The coupled thermo-mechanical-microstructural finite element modeling of hot stamping process in 22MnB5 steel

In this study, a coupled thermo-mechanical-microstructural finite element model based on the subroutine of commercial software ABAQUS is developed to predict the hot stamping process in 22MnB5 steel. The Johnson–Mehl–Avrami–Kolmogorov type model with Scheil’ additivity rule and Koistinen–Marburger model are adopted to simulate the diffusional phase transformation and diffusionless one respectively. During the calculation of temperature and stress/strain field, the contributions of microstructure evolution, e.g. transformation latent heat, transformation strain, and transformation plasticity are taken into account, which give more insight of the material response. The model allows to evaluate the transient stress and strain distributions, the final microstructure constituent and the final distortion of the sheet part during the press quenching process. The effect of transformation plasticity on the geometry precision and the residual stress are discussed.