On the strain-rate dependence of dynamic recrystallization in copper polycrystals

Dynamic recrystallization (DRX) is thought of as essentially a competition between hardening processes (dislocation accumulation) and restitution processes (recrystallization). The current paper has essentially two parallel aims: to study similarities and possible connections between dynamic recovery and dynamic recrystallization: and to assess the effects of strain rate on DRX quantitatively. First, we will analyze the experimental stress strain curves to see whether a rule can be found that characterizes the beginning of DRX - the assumption being that it may be related to some property of the deformed state. Then, we will attempt to find a scaling procedure for the entire DRX behaviour, single - or multiple-peak, that reduces the data to a single curve, or a simple set of curves. We will find that the asymptotic steady-state flow stress (or the mean stress in continued oscillations) is a helpful parameter As a last step, the kinetics of this DRX parameter will be analyzed: it will be found to be similar, but not identical, to that of dynamic recovery. Finally, the discussion will address conclusions and open questions.