Development and application of a new hot-work die steel for hot stamping

A new hot-work die steel for hot stamping was developed, and used the die for mass production. The produced die showed good performance owing to its high heat conductivity and wear-resistant characteristics. Two different benchmarking hot-work die steels were investigated, and then compared in terms of their impact ductility, temper characteristics ,heat conductivity, and thermal stability. The result of the high-temperature friction wear test indicated that oxidative wear was the main mode in high temperature. On the basis of the comparison and test results, the alloying composition of the new hot-work die steel was especially designed. The new die steel showed good performance with good wear-resistant quality, as well as temper hardness and heat conductivity of HRC 50 and 34.3 W/（ m ~ K）, respectively. Furthermore, without surface plasma nitriding, the die made of the new steel had no obvious galling with 6 142 strokes. After surface plasma nitriding, the die completed 40 000 strokes with good surface. The die life is expected to exceed 200 000 strokes.