and parameter changes in the model of the mill. The simulation results from indicate that both the neural model and the controller inherit the major advantages of SMC, i.e. robustness. Furthermore, learning is achieved in a rapid manner [40] COLLAGEN PROCESSING Maffia-GJ; Selter-MA; Cooke-PH; Brown-EM - JOURNAL-OF-THE-AMERICAN-LEATHER-CHEMISTS-ASSOCIATION. APR 2004; 99 (4) : 164-169. Collagen dispersions, produced from fibrils recovered from milled bovine collagen, have shown promise in environmental remediation in applications as settling aids, filtration aids, fractionation media, oil drop stabilizers, and water purification aids. Macroporous structures, processed by controlled lyophilization of collagen dispersions, are suitable as cell culturing substrates. Collagen was structurally characterized during milling to assist in designing a method for scale-up of the production process. In fact, although the initial processing involves a ball mill, the actual operation is more of an unraveling of the fiber to expose the fibrils, which have nanoscale dimensions. During the ball-milling step of production the active surface area of the collagen increases more than 200 times without chemically altering or denaturing the collagen. To demonstrate this throughout the milling process, active surface area per mass, fibril structure, molecular weight distribution, percent lipid, percent nitrogen, and percent ash were monitored. [39] MAGNETIC PROPERTIES OF MECHANICALLY ALLOYED AND ANNEALED POWDERS FE-100-XCX (X=5 AND 15 AT.%)

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Ul'-yanov-AI; Elsukov-EP; Zagainov-AV; Arsent'-eva-NB; Dorofeev-GA; Fomin-VM - RUSSIAN-JOURNAL-OF-NONDESTRUCTIVE-TESTING. SEP 2003; 39 (9) : 683-696. The effect of the structural state and the phase composition on the magnetic hysteresis properties of Fe(95)C(5) and Fe(85)C(15) powders after mechanical alloying and annealing is investigated. It is shown that in the initial stage of grinding in a ball planetary mill the coercive force of the Fe-C powders is determined by the degree of defectiveness of the alpha-Fe phase and the relative volume and dimensions of nonmagnetic graphitic inclusions in iron powder particles. As the grinding time increases, the alpha-Fe phase goes over into a nanostructure state and carbon from graphite inclusions goes over into an amorphous Am(Fe-C) phase. After annealing on the temperature interval 300-600degreesC, the amorphous Am(Fe-C) phase is transformed into Fe3C ferric carbide. The coercive force of the Fe3C phase strongly depends on the degree of distortion of its crystal lattice and amounts to similar to 80 A/cm for the phase with distorted lattice and similar to 240 A/cm for the phase with equilibrium undistorted lattice. The magnetic characteristics of the powder after mechanical alloying and subsequent annealing are determined by the type, amount, and structural state of the phases containing in the samples. [38] HYDROGEN STORAGE IN PROTON-CONDUCTIVE PEROVSKITE-TYPE OXIDES AND THEIR APPLICATION TO NICKEL-HYDROGEN BATTERIES Esaka-T; Sakaguchi-H; Kobayashi-S - SOLID-STATE-IONICS. JAN 2004; 166 (3-4) : 351-357. In order to obtain a new anode material of hydrogen battery, perovskite-type oxide powders were prepared by a conventional solid-state reaction method and a subsequent mechanical milling using a planetary ball-milling machine. Hydrogen charge and discharge properties were investigated electrochemically in a three-electrode cell with KOH solution. As a result, the sample shown by ACe(1-x)M(x)O(3-delta) (A = Sr or Ba, M = rare earth element) was found to store hydrogen in the bulk and repeat hydrogen charge and discharge at room temperature, which suggested that the oxides are candidates for anode materials of hydrogen batteries. The maximum content of hydrogen stored was 119 mA It g(-1) for BaCe0.95N0.05O3-delta, which corresponded to the fact that 1.44 hydrogen atoms were present in one formula of the sample. However, the cycleability was degraded with increasing the cycle number. Considering higher hydrogen-storage performance in the cerium-containing perovskite-type oxides than in the others, the valence change in cerium would have an important role to store hydrogen. Furthermore, the fact that the 1.44 hydrogens stored exceed the number of cerium in the formula Suggested the presence of atomic hydrogen in the perovskite-type oxide like in the hydrogen storage alloys. [37] A STUDY OF THE EFFECT OF ALUMINIUM ON THE MECHANOCHEMICAL REDUCTION OF HEMATITE BY GRAPHITE Khaki-JV; Panjehpour-M; Kashiwaya-Y; Ishii-K; Bafghi-MSS - STEEL-RESEARCH-INTERNATIONAL. MAR 2004; 75 (3) : 169-177. The effect of addition of small amounts of aluminium on mechano-chemical reduction of hematite by graphite was studied. Various amounts of aluminium (0 to 10%) were added to a hematite-graphite mixture, in which C/O ratio was 1:1. The hematite-graphite-aluminium mixtures were then subjected to ball milling followed by heating up reduction. The heating up reduction was carried out in Ar atmosphere, using TG-DTA device. In TG-DTA experiments, samples were heated by a constant heating rate of 10 degreesC/min from room temperature up to 1100 degreesC and maintained for 30 minutes at this temperature. To clarify the reactions which took place during milling and heating up reduction, the samples were subjected to XRD examinations. It was found that the heat generated during exothermic reaction of aluminothermic reduction of hematite promoted the endothermic reaction of carbothermic reduction. In the course of heating up reduction, the carbothermic reaction occurred just after aluminothermic reaction. Increasing of aluminum content from 0 to 10% in 2 hours ball milled samples decreased the temperature of carbothermic reaction from 1020 degreesC to about 860 degreesC. The further ball milling of the samples up to 5 and 10 hours, for the samples containing 10 and 5% aluminium respectively, caused the decrease of the temperature of aluminothermic and carbothermic reactions to around the melting point of aluminium [36] ON THE BEHAVIOUR OF HEMATITE AND GRAPHITE BLEND DURING BALL MILLING AND HEATING UP REDUCTION OF MILLED MIXTURE