Molecular Dynamics Simulation of High-Speed Impact on Titanium Alloy Target Surfaces by Conical Tungsten Fragments

Molecular dynamics (MD) simulations with embedded atom method (EAM) potential are performed to precisely resolve the picosecond transient evolution of impact responses. Those obtained results show that after high-speed tungsten fragments impinge on titanium plates, part of the fragments disperse within the impact crater, whereas the rest propagate radially and splash rearward. Non-penetrating conical tungsten fragments lead to obvious bulging deformation on the target back surface. Three pathways of kinetic energy transfer are identified: energy transfer to titanium atoms to induce target damage, backward recoil accompanied by fragment clouds, and continuous penetration and in-situ embedding into the substrate. Crater expansion is synergistically dominated by fragment compression and kinetic energy delivery from fragment clouds. Increased impact kinetic energy facilitates the formation of penetrating Ti-W mixed atomic clusters. Elevated substrate temperature aggravates atomic thermal vibration and weakens interatomic bonding, which further increases crater diameter and depth. This study complements the theoretical framework of fragment-induced damage and provides fundamental theoretical support for improving the destructive performance of fragmentation warheads.