Intergranular Hotspots: A Molecular Dynamics Study on the Influence of Compressive and Shear Work

Numerous crystal- and microstructural-level mechanisms are at play in the formation of hotspots, which known to govern high explosives initiation behavior. Most these mechanisms, including pore collapse, interfacial friction, shear banding, involve both compressive work done within material have thus far remained difficult separate. We assess hotspots formed shocked crystal–crystal interfaces using quasi-1D molecular dynamics simulations that isolate effects due compression shear. Two explosive materials considered (TATB PETN) exhibit distinctly different levels conformational flexibility crystal packing anisotropy. Temperature intramolecular strain energy localization hotspot assessed through parametric variation orientation two velocity components respectively modulate work. The resulting found be highly localized a region 5–20 nm interface. Compressive plays considerably larger role localizing temperature for all orientations considered. Shear induces moderate increase relative unsheared cases only relatively weak shock pressures approximately 10 GPa. These results help rank importance generation anticipated guide treatment coarse-grained models polycrystalline high-explosive materials.