Hot Stamping and Press Quenching of Ultrahigh Strength Steel Sheet Using Resistance Heating

The feasibility of hot stamping and press quenching of ultrahigh strength steel sheet using resistance heating was investigated by demonstrating experiments. In the experiments, a rectangular blank of high strength steel sheet, SPFC980Y, 1.2mm thick, 20mm wide and 130mm long was used and it was resistance-heated with a pair of parallel electrodes placed 120mm away from each other, using an AC power supply with a function of input energy control. The relationship between input energy and heating temperature was examined and then hot stamping and press quenching performances were examined. The press quenching was also experimented in hot hat-shaped bending, and the influences of the heating temperature on spring-back and hardness property were investigated. The results of the experiments revealed that hot stamping and press quenching using resistance heating are highly feasible.