THE EFFECT OF FLAWS ON THE PROPAGATION OF CRACKS AT BI-MATERIALS INTERFACES

This study uses the boundary element method to investigate the effects of interfacial flaws on the propagation of a crack at or near an inte rface between two elastic, isotropic materials. These calculations rev eal that flaws tend to deflect cracks approaching the interface from t heir original trajectory if the distance between the flaw and crack ti p is small in relation to the flaw size. It is found that the higher t he elastic mismatch parameter, the more crack trajectories are attract ed to flaws. Other calculations show that materials with interfacial f laws have a significantly increased tendency to deflect cracks along t he interface as compared to defect-free materials.