Contact zone in an interfacial Zener-Stroh crack

A Zener-Stroh crack is formed by a dislocation pileup and therefore is a net dislocation loaded crack. Due to its displacement loading approach, only one of the two crack tips is sharp and crack propagation is possible along the sharp tip only. When a Zener-Stroh crack is initiated along an interface, this sharp crack tip may be closed due to material mismatch and loading combination. In the present paper, an interfacial Zener-Stroh crack is analyzed with the consideration of a crack tip contact zone. It is found that the contact zone size which depends on the ratio of gliding dislocation and climbing dislocation can be fairly large even when the loading is not "shear" dominant. (C) 1998 Elsevier Science Ltd. All rights reserved.