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Presentation for Nano and Microscale Behavior of Materials course. Illustrates the methods that engineers are using in researching and developing the newest materials in the defense industry.
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Current Frontier in Ceramic Armor
John WaldronMechanical Engineering, Villanova
University
Why ceramics in armor? Materials used in ceramic armor
◦ Al2O3, B4C, SiC Current Applications
Use of Ceramics in Armor
IBD-Deisenroth Engineering
Ballistic Impact
N.V. David, et al September 2009
Relevant Material Properties
P.G. Karandilar, et. Al 2008
Numerical/Computational Research Ballistics Research Biomimetic Research Comparisons Future Work
Current Research
Dynamics of Ballistic Protection◦ Formations of cracks
and damage zones◦ Changes in
microstructure◦ Phase Transformations
Predicative Methods ◦ Creating New
Algorithms [Fernandez]
◦ Using Established Damage Methods [Feli]
Numerical Methods
Boron Carbide Fracture Zone
P.G. Karandilar, 2008
Johnson-Holmquist Model Prevailing Damage Model
Large Deformation and Damage Evolution
Contains Material Constants
Intact Material Strength: 𝜎𝑖∗= 𝜎𝐻𝐸𝐿𝐴(𝑃∗+ 𝑇∗)𝑁 (1+ 𝐶ln𝜀ሶ) Fractured Material Strength: 𝜎𝑓∗= 𝜎𝐻𝐸𝐿𝐵(𝑃∗)𝑁 (1+ 𝐶ln𝜀ሶ) Current Material Strength: 𝜎∗= 𝜎𝑖∗− 𝐷(𝜎𝑖∗− 𝜎𝑓∗)
Damage Increment: 𝐷= σ △𝜀𝑝𝜀𝑓+ 1 3ൗ�𝐺(𝜎𝑖∗− 𝜎𝑓∗) Feli, 2011
Numerical Simulation
Fernandez, 2011 Feli, 2011
Tests Current Materials Involves Projectiles Currently Used in Combat Can Determine Applications of Certain Ceramic
Armors [Medvedovski]
Ballistics Performance Research
Medvedovski, 2010
Medvedovski, 2010
Dinosaur Eel [polypterus senegalus]
Composite Layers Exclusive Deformation
Mechanisms
Biomimetic Research
Bruet, B. J. F et al 2008
Numerical Method: Most Precise
Ballistics Performance Method: Most Practical
Biomimetic Research: Alternative Solutions
Future Work: Tailoring Microstructure
Comparisons
Bruet, B. J. F et al 2008, “Materials Design Principles of Ancient Fish Armour,” Nature Materials, Volume 7, pp. 748–756.
D. Fernandez-Fdz, R. Zaera, J. Fernandez-Saez, “A constitutive equation for ceramic materials used in lightweight armors.” Computers and Structures Volume 89, 2011 2316-2324
Eugene Medvedovski, “Ballistic performance of armour ceramics: Influence of design and structure. Part 1.” Ceramics International Volume 36, 2010. 2103-2115
References
IBD Deisenroth Engineering, “Breakthrough in Material Development for Ballistic Protection” February 16, 2011http://www.ibd-deisenroth-engineering.de/news.html
N.V. David, et al “Ballistic Resistant Body Armor: Contemporary and Prospective Materials and Related Protection Mechanisms.” Applied Mechanics Reviews Volume 62. September 2009
P.G. Karandilar, et. al “A Review of Ceramics for Armor Applications” Advances in Ceramic Armor IV Ceramic Engineering and Science Proceedings Volume 29, Issue 6, 2008 163-173
S. Feli, M.R. Asgari, “Finite Element Simulation of ceramic/composite armor under ballistic impact” Composites: Part B Volume 42, 2011 771-780
References