Raygan-S; Khaki-JV; Aboutalebi-MR - STEEL-RESEARCH-INTERNATIONAL. MAR 2004; 75 (3) : 163-168. The effect of ball milling under argon and air atmospheres on the reaction behaviour of the mixture of sintered hematite and graphite was investigated. Thermo-gravimetry / differential thermal analysis (TG-DTA) was adopted to determine the effect of milling time on the reduction process during heating up under Ar atmosphere. The samples were heated at a constant heating rate of 10 degreesC/min from room temperature up to 1100 degreesC and maintained at this temperature for 30 minutes. TGL (thermo-gravimetry loss) curves showed a decrease of onset temperature of reduction with increase of milling time. XRD patterns of milled samples at room temperature revealed that the peaks of graphite disappeared after 48 hours milling. This represents the transformation of crystalline structure of graphite to the amorphous structure. By increasing the milling time to 72 hours, magnetite peaks appeared in the XRD pattern as a result of reduction of hematite with graphite during milling. However, the amount of magnetite formed during milling process increased as milling proceeded. The powders milled under Ar atmosphere became more active than the powders milled under air and consequently the carbothermic reduction of hematite in powders milled under Ar atmosphere was observed at lower temperatures compared with air-milled powders. It was observed that the reduction time of hematite in powder mixture was decreased with increase

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of sintering time of hematite prior to milling. [35] X-RAY DIFFRACTION AND MOSSBAUER STUDIES OF NANOCRYSTALLINE FE-NI ALLOYS PREPARED BY MECHANICAL ALLOYING Djekoun-A; Bouzabata-B; Otmani-A; Greneche-JM - CATALYSIS-TODAY. MAR 30 2004; 89 (3) : 319-323 Mechanical alloying is a powder metallurgy processing technique involving cold welding, fracturing, and rewelding of powder particles in a high-energy ball mill. Mechanical alloying is a non-equilibrium process for materials synthesis. It has been used to obtain nanocrystalline binary Fe-Ni system. Elemental powders of iron and nickel (Fe-50 at.% Ni) have been mixed in a planetary mill. The structural effects of mechanical alloying of powders were investigated by scanning electron microscopy, X-ray diffraction analysis and Mossbauer spectroscopy. It is observed a gradual formation of mixture of phases as fcc (gamma) with a nanoscale grain size. In addition, as the average grain size is decreased with a progressive enlargement of peaks of X-ray diffraction, a paramagnetic phase appears after 48 h of ball milling detected by Mossbauer spectroscopy. [34] HYDRIDING/DEHYDRIDING PROPERTIES OF LA2MG16NI ALLOY PREPARED BY MECHANICAL BALL MILLING IN BENZENE AND UNDER ARGON Chi-HZ; Chen-CP; Chen-LX; An-Y; Wang-QD - INTERNATIONAL-JOURNAL-OF-HYDROGEN-ENERGY. JUL 2004; 29 (7) : 737-741. The hydrogen storage properties of La2Mg16Ni alloy prepared by mechanical milling in benzene or under argon were investigated. The scanning electron microscope results show that there are obvious differences in the surface morphology for different ball milling conditions. Compared with the sample milled under argon, the alloy milled in benzene has relatively faster absorption/desorption kinetics. Furthermore, the milling in benzene destabilizes the alloy hydride. The ball milling in organic solvent offers a new way for magnesium-based hydrogen storage materials, exploiting their higher capacity and higher equilibrium pressure while operating at lower temperature. [35] MECHANICAL SYNTHESIZED NANOCRYSTALLINE TI/AL COMPOSITE POWDERS AS PRECURSOR FOR TI/AL ALLOY VIA REACTIVE SINTERING Hu-LX; Li-XQ; Wang-E - JOURNAL-OF-ADVANCED-MATERIALS. APR 2004; 36 (2) : 30-34. TiAl alloy and powders with high purity and low oxygen contents were synthesized by ICS. Its densification was studied by both hot isostatic pressing (HIP) and conventional press-sintering process. The samples, with density of more than 3.75g/cm(3), were obtained by HIP at 196 MPa and 1250degrees C for 3h. The microstructure consisted of equiaxed grains and a small volume fraction of lamellar structure. The compressive tests showed the yield strength of TiAl sample was 646 MPa, the compressive strength was 1579 MPa and compressive ductility was above 26%. The addition of Mn and Cr changed the structure, and increased the volume of alpha(2) phase. The density of the powder compact sintered directly might reach the value of theoretical density. [34] NANOCRYSTALLINE AG-FE-SN ANODE MATERIALS FOR LI-ION BATTERIES Yin-JT; Wada-M; Tanase-S; Sakai-T - JOURNAL-OF-THE-ELECTROCHEMICAL-SOCIETY. 2004; 151 (4) : A583-A589. The Ag-Fe-Sn alloy powders prepared by mechanical alloying technique have been studied as anode material for lithium-ion batteries. The half-cell tests with lithium counter electrode revealed that a suitable substitution of Fe for Ag led to a significant improvement of the cycling performance of the electrodes. Among these electrodes, the Ag36.4Fe15.6Sn48 electrode was found to be capable of keeping a rechargeable capacity of about 280 mAh/g over 300 cycles, which was better than that of the Fe-free Ag52Sn48 electrode. Typically, the structural changes of the Ag26Fe26Sn48 electrode during Li insertion and/or extraction were characterized using the combined techniques involving X-ray diffraction, high resolution transmission electron microscopy, selected area electron diffraction, and energy dispersive X-ray spectrometry. It is considered that the electrochemical properties of these electrodes are associated with their microstructure and morphology, such as the distribution of intermetallic compound Ag3Sn in Sn matrix, the Ag3Sn/Sn ratio as well as the presence of inactive Fe. [33] MECHANISM OF LITHIUM INSERTION INTO MAGNESIUM SILICIDE Roberts-GA; Cairns-EJ; Reimer-JA - JOURNAL-OF-THE-ELECTROCHEMICAL-SOCIETY. 