Fracture Model for an Interface Crack with Bridged Zone

摘要

The application of two-parametric fracture criterion to the problem of cracks limit equilibrium in homogeneous media or at an interface of two different materials is considered. The necessary condition of the crack tip limit equilibrium is the equality of the energy release rate and the rate of the energy dissipation by the bonds (the first condition of fracture). The second condition of fracture is the condition of the bond limit stretching at the trailing edge of the bridge zone. Based on these two fracture conditions the regimes of the bridged zone and the crack tip equilibrium and growth are considered. The estimations of the equilibrium size of the bridged zone, the adhesion fracture energy and the critical stress (the interface strength) depend on the crack size are found.