An apparent conflict between 2 experimental estimates (Bordoni peak experiment, low-temperature plastic-flow measurement) of the Peierls stress in face-centered cubic metals was resolved within the standard Peierls model for dislocation dynamics. It was proved that the Peierls stress was correctly estimated by Bordoni peak experiments, and that the ratio of the conflicting estimates was proportional to the dislocation damping constant. The key factor in the resolution was the recognition of inertia. That is, of dynamic effects which were due to the smallness of the viscous force which acted upon the dislocation line. This was definitely true of face-centered cubic metals such as Cu, where the discrepancy was greatest. The relevance of inertial effects to plastic-flow mechanisms had been remarked before, in both this and other contexts. At low temperatures, Bordoni relaxation in the locked state and in the presence of high dislocation mobility were both observable; depending upon the intensity of the applied stress relative to the unlocking threshold. The apparent absence of the discrepancy in body-centered cubic metals was tentatively attributed to the facts that the dislocation damping in body-centered cubic metals was greater than in face-centered cubic metals, or that the Peierls stress was smaller. Experimental evidence suggested that this might be true.

On Two Conflicting Estimates of the Peierls Stress. F.Marchesoni, C.Cattuto: Philosophical Magazine A, 1998, 77[5], 1223-9