Modeling the Effects of Processing Parameters on Dynamic Recrystallization Behavior of Deformed 38MnVS6 Steel

The dynamic recrystallization (DRX) and grain growth mathematical models of 38MnVS6 steel were obtained on the basis of the results from hot compression tests and isothermal annealing tests on a Gleeble-1500 thermo-mechanical simulator. A three-dimensional finite element model was established to investigate the compression process. In order to predict the evolution of DRX volume fraction and austenite grain sizes, a subprogram was designed and coupled in the FE model. The effects of deformation temperatures and strain rates on microstructural evolution and distribution of 38MnVS6 steel during hot compression process were simulated. The simulated results show that the distributions of DRX volume fraction are inhomogeneous in the deformed workpiece, and the degree of DRX increases with increasing deformation temperature and decreasing strain rate. The average rate of DRX increases with the increase of deformation temperature and strain rate. Additionally, with the decrease of deformation temperature and the increase of strain rate, the inhomogeneity of DRX grain sizes increases and the average complete DRX grain sizes become finer. The simulated values of average complete DRX grain sizes show a good agreement with the measured ones.