It was noted that, in the anomalous yield stress regime, the strain-rate dependence, , of the flow stress, , was proportional to (-y), where y was the stress which was required to bow out edge dislocations to a near-critical Frank-Read source configuration, at a level which was equal to that required for the dynamic propagation of screw dislocations. In the micro-strain region, the source dislocations were predicted to form loops that were elongated along the screw direction. Experiments on the so-called partial reversibility of the yield stress with temperature were described, and it was shown that  was not reversible. However, the yield stress was instantaneously partially reversible. This was attributed to the instability, and running back, of some dislocation loops in the micro-strain region during unloading. The temperature dependence of / was found to reflect the effect of various obstacles at certain temperatures. The temperature and strain-rate dependences of the flow stress were analyzed in terms of a model in which the critical step was the operation of Frank-Read sources.

S.S.Ezz, P.B.Hirsch: Philosophical Magazine A, 1995, 72[2], 383-402