2004; 151 (4) : A493-A496. The reaction mechanism for electrochemical lithium insertion into magnesium silicide was studies by in situ and ex situ X-ray diffraction (XRD). Lithium intercalation during the initial stages of insertion was indicated by a slight shift toward lower angles in the diffraction patterns. Upon further insertion, Li2MgSi was formed. This was indicated by the appearance of magnesium peaks, the disappearance of Mg2Si peaks, and the appearance of Li2MgSi peaks in the diffraction patterns. Magnesium XRD peaks that accumulated during cycling indicated that the formation of Mg2Si during lithium removal was not entirely reversible. Li2MgSi was synthesized by mechanical alloying. XRD patterns and nuclear magnetic resonance spectra of the mechanically alloyed and electrochemically produced phases are compared. [32] BULK GLASS FORMING AND THERMAL STABILITY IN FE67.0CO9.5ND3.0DY0.5B20 ALLOY Parida-S; Ram-S; Eckert-J; Roth-S; Loser-W; Schultz-L - MATERIALS-LETTERS. MAY 2004; 58 (12-13) : 1844-1852. Bulk glass forming ability (GFA) of a multicomponent alloy of Fe67.0Co9.5Nd3.0Dy0.5B20 is studied by synthesizing it in shapes of thin ribbons, rods or cylinders, or pellets. The three samples are obtained with three different methods of melt

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spinning, copper mold casting, or mechanical attrition (of ribbons) followed by a hot compaction of derived alloy powder, respectively. A melt-spun ribbon of 50- to 100-mum thickness has a truly amorphous structure with two X-ray diffraction halos of wavevectors q(1) = 14.2 and q(3) = 33.0 nm(-1). A modified diffractogram consists of two halos q(1) = 14.5 and q(2) = 19.0nm(-1) in the rods (3.0-mm diameter) while of three halos q(1) = 13.4,q(2) = 15.0andq(3) = 24.0 q(3) = 24.0 nm(-1) in the pellets (5- to 10-mm diameter and 3- to 5-mm thickness). A small value of coercivity H-c of 7.1 kA/m in the rods or almost zero in the ribbons reveals soft magnetic behaviors characteristic of an amorphous structure of the alloy. An improved value of H-c = 188.5 kA/m develops in the hot compressed pellets of the powder at similar to 630 degreesC temperature. The pellets have some recrystallized alpha-Fe, Fe3B and R2Fe14B (R=Nd or Dy) nanocrystallites in a bulk amorphous composite structure. The results are analyzed with thermal analysis and microstructures of the samples. [31] MAGNETIC PROPERTIES OF MECHANICALLY ALLOYED AND ANNEALED POWDERS FE-100-XCX (X=5 AND 15 AT.%) Ul'-yanov-AI; Elsukov-EP; Zagainov-AV; Arsent'-eva-NB; Dorofeev-GA; Fomin-VM - RUSSIAN-JOURNAL-OF-NONDESTRUCTIVE-TESTING. SEP 2003; 39 (9) : 683-696. The effect of the structural state and the phase composition on the magnetic hysteresis properties of Fe(95)C(5) and Fe(85)C(15) powders after mechanical alloying and annealing is investigated. It is shown that in the initial stage of grinding in a ball planetary mill the coercive force of the Fe-C powders is determined by the degree of defectiveness of the alpha-Fe phase and the relative volume and dimensions of nonmagnetic graphitic inclusions in iron powder particles. As the grinding time increases, the alpha-Fe phase goes over into a nanostructure state and carbon from graphite inclusions goes over into an amorphous Am(Fe-C) phase. After annealing on the temperature interval 300-600degreesC, the amorphous Am(Fe-C) phase is transformed into Fe3C ferric carbide. The coercive force of the Fe3C phase strongly depends on the degree of distortion of its crystal lattice and amounts to similar to 80 A/cm for the phase with distorted lattice and similar to 240 A/cm for the phase with equilibrium undistorted lattice. The magnetic characteristics of the powder after mechanical alloying and subsequent annealing are determined by the type, amount, and structural state of the phases containing in the samples. [30] HYDROGEN STORAGE IN PROTON-CONDUCTIVE PEROVSKITE-TYPE OXIDES AND THEIR APPLICATION TO NICKEL-HYDROGEN BATTERIES Esaka-T; Sakaguchi-H; Kobayashi-S - SOLID-STATE-IONICS. JAN 2004; 166 (3-4) : 351-357. In order to obtain a new anode material of hydrogen battery, perovskite-type oxide powders were prepared by a conventional solid-state reaction method and a subsequent mechanical milling using a planetary ball-milling machine. Hydrogen charge and discharge properties were investigated electrochemically in a three-electrode cell with KOH solution. As a result, the sample shown by ACe(1-x)M(x)O(3-delta) (A = Sr or Ba, M = rare earth element) was found to store hydrogen in the bulk and repeat hydrogen charge and discharge at room temperature, which suggested that the oxides are candidates for anode materials of hydrogen batteries. The maximum content of hydrogen stored was 119 mA It g(-1) for BaCe0.95N0.05O3-delta, which corresponded to the fact that 1.44 hydrogen atoms were present in one formula of the sample. However, the cycleability was degraded with increasing the cycle number. Considering higher hydrogen-storage performance in the cerium-containing perovskite-type oxides than in the others, the valence change in cerium would have an important role to store hydrogen. Furthermore, the fact that the 1.44 hydrogens stored exceed the number of cerium in the formula Suggested the presence of atomic hydrogen in the perovskite-type oxide like in the hydrogen storage alloys. [29] XRD LINE BROADENING ANALYSIS WITH BALL MILLED PALLADIUM Lucks, I; Lamparter, P; Xu, J; Mittemeijer, EJ - Editors: Andersson, Y; Mittemeijer, EJ; Welzel, U - EUROPEAN POWDER DIFFRACTION EPDIC 8 119-122, 2004 -MATERIALS SCIENCE FORUM, 443-4 - 8th European Powder Diffraction Conference - Uppsala, SWEDEN, MAY 23-26, 2002 Palladium powder was deformed by ball milling under an argon atmosphere in two types of mills for different milling times. Two methods for X-ray diffraction line profile analysis, the Williamson-Hall method and the Warren-Averbach method, yielded similar trends, but different quantitative results for crystallite sizes (column lengths) and microstrains. With both methods, from the anisotropic line broadening for planetary milled Pd smaller crystallite sizes and larger microstrains were obtained along the <100> direction than along <111>. Milling in a shaker mill causes microstrain higher by a factor of about two than milling in a planetary mill. The evolution of the crystallite size upon milling was discussed in terms of bimodal size distributions. [28] THE MICROSTRUCTURE OF MECHANICALLY ALLOYED NANOCRYSTALLINE ALUMINIUM-MAGNESIUM