In face-centred cubic crystals, dislocations were dissociated on the {111} glide plane into pairs of partial dislocations. Since each partial interacts individually with the Peierls potential and was coupled to its neighbour by a stacking fault, periodic variations in the separation distance d of the partials occurred when dislocations running along closed packed lattice directions were displaced. This could drastically reduce the effective Peierls stress. By using the Peierls model the structure of 0°, 30°, 60° and 90° dislocations in a typical face-centered cubic metal with the elastic properties of Cu and a stacking-fault energy in the interval of 0.04 to 0.05J/m2 was studied, and the magnitude of the Peierls energy and the resulting kink energies were determined. Since the energies involved were of the order of 10-3eV/b or less, their magnitude cannot be asserted with high confidence, considering the simplifying assumptions in the model. The difference in the changes of the core configuration during displacement of dislocations of different orientations should, however, be of physical significance. It was found that a dissociated 60° dislocation generally has a higher effective Peierls energy than a screw dislocation, but the reverse was true for the kink energy, at least in Cu.

The Peierls Energy and Kink Energy in FCC Metals. G.Schoeck, M.Krystian: Philosophical Magazine, 2005, 85[9], 949-66