Behaviour of dissociated dislocations with sessile cores

The behaviour of dislocations dissociated into two partials, dislocations which are not freely mobile on the plane of dissociation has been studied in the frame of a model where the frictional force is described by a simple Peierls-Nabarro potential. In addition to the dislocations exhibiting the equilibrium separation of the partial dislocations, the metastable partial separations are also considered. To study the dynamics of dislocation processes, including the effect of the applied stress, a stochastic model based on the Monte Carlo method has been developed. Changes in the dislocation width distribution, caused by thermally activated jumps between dislocation states with differing width of dissociation, have been investigated for several starting configurations of the simulated dislocation ensemble.