Gubicza, J; Kassem, M; Ungar, T - Editors: Andersson, Y; Mittemeijer, EJ; Welzel, U - EUROPEAN POWDER DIFFRACTION EPDIC 8 103-106, 2004 - MATERIALS SCIENCE FORUM, 443-4 - 8th European Powder Diffraction Conference, Uppsala, SWEDEN, MAY 23-26, 2002 The effect of the nominal Mg content and the milling time on the microstructure of mechanically alloyed Al(Mg) solid solutions is studied. The crystallite size distribution and the dislocation structure are determined by X-ray diffraction peak profile analysis. Magnesium gradually goes into solid solution during ball milling and after 3 h almost all of the Mg atoms are soluted into the Al matrix. With increasing milling time the Mg content in solid solution, the dislocation density as well as the hardness are increasing, whereas the crystallite size is decreasing. A similar tendency of these parameters is observed at a particular duration of ball milling with increasing of the nominal Mg content. At the same time for a long milling period

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the dislocation density slightly decreases together with a slight reduction of the hardness. [27] THERMOELECTRIC PROPERTIES OF ZN4SB3 PREPARED BY MECHANICAL ALLOYING Kim, IH; Ur, SC - TWENTY-SECOND INTERNATIONAL CONFERENCE ON THERMOELECTRICS, PROCEEDINGS ICT '03 275-278, 2003 - 22nd International Conference on Thermoelectrics (ICT 03), La Grande Motte, FRANCE, AUG 17-21, 2003 - Conference Sponsors: Univ Montpellier 2, Lab Physicochim Matiere Condensee, Univ Nancy 1, Lab Phys Materiaux Thermoelectric Zn4Sb3 bulk specimens were produced by mechanical alloying of elemental powders and consolidated by hot pressing. Single phase Zn4Sb3 was not obtained using a nominal stoichiometric composition, but near single phase Zn4Sb3 with remnant elemental Zn having a relatively high density was produced using nominally 11.7 at% Zn-rich powders. Phase transformations during mechanical alloying were systematically investigated. Thermoelectric properties and transport parameters were evaluated for the hot pressed specimens and compared with results of analogous studies. [25] MECHANICAL ALLOYING AND THERMOELECTRIC PROPERTIES OF CO DOPED FESI2 Ur, SC - TWENTY-SECOND INTERNATIONAL CONFERENCE ON THERMOELECTRICS, PROCEEDINGS ICT '03 149-152, 2003 - 22nd International Conference on Thermoelectrics (ICT 03) La Grande Motte, FRANCE, AUG 17-21, 2003, Conference Sponsors: Univ Montpellier 2, Lab Physicochim Matiere Condensee, Univ Nancy 1, Lab Phys Materiaux Mechanical alloying process has been used to produce a Co doped iron-silicide. As-milled powders were of metastable state and fully transformed to beta-FeSi2 phase by subsequent isothermal annealing. Mechanically alloyed powders were successfully consolidated by vacuum hot pressing. As-consolidated iron silicides consisted of untransformed mixture of alpha-Fe2Si5 and epsilon-FeSi phases. Subsequent isothermal annealing at 830degreesC in vacuum led to the thermoelectric semiconducting beta -FeSi2 phase transformation. Fraction beta-FeSi2 increased with annealing time and saturated at 100 hours of annealing. Thermoelectric properties of Co doped iron-silicide after isothermal annealing as a function of temperature were investigated from room temperature to 600 K. Transport properties at room temperature were also evaluated in this study. [24] PREPARATION AND THERMAL TRANSPORT PROPERTIES OF COSB3 NANO-COMPOUNDS Yu, BL; Tang, XF; Zhang, QJ; Liu, TX; Luo, PF; Wang, J - TWENTY-SECOND INTERNATIONAL CONFERENCE ON THERMOELECTRICS, PROCEEDINGS ICT '03 101-104, 2003 - 22nd International Conference on Thermoelectrics (ICT 03) , La Grande Motte, FRANCE, AUG 17-21, 2003 - Conference Sponsors: Univ Montpellier 2, Lab Physicochim Matiere Condensee, Univ Nancy 1, Lab Phys Materiaux CoSb3 micrometer powder was synthesized by solid-state reaction using high purity powder of Co, Sb as the starting materials. CoSb3 nano-powder and block material with nanostructure were prepared by high-energy ball-milling and by Spark Plasma Sintering (SPS), respectively. The influence of mass ratio of big balls and small balls, milling speed and time on particles size of CoSb3 powder, and sintering temperature and time on grains size of CoSb3 were investigated. The influence of nanostructure on thermal transport properties of CoSb3 was also studied. [23] THE EFFECT OF VARIOUS DOPANTS ON THERMOELECTRIC PROPERTIES OF BI-2(TE0.9SE0.1)(3) POLYCRYSTALS Nozue, A; Park, YH; Kawasaki, A - TWENTY-SECOND INTERNATIONAL CONFERENCE ON THERMOELECTRICS, PROCEEDINGS ICT '03 31-33, 2003 - 22nd International Conference on Thermoelectrics (ICT 03) - La Grande Motte, FRANCE, AUG 17-21, 2003, Conference Sponsors: Univ Montpellier 2, Lab Physicochim Matiere Condensee, Univ Nancy 1, Lab Phys Materiaux In this study, mechanical alloying followed by pulse discharge sintering (MA-PDS) was employed to synthesize the bulk Bi-2(Te0.9Se0.1)(3) thermoelectric materials and then the compacts were spread by hot-pressing process. The additives we selected several metal iodide and bromide(AgBr, CuBr, CuBr2, AgI). All dopants increase the carrier concentration and power-factor. The excellent metal element of dopants were silver and copper. Moreover, the effect of spreading on the crystal orientation and thermoelectric performance of the compacts was investigated. The microstructural characterizations of the spread compacts by XRD and SEM indicated a high crystallographic orientation after spreading. Furthermore, power-factor and carrier mobility was increased by the high crystal orientation. [22] INFLUENCE OF COMPOSITION AND TEXTURE ON THE THERMOELECTRIC AND MECHANICAL PROPERTIES OF EXTRUDED (BI1-XSBX)(2) (TE1-YSEY)(3) ALLOYS Simard, JM; Vasilevskiy, D; Turenne, S - TWENTY-SECOND INTERNATIONAL CONFERENCE ON THERMOELECTRICS, PROCEEDINGS ICT '03 13-18, 2003 - 22nd International Conference on Thermoelectrics (ICT 03) , La Grande Motte, FRANCE, AUG 17-21, 2003, Conference Sponsors: Univ Montpellier 2, Lab Physicochim Matiere Condensee, Univ Nancy 1, Lab Phys Materiaux This paper presents the results obtained after five years of process development to produce bismuth telluride based thermoelectric alloys by powder consolidation approach. The synthesis of the alloys is obtained by mechanical alloying from pure elemental powders. Billets are then produced by cold pressing followed by hot extrusion in order to have a fully dense polycrystalline product with a crystal texture characterized by the c-axis aligned perpendicularly to the extrusion direction. Semiconductors of type-n and type-p were produced by carefully controlling the chemical composition of the alloys and the

