A thermodynamically consistent model for elastoplasticity, recovery, recrystallization and grain coarsening

We present a model for the thermomechanical behaviour and microstructure evolution of metallic materials during thermomechanical processing. Special emphasis is put on its derivation based on the Müller–Liu procedure which ensures consistency with fundamental physical principles. The model represents in principle the strong coupling between elastoplastic deformation, recovery, recrystallization, grain coarsening and related thermal effects. Furthermore, it takes the dragging effect of precipitates on grain boundaries and dislocations into account by which a higher strength can be achieved and the grain size is stabilised. For the microstructure description, we use a mean-field approach. In several numerical examples, we demonstrate the capability of the model to consistently predict the interplay between elastoplastic deformation, microstructure evolution, dynamic hardening and softening and the related temperature change.