Mesoscopic Modeling of Primary Recrystallization of AA1050 with Curvature-Driven Interface Migration Effect

Abstract

Primary recrystallization is an important phenomenon involved with cold deformation and heat treatment process. In the present investigation, a two dimensional probabilistic cellular automata model is used to simulate primary recrystallization of cold rolled AA1050, commercially pure aluminum. Electron backscatter diffraction measurement data was used as an input for the simulation to consider highly heterogeneous distribution of the stored energy and orientations compared to the randomly-distributed initial microstructure. Nucleation process was assumed to be site-saturated. Once a nucleus is formed, its recrystallization front will sweep the deformed regions by dissipating the stored deformation energy. In an attempt to contemplate anisotropic property of grain boundary migration, the grain boundary mobility was represented as a function of misorientation and the pressure was expressed as a function of dislocation density difference, curvature, and misorientation. The results of CA simulations were compared well with the JMAK theory in order to investigate the effects of nucleation criteria and curvature-driven pressure on the microstructure and the kinetics of primary recrystallization. This study revealed that local interface migration by curvature-driven pressure could significantly affect the recrystallization kinetics and microstructure morphology depending on the nucleation criteria.