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concentration of doping agents. The evolution of the thermoelectric properties is given as a function of the constituents contents of the alloy to determine an optimal composition that leads to maximum value of the figure of merit. The effect of texture is measured not only on the thermoelectric properties but also on the mechanical behaviour of the material. [21] CONTINUUM MECHANICAL FUNDAMENTALS OF MECHANOCHEMISTRY Levitas-VI - HIGH-PRESSURE-SURFACE-SCIENCE-AND-ENGINEERING. 2004; : 161-292 [20] TWO POLYMORPHS OF A TETRAMETHYLAMMONIUM ZINCOPHOSPHATE WITH DIAMOND NET-RELATED FRAMEWORKS CONTAINING [H3O4(P)(4)] HYDROXYL NESTS: SOLUTION-MEDIATED AND MECHANOCHEMICAL PHASE TRANSFORMATIONS AND CRYSTAL STRUCTURES Wiebcke-M; Marler-B - SOLID-STATE-SCIENCES. FEB 2004; 6 (2) : 213-223. The formation and crystal structures of two polymorphs of the tetramethylammonium zincophosphate (ZnPO) (NMe4)[ZnP2O8H3] have been reinvestigated. Methods employed were single-crystal and powder X-ray diffraction, thermogravimetic and difference thermal analysis and C-13 and P-31 solid state NMR spectroscopy. The following new findings are reported: The polymorphs formulated as (NMe4)[Zn(HPO4)(H2PO4)] (1) and (NMe4)[Zn(H1.5PO4)(2)] (H) crystallize from clear solutions near room temperature. A solution-mediated reversible phase transformation readily occurs with I and 11 being the thermodynamical stable phase at room temperature and 50degreesC, respectively. In the solid state these transformations are very sluggish. Solid I can be mechanochemically transformed into II (grinding at room temperature for ca. 30 min). Both polymorphs possess interrupted 3D open-framework structures that are closely related to the diamond net and contain different kinds of distorted tetrahedral [H3O4(P)(4)] groupings (hydroxyl nests). Formal substitution of the three protons in each hydroxyl nest by a trivalent cation results in fully four-connected frameworks with a novel topology (in the case of I) and the gismondine topology (11). ZnPO and cobalt(II) phosphate (CoPO) materials with framework structures that contain [HxO4(P)(4)] hydroxyl nests (x = 3 or 4) and/or being related to the diamond net are briefly surveyed. [19] HOMOGENEITY FIELD AND MAGNETORESISTANCE OF THE CA(MN, CU)(7)O-12 SOLID SOLUTION PREPARED IN OXYGEN Pomerantseva-EA; Itkis-DM; Goodilin-EA; Noudem-JG; Lobanov-MV; Greenblatt-M; Tretyakov-YD - JOURNAL-OF-MATERIALS-CHEMISTRY. 2004; 14 (7) : 1150-1156. CaMn3-xCuxMn4O12 solid solution (0 less than or equal to x less than or equal to 1.5) was prepared in pure oxygen at 850 degreesC and ambient pressure. The compound was synthesized either with KCl, added as a mineralizer to precursors, or annealing the mechanically activated oxide precursor. These synthetic methods allowed optimization of the microstructure of the samples to reproducibly yield the record negative magnetoresistance of -65% at 35 K in a field of 5 T, for x = 1.0. [18] SYNTHESIS AND ELECTROCHEMICAL PERFORMANCE OF LICRXMN2-XO4 POWDERS BY MECHANICAL ACTIVATION AND ROTARY HEATING AU: Song-GM; Wang-YJ; Zhou-Y - JOURNAL-OF-POWER-SOURCES. APR 5 2004; 128 (2) : 270-277. Mechanical activation followed by rotary heating has been successfully applied to the synthesis of Cr-doped lithium manganese oxide (LiMn2O4) powders. The precursor of LiCrxMn2-xO4 for Li-ion batteries has been synthesized from LiOH.H2O, MnO2, and Cr2O3 as starting materials by mechanical activation, which ensured a high level of homogeneity in the chemical composition of the precursor and resulted in a reduction in the synthesis temperature and heating time. Highly crystallized LiCrxMn2-xO4 (0.04 less than or equal to x less than or equal to 0.10) powders were obtained by subsequent rotary heating of the precursor at 550-750degreesC for 2 h. Rotary heating enhanced the experimental control in chemical composition, particle size distribution and microstructure of the final products. The optimum mechanical activation condition was determined based on XRD analysis. The synthesized LiCrxMn2-xO4 powder has a narrow particle size distribution, high discharge capacities and good cyclability. The method of mechanical activation combined with rotary heating should be an excellent technique of decreasing synthesis temperature and shortening heating time, and enhancing the uniformity of particle size of the product. [17] INFLUENCE OF THE FINENESS OF SEWAGE SLUDGE ASH ON THE MORTAR PROPERTIES Pan-SC; Tseng-DH; Lee-CC; Lee-C - CEMENT-AND-CONCRETE-RESEARCH. NOV 2003; 33 (11) : 1749-1754. Sewage sludge ash (SSA) is a recycled material and can be used in cement mortar as pozzolan. To improve the mortar properties, this research utilized mechanical grinding to adjust the fineness of SSA. Finely ground SSA with Blaine fineness of 500-1000 m(2)/kg was added to mortar to replace 20% of portland cement. The initial and final setting times of SSA-cement paste simultaneously prolonged when SSA fineness increased. Because of the lubricant effect and morphology improvement, the workability of SSA mortar increased when fineness increased. In addition, the pozzolanic activity of SSA and the compressive strength of mortar increased when SSA fineness did. The strength activity index (SAI) value approximately increased 5% when SSA fineness increased per 100 m(2)/kg. According to the results, the application of mechanical grinding to adjust SSA fineness was an effective modification to improve SSA mortar properties including workability and compressive strength. [16] SYNTHESIS OF TITE2 NANOTUBES Li-SL; Tao-ZL; Gao-F; Chen-J - ACTA-CHIMICA-SINICA. MAR 28 2004; 62 (6) : 634-636. TiTe2 is generated by solid thermal reaction of Te powder and ball-milled Ti powder. The structural and morphological features of the as-synthesized product have been thoroughly characterized by XRD, SEM, TEM and HRTEM. The results

