Atomistic simulations of dislocation - crack interaction

The interaction of dislocations with a static mode I crack is studied by large scale molecular dynamics simulations. The model consists of a blunted [001] (110) crack in nickel, to which after relaxation at K < Klc the displacement field of a dislocation is added. The response of the system is monitored during its evolution in the microcanonical ensemble. The simulations allowed to identify different characteristic processes during the interaction of the impinging dislocation with the crack. In particular, stimulated dislocation emission and cross slip processes are observed to be important for the development of a plastic zone.