A new model of solution-hardening in face-centred cubic metals assumed that dislocation motion was controlled by a thermal activation process. The interaction of a dislocation with several solute atoms was taken into account in a single activation event. The actual number of solute atoms which were involved in an activation event was determined by minimizing the activation energy. The model predicted a temperature dependence, of the flow stress, that agreed reasonably well with experimental results. In particular, it predicted the appearance of an inverse temperature dependence of the flow stress in the low-temperature region. Thus, the anomalous lowering of the flow stress at low temperatures, observed in some dilute alloys, could be explained by the dislocation-solute atom interaction alone. This was compared with the conventional explanation, in which the so-called inertial

effect was invoked. Another feature of the new model was that it provided a simple explanation for the occurrence of the stress equivalence phenomenon.

A New Model of Solution Hardening in FCC Metals Based on the Interaction with Plural Obstacles. K.Marukawa: Philosophical Magazine, 2007, 87[26], 4027-46