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show that the present route provides an easy access to large-scale preparation of high purity TiTe2 nanotubes. By comparing the as-synthesized samples, we can discover that ball-milling treatment is necessary to the formation of nanotubes owing to its effect on the dimension of reactant particles. [15] STUDIES ON HIGH-PERFORMANCE BLENDED/MULTIBLENDED CEMENTS AND THEIR DURABILITY CHARACTERISTICS Pandey-SP; Singh-AK; Sharma-RL; Tiwari-AK - CEMENT-AND-CONCRETE-RESEARCH. SEP 2003; 33 (9) : 1433-1436. Number of blends were prepared by intergrinding clinker, gypsum, fly ash, calcined clay, microsilica and limestone in laboratory ball mill in varying percentages, and their physical properties such as fineness, consistency, setting time and compressive strength have been determined. The durability tests on selected compositions were also conducted by exposing the mortar cubes separately in 5% Na2SO4 and 5% NaCl solutions till the age of 90 and 180 days. The performance was observed by compressive strength development criteria after various length of exposure. Results have been discussed and found that the durability of blended cement is higher than the ordinary Portland cement. [14] PREPARATION AND PRELIMINARY CERTIFICATION OF TWO NEW POLISH CRMS FOR INORGANIC TRACE ANALYSIS Dybczynski-R; Danko-B; Kulisa-K; Maleszewska-E; Polkowska-Motrenko-H; Samczynski-Z; Szopa-Z - JOURNAL-OF-RADIOANALYTICAL-AND-NUCLEAR-CHEMISTRY. 2004; 259 (3) : 409-413. Preparation and characterization of two new reference materials of biological origin, namely: Tea Leaves (INCT-TL-1) and Mixed Polish Herbs (INCT-MPH-2) is described. The raw materials were ground in an agate ball mill, sieved through a nylon sieve, collecting fraction of particle size: empty set less than or equal to 67 mum, and carefully homogenized. Preliminary homogeneity testing by XRF method and final checking of homogeneity by NAA after distribution of the materials into containers revealed that they are sufficiently homogeneous at least for sample size greater than or equal to100 mg. Both materials were prepared in amounts exceeding 40 kg and certified on the basis of a worldwide interlaboratory comparison, in which 109 laboratories from 19 countries participated. The method of data evaluation leading to assignment of certified values was essentially the same as that used previously in this Laboratory, but supplemented by additional data from the analysis of a CRM which was sent to the participants and analyzed by them along with the candidate reference materials. In addition the results for a few elements developed by very accurate methods in this Laboratory were obtained and used to support the certification process. Analytical and stability uncertainties were quantified to arrive at combined uncertainties of the certified values. So far 18 elements in INCT-TL-1 and 21 in INCT-MPH-2 could be certified. [13] CHARACTERIZATION OF NI57ZR20TI18AL5 AMORPHOUS POWDER OBTAINED BY MECHANICAL ALLOYING Lee-PY; Lin-CK; Jeng-IK; Wang-CC; Chen-GS - MATERIALS-CHEMISTRY-AND-PHYSICS. APR 2004; 84 (2-3) : 358-362. This study examined the amorphization behavior and thermal stability of mechanically alloyed Ni57Zr20Ti18Al5 alloy powders synthesized by high-energy ball milling. Complete amorphization is feasible after 5h of milling. The thermal stability of the Ni57Zr20Ti18Al5 amorphous powders was investigated by differential thermal analysis. As the results demonstrated, the temperature interval of the supercooled liquid region defined by the difference between glass transition temperature (T-g) and crystallization temperature (T-x), i.e., DeltaT (=T-x - T-g) is 54 K for Ni57Zr20Ti18Al5. The glass transition and crystallization temperatures of mechanically alloyed samples are different from those reported in the literature for samples prepared by melt spinning techniques. The different thermal stability is believed to be due to the introduction of impurities into the ball-milled samples during mechanical alloying process. The glass transition behavior in the Ni57Zr20Ti18Al5 is found to be a kinetically modified thermodynamic phase transformation process. [12] CHARACTERIZATION OF CRYSTALLINE STRUCTURE OF BALL-MILLED NANO-NI-ZN-FERRITE BY RIETVELD METHOD Bid-S; Pradhan-SK - MATERIALS-CHEMISTRY-AND-PHYSICS. APR 2004; 84 (2-3) : 291-301. Nanocrystalline Ni-Zn-ferrite is synthesized at room temperature by high-energy ball milling with the target composition 0.5 ZnO, 0.5 NiO and 1.0alpha-Fe2O3 ((0.5 + 0.5):1 mole fraction). The formation of non-stoichiometric ferrite phase is noticed after 1 h of ball milling and its content increases with increasing milling time. The structural and microstructural evolution of nickel-zinc-ferrite caused by milling is investigated by X-ray powder diffraction. The relative phase abundances of different phases, particle size, r.m.s. (root mean square) strain, lattice parameter change, etc. have been estimated from Rietveld's powder structure refinement analysis of XRD data. It is revealed from the XRD pattern that ZnO reflections are completely disappeared within 1 h of milling but a significant amount (similar to7 wt.%) of nanocrystalline NiO and alpha-Fe2O3 (similar to12 wt.%) remain excess even after 11 h of milling. It indicates that during ball milling a non-stoichiometric mixture of NiO, ZnO and alpha-Fe2O3 may lead to the formation of non-stoichiometric Ni-Zn-ferrite. A considerable amount of ferrite is formed within 11 h of ball milling with lattice parameter higher than that of stoichiometric Ni-Zn-ferrite prepared by conventional ceramic route keeping the same powder mixture at 1473 K for 2 h. The 11 h milled sample is post-annealed at 773 K for different durations to verify the solubility of both the residual parts of NiO and alpha-Fe2O3 in forming the target composition. The post-annealing treatment reveals that within 1 h of post-annealing, stoichiometric Ni-Zn-ferrite is formed and nanocrystalline ferrite particles become almost strain-free within 15 h of post-annealing time.

