The elastic interaction between a screw dislocation and a micro-crack near to an elliptical hole was investigated. The stress field, the stress intensity factors at each tip of the micro-crack, and the image force on the lattice dislocation were derived. The latter 2 quantities were both strongly affected by the elliptical hole, and depended upon the positions of the lattice screw dislocation, the dislocations which existed in the micro-crack and elliptical hole, and the geometry of the latter. If a lattice dislocation originated from the right-hand tip of the micro-crack under a mode-III applied stress, the lattice dislocation had a shielding effect upon the propagation of the right-hand crack tip but enhanced the movement of the left-hand crack tip. It was also found that the dislocations which existed in the elliptical hole and the micro-crack played an important role in fracture.

Elastic Interaction between Screw Dislocations and a Micro-Crack near to an Elliptical Hole. S.Shamtsong: Materials Chemistry and Physics, 1997, 48[3], 220-6