A model of creep embodying dislocations whose movements produce work hardening and recovery

In conformity with contemporary views, the new model envisages that the initial period of decreasing strain-rate (i.e. primary creep) is due to immobilization of dislocations but it also incorporates the concept of their remobilization by a thermally activated process ( such as climb). The resulting creep-equation successfully represents the pattern of behaviour observed when, during an experiment, the stress causing creep is removed, reduced or increaeed. It correctly simulates the accelerating creep which occurs for a period At after the stress has been reduced by Delta sigma, mirrors the tendency for At to vary with Delta sigma and describes the experimentally observed dependence upon strain-rate and stress of the Baily-Orowan recovery parameter, r(r similar to-Delta sigma/Delta t).