The core structure and Peierls stress of dissociated ½<110> dislocations in face-centered cubic Ni was determined by using atomistic molecular dynamics simulations, and an EAM potential. The edge dislocation was observed to dissociate along a path that corresponded to the crystallographic Burgers vector of partials. The separation distance between partials was found to be a multiple of the lattice constant. Under the action of an external stress, the partials moved in phase and behaved globally as a rigid complex. The Peierls stress for a single partial was close to the effective Peierls stress for the extended dislocation. In the screw dislocation, the separation distance was smaller and close to a half-integer of the lattice constant. The strong core-overlap produced a significant reduction in the lateral Burgers vector during the dissociation process. Under stress, the partials moved out-of-phase and the separation distance underwent some modulation. In this case, the effective Peierls stress was smaller than the Peierls stress for partials.

Computational Study of Core Structure and Peierls Stress of Dissociated Dislocations in Nickel. P.Szelestey, M.Patriarca, K.Kaski: Modelling and Simulation in Materials Science and Technology, 2003, 11[6], 883-95