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[11] A LIBERATION MODEL FOR COMMINUTION BASED ON PROBABILITY THEORY Gay-SL - MINERALS-ENGINEERING. APR 2004; 17 (4) : 525-534. Mineral processing plants use two main processes; these are comminution and separation. The objective of the comminution process is to break complex particles consisting of numerous minerals into smaller simpler particles where individual particles consist primarily of only one mineral. The process in which the mineral composition distribution in particles changes due to breakage is called 'liberation'. The purpose of separation is to separate particles consisting of valuable mineral from those containing nonvaluable mineral. The energy required to break particles to fine sizes is expensive, and therefore the mineral processing engineer must design the circuit so that the breakage of liberated particles is reduced in favour of breaking composite particles. In order to effectively optimize a circuit through simulation it is necessary to predict how the mineral composition distributions change due to comminution. Such a model is called a 'liberation model for comminution'. It was generally considered that such a model should incorporate information about the ore, such as the texture. However, the relationship between the feed and product particles can be estimated using a probability method, with the probability being defined as the probability that a feed particle of a particular composition and size will form a particular product particle of a particular size and composition. The model is based on maximizing the entropy of the probability subject to mass constraints and composition constraint. Not only does this methodology allow a liberation model to be developed for binary particles, but also for particles consisting of many minerals. Results from applying the model to real plant ore are presented. A laboratory ball mill was used to break particles. The results from this experiment were used to estimate the kernel which represents the relationship between parent and progeny particles. A second feed, consisting primarily of heavy particles subsampled from the main ore was then ground through the same mill. The results from the first experiment were used to predict the product of the second experiment. The agreement between the predicted results and the actual results are very good. It is therefore recommended that more extensive validation is needed to fully evaluate the substance of the method. [10] CHARACTERISTICS OF OPEN- AND CLOSED-CIRCUIT GRINDING SYSTEMS Kobayashi-A; Nagasaka-H; Iizuka-K; Yoshida-H - SEPARATION-AND-PURIFICATION-TECHNOLOGY. APR 15 2004; 36 (2) : 157-165. The characteristic differences between open- and closed-circuit grinding systems were examined via the use of a continuous vibration ball mill and a blade type classifier. For the same median diameter of the product, the rate of powder production in the closed-circuit is about 5% higher than that of the open-circuit. The median diameter of classified coarse particles for the closed-circuit is smaller than that for the open-circuit. The power requirement per unit mass production increases with decreasing mean diameter of the product. For the same mean diameter of the product, the power requirement for the closed-circuit process is about 5% smaller than that of the open-circuit process. This value corresponds to the difference in the rate of powder production between the two systems. [9] INTERMETALLIC PHASE STABILITY ON HIGH ENERGY TREATMENTS (RAPID QUENCHING, ION IRRADIATION AND MECHANICAL MILLING) Diakonova-NP; Sviridova-TA; Semina-VK; Skakov-YA - JOURNAL-OF-ALLOYS-AND-COMPOUNDS. MAR 24 2004; 367 (1-2) : 199-204. The stability of transition metal intermetallics belonging to the Frank-Kasper (FK) phase family and to the spherically close-packed (SCP) phases subjected to rapid quenching (RQ), ion irradiation (II) and mechanical milling (MM) has been studied. It was found that the transition into the amorphous state (AS) is independent of the treatment and only depends on the crystal structure. The phases with the least stability on all treatments studied here are the Frank-Kasper type intermetallics. The phases that are amorphized most readily are those in which the fraction of atoms with icosahedral coordination (IC) exceeds 1/3 and the short-range order (SRO) in the crystalline compound is similar to that of the amorphous phase (AP). Amorphization in SCP-based intermetallics is hampered; it becomes easier on increasing the atomic size difference. The treatment technologies studied here may be ranged from "hard" to "soft" in the following order: MM --> II --> RQ [8] ON THE SYNTHESIS OF ZR-BASED BULK AMORPHOUS ALLOYS FROM GLASS-FORMING COMPOUNDS AND ELEMENTAL POWDERS Djakonova-NP; Sviridova-TA; Zakharova-EA; Molokanov-VV; Petrzhik-MI - JOURNAL-OF-ALLOYS-AND-COMPOUNDS. MAR 24 2004; 367 (1-2) : 191-198. The possibility of producing Zr-based bulk amorphous alloys (Zr65Cu17.5Ni10Al7.5 and Zr57Ti5Cu20Ni8Al10) by mechanical alloying (MA) from either a mixture of elemental powders (EP), or a mixture of glass-forming compounds (GFC), has been investigated. A preliminary study of the crystal structure stability of the GFC-ingredients during mechanical milling was performed. Amorphization was found to be significantly enhanced during MA by using a GFC mixture. A considerable difference in the phase transformations observed on heating the amorphous phase (AP) was noted for alloys obtained from GFC, as compared with those produced by melt quenching (MQ) or milling of a mixture of elemental powders. It is shown that the amorphous phase obtained by MA from GFC has a wider undercooled liquid region between the glass transition temperature T-g and the crystallization temperature T-x than the amorphous phase produced by the conventional MQ technique. [7] THE MECHANICAL MILLING OF AL/TIO2 COMPOSITE POWDERS

