Study on the thermo-mechanical-metallurgical couple model of tailored hot stamping

In order to predict the microstructures and hardness evolution of tailored hot stamping (THS) component, a thermo-mechanical-metallurgical couple finite element model was established. In particular, the activation energies for ferrite and bainite in the model were optimised. THS experiment of U-shape component with segmented heating and cooling was also performed to compare the hardness distribution and phase change with numerical simulation. The results showed that the original model and the activation energy optimised model can both be used to predict the microstructures and hardness evolution for hot stamping components with full martensite. As for THS component, the effect of cooling path and deformation on the activation energies of phase transformation should be considered.