Finite Element Simulation for Hot Stamping of Car Rear Axle Beam Made of 22MnB5 Steel

The hot stamping process of the car rear axle beam made of 22MnB5 steel with the thickness of 3.8 mm was simulated by the finite element analysis software Deform. The temperature changes of the blank during the pressure-holding process after die clamping were analyzed. The hot stamping experiments were conducted on the 22MnB5 steel beam of the rear axle. The temperatures of the blank were measured during the hot stamping process and compared and analyzed with the finite element simulation results. The microstructure and hardness of the beam after hot stamping were also studied. The results show that during the hot stamping process, the temperatures decreased rapidly after die clamping and the cooling rate reached above 30 ℃·s-1, assuring the quenching strengthening of the 22MnB5 steel. The experimental temperature changing curve of the blank during hot stamping was in accordance with the simulated curve and the relative error was below 10%, indicating the accuracy of the simulation results. The microstructure of the hot stamped part consisted of lath martensite and the microhardness reached above 480 HV.