Study on the Hot Stamping of Rectangular Box with Ultra-High Strength Steel

Hot stamping of the ultra high strength steel (UHSS) was studied to meet the requirements of lightweight of automobile. The coupled thermo-mechanical model for hot stamping was established with ABAQUS. Initial temperature of tools (die, punch, blank holder) and stamping speed were studied to insure the impact on the thickness, stress and strain of blank. It shows that punch fillet area is easy to crack. With the temperature of tools increasing, the sheet minimum thickness increases first and then decreases. With the increase of punch velocity, the sheet minimum thickness increases. Compared with the initial temperature of tools, punch velocity has a greater impact on the thickness. The simulation results are in agreement with the experimental results and provide a theoretical basis for the practical stamping process.