Modelling of microstructure development by means of a dislocation-disclination reaction kinetics

The microstructure development under plastic deformation up to large strains is modelled by means of a four-component reaction kinetics for the densities of mobile and immobile dislocations and disclinations. The resulting system of nonlinear differential equations is able to describe the transition from a dislocation-dominated to a disclination-controlled kinetics finally running into an instability. A relationship between the density of sessile disclinations and the flow stress is proposed using a Hall-Petch type relation for subgrain-size strengthening. (C) 1997 Published by Elsevier Science B.V.