Role of Grain Boundary Character Distribution on Dynamic Recrystallization Using Monte Carlo Simulations

Monte Carlo simulations are commonly applied to study microstructural evolution, including abnormal grain growth and recrystallization. Here, Monte Carlo simulations are used to study the effects of grain boundary character distribution on dynamic recrystallization. The initial stored energy is uniformly distributed and a constant strain rate is achieved by incremental increases in stored energy. The simulation tracks the grain size, special boundary fraction, and recrystallization fraction. Recrystallization rates vary with initial special boundary fraction and are compared to kinetic models. Similar to experimental results, a high percentage of grains that nucleate early in the simulation have special-boundary relationships with surrounding grains. As the simulation progresses, the orientation of nuclei becomes nearly random compared to surrounding grains. The simulations also predicted that the final special boundary fraction can be controlled by varying the strain rate. Once correlated with experimental results, the simulation can be used to investigate and refine hot-deformation processes.