Predication of Recrystallization and Mixed Grains in Q235 Steel Produced by CSP Hot Rolling

Q235 steel produced by CSP hot rolling was investigated to determine the occurrence condition of dynamic recrystallization and predicate the recrystallization and mixed grains. The results show that the kinetic model of dynanic recrystallization and dynamic recrystallization criterion for Q235 steel were obtained according to the true stress-true strain curves to predicate the recrystalli-zation and mixed grains, the results of model and criterion were different from the practice, because dynamic recrystallization of partial grains occured in the dynamic recovery sample′s microstructure during the process of thermal simulation. It was necessary to consideration the factors of the storage and release of deformation work when judged accurately the occurrence of the mixed grain.