A new unified approach for modeling recrystallization during hot rolling of steel

Recrystallization during hot rolling of steel and the developing austenite grain size play an essential role for the phase transformation during cooling and the resulting mechanical properties. Thus, many models for recrystallization were developed in the past decades. While constitutive models are still state-of-the-art for online process control, mesoscale models with a spatial representation of the microstructure can provide better predictive capabilities at the cost of long computation times. To fill this gap a new approach based on modeling the interaction of an ensemble of multiple grains is proposed. Simulation results with this new model are in good agreement with results from experiments with a heat treatable 42CrMo4 steel. It is shown that the model can also describe the behavior under transient conditions known from experimental investigations and cellular automata models.