Interfacial crack kinking subjected to contact effects

We investigate the problem of a kinking crack at a bimaterial interface when the two surfaces are in contact near the crack tip.Using a potential function and the dislocation technique, we relate, by a singular integral equation, the stress intensity factors (SIF) at the kinking crack tip to the SIF before crack kinking.We use Gauss-Chebyshev integration formulas to solve this integral equation numerically.We evaluate the kinking angles from a bimaterial interface under conditions of contact using the maximum energy release rate criterion and compare these angles with our experiments and those in the literature.The interfacial crack is demonstrated by simulation and experiments to kink into the more compliant material at an angle of about 80 • .