A molecular dynamics investigation into the ballistic impact resistance of CrFeCoNi crystalline-amorphous high-entropy nanocomposites

Crystalline-amorphous (C-A) high-entropy nanocomposites with core-shell nanostructures have been demonstrated excellent mechanical properties at high strain rates due to their cooperative strengthening mechanism, which has great potential in the field of anti-ballistic impact. Nevertheless, limited research has been performed on the ballistic impact performance of C-A high-entropy nanocomposites, and their underlying ballistic impact resistance mechanism remains unclear. Herein, molecular dynamics (MD) simulations were conducted to investigate the dynamic response of CrFeCoNi C-A high-entropy nanocomposites subjected to ballistic impact. The effect of amorphous thickness on the deformation mechanisms of these nanocomposites was considered. The results revealed that an optimal amorphous thickness which could trigger a cooperative strengthening mechanism between dislocations and shear transformation zones (STZs) and minimize the penetration depth existed in the nanocomposites under various impact velocities. This work could provide valuable guidance for the optimization of C-A high-entropy nanocomposites with superior penetration resistance.