Numerical simulation of the intersection of a moving ½[110] screw dislocation with a perfect stacking-fault tetrahedron in a face-centered cubic Ni crystal was carried out by using molecular dynamics for various many-body potentials. When the glide plane of the screw dislocation coincided with one of the planes of the stacking-fault tetrahedron, the interaction involved several dislocation reactions, jog-line formation and bending of dislocation segments. The complex atomic processes were illustrated in detail and were shown to depend upon the relative orientation of the defect and the moving dislocation. In most cases, the jogs disappeared quickly but, in special cases, the jog-lines in the dissociated dislocation remained even after interaction with the stacking-fault tetrahedron; thus dragging some vacancies away. While in this geometrical set-up, the main effect of the intersection was ledge formation on the stacking-fault tetrahedron, when the moving dislocation intersected the stacking-fault tetrahedron in the middle part, it led to slip and to separation of the stacking-fault tetrahedron into 2 parts. If the screw dislocation passed at a non-zero distance from the stacking-fault tetrahedron, the elastic interaction did not lead to any deformation of the stacking-fault tetrahedron.

Computational Study of a Screw Dislocation Interacting with a Stacking-Fault Tetrahedron. P.Szelestey, M.Patriarca, K.Kaski: Modelling and Simulation in Materials Science and Engineering, 2005, 13[4], 541-51