In face-centered cubic crystals, dislocations were dissociated into partial dislocations and, therefore, restricted to move on {111} glide planes. By junction reactions with dislocations on two intersecting {111} planes, Lomer-Cottrell dislocations along 〈110〉 directions could be formed which were barriers for approaching screw dislocations. Treating the interaction between a dissociated screw dislocation and a Lomer-Cottrell lock conventionally, using classical continuum theory and assuming the partials to be Volterra dislocations, leads to erroneous conclusions. A realistic result could only be obtained in the framework of the Peierls model, treating the partials as Peierls dislocations and explicitly taking account of the change in atomic misfit energy in the glide plane. At even moderate stresses (at less than 3 x 10-3µ in Cu), the screw will combine with the Lomer-Cottrell lock to form a Hirth lock. As a result, the nature of the repulsive force will change drastically.

Interaction of Lomer-Cottrell Locks with Screw Dislocations. G.Schoeck: Philosophical Magazine, 2010, 90[5], 629-36