Hot Stamping of Tailored Component - Experiments and Numerical Analysis

Increased use of ultra-high strength steel in automotive components such as B-pillars and bumper beams leads to decreased weight of vehicles. The high strength and low ductility material can cause failure in joints, e.g. spot welds In this work an omega shaped tool is used for hot stamping of a component with tailored properties. The blank material is Usibor 1500P. Punch and die components of the tool are each designed as a two-part tool piece. One part with high thermal conductivity tool steel and one part with low thermal conductivity tool steel. Trials with different forming forces and holding times are performed. The mechanical strength of the components is estimated by the use of hardness measurements and extraction of tensile test samples. FE-simulations of a typical forming set-up were performed. Numerical and experimental data (hardness and stress-strain curves) were compared and in general the calculated results are in agreement with experiments. hi conclusion, simulation of hot stamping of tailored components gives reasonable results, even based on input data with some degree of uncertainty.