Designer materials for a secure future

Materials for armor applications are increasingly being required to be strong and light-weight as a consequence of increasing threat levels. We focus on materials response subjected to impact loads, understanding deformation and failure mechanisms, and developing validated mechanism-based models capable of predicting materials response under high rate loading conditions. As a specific example, we will examine the dynamic behavior of nanocrystalline aluminum using atomistic simulations. The dynamic behavior of this material is discussed in terms of competing deformation mechanisms--slip and twinning. Insights from high strain rate atomistic simulations were used in developing a fundamental mechanism-based analytical model to assist in the microstructural design of advanced materials to tailor their macroscopic properties.

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