Investigation of hot stamping process of 22MnB5 based on metallo-thermo-mechanical theory

摘要

In this study, based on the metallo-thermo-mechanical coupling theory, a FEM model of hot stamping including forming and quenching is built to investigate the cooling behavior and the microstructure evolution, and to predict the final mechanical properties of hot-stamped components. The results show that, after about 16s, the temperature of the entire component is lower than Mf of 22MnB5 boron steel and with a continuous uniform distribution. Most of austenite in component has transformed into martensite. To satisfy the required mechanical properties, the sufficient holding time of quenching in die is essential and it plays an important role in ensuring the required hardness. The predicted Rockwell hardness of component after hot stamping process is almost 512HV, which shows a good agreement with the experimental results. It implies that the metallo-thermo-mechanical numerical model established in this study is reasonable and reliable, which can provide a theoretical guidance for optimizing the hot stamping procedure.