| 摘要 |
Disclosed herein is a process in which a primary steel material is heated through at a heating temperature lying between an Ac1 and an Ac3 temperature, such that at best incomplete austenitising of the primary material takes place, is placed into a press-form tool and formed therein into the formed steel part. The formed steel part is then brought to a bainite forming temperature, which is above the martensite starting temperature, however below the pearlite transformation temperature of the steel, from which the primary material is produced. After cooling it is maintained for an austempering period at the bainite forming temperature in a substantially isothermic manner, until the formed steel part has produced a structure consisting predominantly of ferrite and bainite, the martensite content thereof being < 5%. The formed steel part is then brought to room temperature. |
