| 摘要 |
A method of manufacturing a steel part including hot stamping followed by trimming, piercing, or flanging, without delayed fracture and without the need for annealing, is provided. The method includes heating a blank formed of a steel material, forming the blank between a pair of dies, and quenching the blank. The temperature drop in select areas of the blank is reduced, which limits the amount of martensite formed in the select areas, but allows martensite to form in other areas. The dies can be formed with modified materials or modified cooling channels to limit the amount of martensite formed in the select areas of the blank. The select areas are softer than the other areas and can be subsequently trimmed, pierced, or flanged without the delayed fractures. |
