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DOE OSTI · 1993216

Overdriven Shocks: Recapturing a Lost Capability

Abstract

Wallace’s theory for overdriven shocks in solids provides a theoretical framework for the strength of materials in the strong shock regime at strain rates unobtainable by current experimental means. Using irreversible thermodynamics, this theory incorporates heat and plastic flow as dissipative mechanisms under shock conditions allowing for the calculation of properties such as deviatoric stresses, plastic strains, and plastic strain rates. Though the theory is over four decades old, it has been used to calculate the strength behavior of only a small handful of metals. In this work, we have recaptured the ability to conduct this analysis, and two crucial aspects of the overdriven theory will be discussed: 1) the modeling assumptions that comprise this theoretical approach and 2) what information is needed to calculate the strength behavior for new materials.

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Allen, Jason Paul, Hickmann, Kyle Scott, Andrews, Stephen Arthur. 2023-08-01. Overdriven Shocks: Recapturing a Lost Capability. https://doi.org/10.2172/1993216

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36 MATERIALS SCIENCE↗