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(III-nitrides). Finally, the groups studying heterogeneous metamorphic electronics will be looking at graphene based electronics, heterogeneous systems for tetrahertz electronics, and thermal transport in heterogeneous systems. Q. What are the five-year goals for MSME? A. They are structured very similarly to the MEDE goals. Two-year goals: Science: Advance the fundamental understanding and implementation of physics-based modeling of electronic materials Scale or technical core element Atomic Crystal Mesoscale Macroscale Electronic structure, thermal motion of nuclei, bond rupture Cleavage, amorphization, dislocation motion, stacking fault nucleation, cracking Triple-junction crack nucleation, grainboundary defect-activated cracks, intergranular vs. transgranular fracture, crack interactions, elastic effects on residual stresses and cracking Fast crack growth, effective plasticity, anisotropic damage growth, short vs. long cracks, texture, fragmentation Generally identified, understood or implemented Table 1. The technical core elements necessary for designing materials are not well identified or understood for boron carbide, regardless of length scale. This table summarizes the MEDE consortium view of relevant mechanisms, techniques, models, or phenomena for each core area for each length scale. across time and space to develop a set of algorithms and theories for a broad range of electronic materials to create new or improved electronic devices, and advance the understanding of existing performance. Benefit to the soldier: Resulting models and algorithms will enable the Primary mechanism advancement of sensors and power and energy devices on the battlefield. Five-year goals: Science: Integrate new multidisciplinary/ multiscale physics to enable multiscale modeling and simulation capability that is validated experimentally in time and space to a priori design new or improved electronic materials that are uniquely characterized, synthesized, and processed. Benefit to the soldier: Resulting models and algorithms will enable the development of new sensors and power and energy devices on the battlefield. The CRA will transition to ARL the key materials characteristics State-of-the-Art for Ceramics (Boron Carbide) Advanced experimental technique Modeling & simulation Spectroscopy, shock Hugoniot HREM, TEM, dynamic TEM, Kolsky bar, microcompression, nanoindentation, DAC HREM, TEM, dynamic TEM, Kolsky bar, X-ray microdiffration, instrumented indentation, phase contrast, in-situ microcompression for GB strength, acoustic spectroscopy Shock expts, Kolsky bar, spall experiments, in situ visualization of damage Quantum mechanics, density functional theory, energy of states Molecular dynamics, discrete dislocation dynamics, discrete twinning dynamics, crystal plasticity Crystal plasticity, gradient terms, microstructureresolved finite- element method and optimal transportation meshfree Viscoplasticity, FEM OTM, uncertainty quantification Weak indentification understanding, or implementation Sometimes identified, some understanding, some implementation and properties to achieve Bridging the scales twinning, twin-induced failure, anisotropic Coarse-grained DFT, potentials Coarse-grained DFT, hot QC, hyperdynamics Defect dynamics, models Enhanced continua, models, defect dynamics power and energy devices with twice the energy density and 10–15 percent more lifetime, and sensors that are 10–15 percent more efficient. Ten-year goals: Science: Advance the state of the art in multiscale modeling and electronic materials to create a capability for “Materials Optimization and Materials by Design.” Benefit to the soldier: The CRA and ARL will exercise “materials by design” capability to design new sensors and power and energy devices for the battlefield that treble the energy density, 30 percent longer lifetimes, and are 20–30 percent more efficient at a lower cost. Q. Regarding boron carbide and S-glass/ epoxy composite, are there broader impacts beyond Army interests for this work? A. Success in this program will, I believe, catalyze work across the materials Material characterization & properties Synthesis & processing probablistic nonlocal Moduli, bandgap Anisotropic moduli, cleavage and twinning planes, intrinsic toughness Grain size distribution, grain morphology, texture, damage characterization High-strain-rate and high-pressure response, nonproportional loading, damage characterization Chemistry Powder production and control Grain size control, grain boundary control microstructural design, advanced processing tehniques Sintering, hot-pressing, advanced processing techniques Poorly identified, poorly understood, or early implementation Not identified, not understood or not implemented science and engineering communities for many other applications. Basically, it will provide a multiscale computational tool box that will be applicable to many other material systems. For more information about the Enterprise and its CRAs visit www.arl. army.mil/www/default.cfm?page=532. References 1National Research Council, “Opportunities in Protection Materials Science and Technology for Future Army Applications,” The National Academies Press (2011). 2National Research Council, “Integrated Computational Systems Engineering: A Transformational Discipline for Improved Competitiveness and National Security”, The National Academies Press, 2008. 3M.F. Ashby, Materials Selection in Mechanical Design. Pergamon, Tarrytown, N.Y., (1992). 4 G.B. Olson, “Computational Design of Hierarchically Structured Materials,” Science, 277, 1237—42 (1997). n American Ceramic Society Bulletin, Vol. 92, No. 2 | www.ceramics.org 31 (Credit: MEDE CRA.)


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