The typical manners of dynamic crack propagation along the metal/ceramics interfaces: A molecular dynamics study (1404.4198v1)

Abstract: This letter addresses the issue of interfacial crack propagation mechanisms on various interfaces with using molecular dynamics. Four different interfacial crack propagation manners are recognized by MD simulations: 1, the crack propagates along the interface strictly; 2, the nucleation of a twinning at the crack tip leads to the crack tip blunting; 3, the daughter crack appears ahead of the main crack and then coalesces to the mother crack; 4, the crack tip blunts with stacking fault nucleation at the crack tip. Furthermore, the adhesive strength coefficient {\lambda}is used to identify the type of the interface. Interface with {\lambda}> 0.9 means an ordered interface, and interfacial crack propagates in mode I or mode II. While {\lambda}< 0.9 represents a disordered interface, and mode III and mode IV of the interfacial cracks are preferred. This work illustrates the effect of adhesive strength of interface on the mechanism of crack propagation along the interface of metal/ceramics nano-composites.