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Zhang-DL; Cai-ZH; Adam-G - JOM-. FEB 2004; 56 (2) : 53-56. The processing of Al/TiO2 composite powders produced by high-energy mechanical milling leads to production of a range of valuable, titanium-based materials. They include Ti(Al,O)/Al2O3 and TixAly (O)/Al2O3 composite powders, bulk composites and Ti3Al/TiAl alloy powders, and corresponding bulk materials. The strength of the Ti(Al,O)/ Al2O3 and TixAly(O)/Al2O3 composites is moderate, but their high-temperature oxidation resistance is exceptionally high, making the titanium-based composite powders favorable feedstock materials for protective coatings. The hardness of the Ti(Al,O)/Al2O3 and Ti3Al(O)/Al2O3 composites is also very high (10-16 GPa [6] PLZT CERAMICS FROM MECHANICALLY ALLOYED POWDER AND THEIR ANOMALOUS PHOTOVOLTAIC EFFECT Li-JF; Tatagi-K; Zhang-BP - JOURNAL-OF-MATERIALS-SCIENCE. APR 15 2004; 39 (8) : 2879-2882. [5] RAMAN SPECTROSCOPY MEASUREMENTS OF HYDROXYAPATITE OBTAINED BY MECHANICAL ALLOYING Silva-CC; Sombra-ASB - JOURNAL-OF-PHYSICS-AND-CHEMISTRY-OF-SOLIDS. MAY 2004; 65 (5) : 1031-1033. [4] CHARACTERIZATION OF NI57ZR20TI18AL5 AMORPHOUS POWDER OBTAINED BY MECHANICAL ALLOYING Lee-PY; Lin-CK; Jeng-IK; Wang-CC; Chen-GS - MATERIALS-CHEMISTRY-AND-PHYSICS. APR 2004; 84 (2-3) : 358-362. This study examined the amorphization behavior and thermal stability of mechanically alloyed Ni57Zr20Ti18Al5 alloy powders synthesized by high-energy ball milling. Complete amorphization is feasible after 5h of milling. The thermal stability of the Ni57Zr20Ti18Al5 amorphous powders was investigated by differential thermal analysis. As the results demonstrated, the temperature interval of the supercooled liquid region defined by the difference between glass transition temperature (T-g) and crystallization temperature (T-x), i.e., DeltaT (=T-x - T-g) is 54 K for Ni57Zr20Ti18Al5. The glass transition and crystallization temperatures of mechanically alloyed samples are different from those reported in the literature for samples prepared by melt spinning techniques. The different thermal stability is believed to be due to the introduction of impurities into the ball-milled samples during mechanical alloying process. The glass transition behavior in the Ni57Zr20Ti18Al5 is found to be a kinetically modified thermodynamic phase transformation process. [3] THE EFFECT OF ZRO2 GRINDING MEDIA ON THE ATTRITION MILLING OF FEAL WITH Y2O3 Gedevanishvili-S; Deevi-SC - MATERIALS-SCIENCE-AND-ENGINEERING-A-STRUCTURAL-MATERIALS-PROPERTIES-MICROSTRUCTURE-AND-PROCESSING. MAR 25 2004; 369 (1-2) : 236-240. Attrition milling of water and gas atomized FeAl was carried out with Y2O3, where ZrO2 was used as a grinding media in place of stainless steel balls to avoid contamination with Cr and C. Consolidation of the milled powders produced complex FeAl phases containing Zr which doubled the hardness and significantly improved the creep resistance as compared to that of unmilled and consolidated FeAl. [2] ELECTROCHEMICAL BEHAVIOR OF NANOCRYSTALLINE IRON ALUMINIDE OBTAINED BY MECHANICALLY ACTIVATED FIELD ACTIVATED PRESSURE ASSISTED SYNTHESIS El-Kedim-O; Paris-S; Phigini-C; Bernard-F; Gaffet-E; Munir-ZA - MATERIALS-SCIENCE-AND-ENGINEERING-A-STRUCTURAL-MATERIALS-PROPERTIES-MICROSTRUCTURE-AND-PROCESSING. MAR 25 2004; 369 (1-2):49-55. The corrosion behavior of nanocrystalline iron aluminide obtained by mechanically activated field-activated pressure-assisted synthesis was investigated in sulphuric acid media using potentiodynamic curves. The effect of microstructure on the electrochemical corrosion resistance was investigated by examining samples which were heat treated to effect a change in crystallite size and microdistorsion. [1] INITIAL STAGE OF MECHANICAL ALLOYING IN THE FE-C SYSTEM Yelsukov-EP; Dorofeev-GA; Zagainov-AV; Vildanova-NF; Maratkanova-AN - MATERIALS-SCIENCE-AND-ENGINEERING-A-STRUCTURAL-MATERIALS-PROPERTIES-MICROSTRUCTURE-AND-PROCESSING. MAR 25 2004; 369 (1-2) : 16-22. Mossbauer spectroscopy (MS), X-ray diffraction, transmission electron microscopy (TEM), Auger spectroscopy, magnetic measurements and differential thermal analysis (DTA) were used to study the initial stages of mechanical alloying in the Fe-C system. The mechanical alloying of Fe and C powder mixtures with the atomic ratio 85:15 in a planetary ball mill was taken as an example. It has been shown that the initial stage involves the formation of nanostructure in the alpha-Fe particles, penetration and segregation of carbon along the alpha-Fe grain boundaries, formation of the amorphous Fe-C phase in the interface regions consisting of the boundary and close-to-boundary distorted zone. The carbon concentration in the amorphous Fe-C phase is estimated at 25 at.%. The amount of the amorphous phase reaches 67 at.% (67% of all the Fe and C atoms are in this phase).

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Lettre Mensuelle N°111 - Réseau Français de Mécanosynthèse - Juin 2004 - Monthly Newsletter from French Mechanosynthesis Network - N°111 - June 2004