Effects of Toughness Mismatch on Failure Behavior of Bi-Material Interfaces

The effects of toughness mismatch on failure behavior of bi-material interfaces have been investigated by FEM numerical analyses based on GTN damage mechanics model. The results show that the effects of toughness mismatch on fracture resistance and crack growth path are related to strength mismatch, and the interaction between them determines failure behavior of the interfaces. For the interface cracks with higher strength mismatch and lower toughness mismatch, the fracture resistance behavior are mainly controlled by strength mismatch. While for the interface cracks with lower strength mismatch and higher toughness mismatch, the failure behavior are dominated by toughness mismatch.