Impact response and chemical reaction mechanisms of CL-20/TNT co-crystals with elliptical voids defects: A study of molecular dynamics

The presence of defects in energetic materials significantly affects their performance, making it essential to investigate their impact response to ensure safety and reliability. Existing studies primarily focus on defect-free energetic materials, with limited research examining the influence of various defects on their impact performance. This study examines the initial response and chemical reaction mechanisms of CL-20/TNT co-crystals with elliptical void defects under impact conditions, utilizing molecular dynamics simulations and reactive force field techniques. The findings indicate that void defects in CL-20/TNT co-crystals create hot spots upon impact, which significantly affect the decomposition of molecules surrounding the defects. Larger voids lead to increased average temperatures and enlarge hot spot regions, thereby accelerating the decomposition of CL-20/TNT co-crystals and promoting the nitro group detachment in CL-20, while concurrently inhibiting its polymerization and adsorption. Furthermore, an increase in the void aspect ratio elevates peak shear stress. Notably, increasing the number of voids is more effective at reducing the quantity of co-crystals than merely augmenting the aspect ratio. Overall, this study provides a comprehensive elucidation of the impact mechanisms associated with elliptical void defects in the shock response of CL-20/TNT co-crystals.