Modeling of nucleation during recrystallization

Abstract

The number density and spatial distribution of nuclei determine the kinetics, and the evolution of microstructure and texture during recrystallization. The potential nucleation sites are the high angle boundaries that exist in the deformed microstructure. These could be either the original grain boundaries prior to deformation or boundaries created due to non-uniform plastic deformation on the microscopic scale. Discontinuous subgrain growth with or without the formation of high angle boundaries may also occur during recrystallization in the presence of long range orientation gradients existing in the deformation substructure. The paper presents Monte Carlo simulation results on the evolution of substructures for each of the above nucleation mechanisms. The evolution of recrystallized grain structure from a realistic substructure obtained by modeling the deformation of fcc polycrystals at the microstructural level is presented, and shows the collective contribution of the above nucleation mechanisms during recrystallization and grain growth. The simulations capture not only the kinetics and microstructural evolution but also the evolution of texture during recrystallization.