Deformation behaviour of high strength steel sheet 22MnB5 at elevated temperature and its FE simulation model verification

The hot ductility and fracture behaviour of boron steel 22MnB5 is of significant importance in the development of new components based on the hot stamping process. It is well known that the strain rate and temperature have remarkable influence on the ductility and fracture behaviour of boron steel 22MnB5. In the paper, the uniaxial tensile tests were carried out at elevated temperatures, in a range between 550°C and 850°C, at different strain rates, to investigate the hot ductility of boron steel at high temperature. In order to discover the fracture mechanisms under hot tensile testing, fracture surface observations were performed by scanning electron microscope (SEM). Finite element (FE) model of the experiments was developed and successfully validated against the experimental results. The predicted force-displacement curves indicate the proposed FE model is able to predict the ductile fracture onset in hot stamping.