A novel Eulerian-based computational framework for modeling single-crystal plasticity in shock-induced void collapse in heterogeneous energetic materials*

This presentation will demonstrate a novel Eulerian framework for modeling crystal plasticity in shock-loaded energetic materials. The specific focus will be to address challenges in Eulerian crystal plasticity and demonstrate a robust computational framework for large anisotropic plastic deformations in single-crystal β-HMX. Plastic-strain localization and associated heating around microstructural defects (voids, cracks etc.) in shock-loaded crystalline energetic materials are well-known to initiate exothermic reactions. Accurate initiation modeling demands frameworks which can handle extreme deformations as well as anisotropic plastic localizations in materials. While Eulerian formulations are naturally suited for large deformations, plasticity is typically modeled via isotropic J-2 models, which do not reflect the roles of preferential slip directions in plastic deformations. This presentation will demonstrate an Eulerian anisotropic plasticity framework with the example of void-collapse in HMX. Computations will be performed for different shock strengths and crystal orientations to demonstrate the roles of preferential directions during void-collapse.