The Effect of an Elliptic Hole on the Elastic Interaction between Screw Dislocations and a Macrocrack

Abstract

AbstractThe effect of an elliptic hole on the elastic interaction between a screw dislocation and a macrocrack is investigated by the conformal mapping technique. The stress field, the stress intensity factor at the crack tip, and the force on the dislocation are derived. Both the stress intensity factor at the crack tip and the force on the dislocation are strongly influenced by the elliptic hole, and are dependent on the positions of the lattice screw dislocation, the dislocations in the elliptic hole, and the geometry of the elliptic hole. If the lattice dislocation arises from the macrocrack or infinity, the lattice dislocation always has a shielding effect on the propagation of the crack. It is also found that an elliptic hole with a smaller minor semi‐axis b will induce a larger magnitude of the negative stress intensity factor at the crack tip, so it has a larger shielding effect on the crack propagation. Finally, several special cases of the results are also discussed.