4. Results and discussions
4.1. Effects of die design with movable pad
hot stamping experiments were implemented for front door beam. Without movable pad design,
a front door beam with fracture in twin-U area. Seen from the figure, the position of fracture is at
the sharp corner (twin-U area), and that is completely consistent with the simulation prediction. However, sound
part (no fracture) was formed with movable pad design In the simulation, the minimum
thickness of sheet is 1.18 mm and the thinning ratio is 15.7%. That was compared to the experimental thickness
distribution . The minimum thickness of sheet is 1.08 mm and the thickness thinning ratio is
22.8%. The results indicate the process parameters adopted in the paper is reliable, and the simulation results were
in acceptable consistence with experimental data.