| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot-pressing method for a steel sheet capable of obtaining high strength after high temperature forming. SOLUTION: In the hot-pressing method for a steel sheet, a steel sheet comprising, by mass,≥0.15% C is heated to≥850°C, thereafter, while cooling is performed at a cooling rate of≥10°C/s, press forming starting temperature Tp[°C] is controlled to≤600°C, press forming finishing temperature is controlled to the martensite transformation starting temperature Ms[°C] of the steel sheet or above, then, press forming is performed, and subsequently, the steel sheet is cooled to≤300°C at a cooling rate of≥10°C/s. Preferably, press forming time tp[s] is controlled to≤20s, and tp≤(Tp-Ms)/100 is satisfied. COPYRIGHT: (C)2008,JPO&INPIT
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