Configuration effect on coalescence of voids in single-crystal copper under shock loading

Void coalescence is one of the most critical stages leading to dynamic ductile fracture. In this paper, the effect of configuration on coalescence in single-crystal copper has been investigated using a molecular dynamics simulation. The configuration represented by φ which defines the angle between the line connecting the centers of two voids and shock direction. The results show that the 60° configuration coalesced most easily. Microscopic analysis revealed that the anisotropic emission patterns of shear dislocation loops around the voids during the compressive stage weaken the local structure between two voids and have a significant influence on coalescence during the tensile stage. An analytical model based on anisotropic dislocation emission has been derived, and it explains the coalescence phenomena very well.