New Type Austenite Dynamic Recrystallization of Microalloyed Forging Steels 38MnVS During Forging Process

Hot compression tests of microalloyed forging steels 38MnVS were carried out on the Gleeble-3800 thermo-mechanical simulator at the deformation temperatures from 950 to 1150 °C with the strain rates ranging from 0.1 to 10 s−1. The effects of the deformation temperature and strain rate on the austenite dynamic recrystallization and microstructural changes were researched. The experimental results show that the dynamic recrystallization accelerated with the increase of the deformation temperatures and the decrease of the strain rate. The activation energy of dynamic recrystallization was calculated, which was about 275.453 kJ/mol. The relation between the dynamic recrystallization and the Z-parameter was investigated, and the state chart of the dynamic recrystallization of the micro-alloyed forging steel 38MnVS was made according to the experimental data and the deformation parameters.