Manufacturing method for hot press formed steel member
US9359663B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 17, 2014 |
| Grant date | Jun 7, 2016 |
| Priority date | — |
| Expiry date | Jan 17, 2034 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/008
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Provided is a method for manufacturing a hot press formed steel member that has high strengths, an excellent balance between strength and ductility, and good deformation properties upon crush on collision (crashworthiness). The manufacturing method is highly efficient and allows a high degree of freedom with respect to the shape to be formed. The method manufactures a steel member by heating a steel sheet having a specific chemical composition and subjecting the steel sheet to at least one time of hot press forming. In the method, the heating temperature is equal to or higher than the Ac3 transformation temperature, and a starting temperature of the hot press forming is in the range from the heating temperature to martensite start (Ms) temperature. Cooling from [(Ms temperature)−150° C.] down to 80° C. is performed so that a tempering parameter (λ) specified by Expression (1) is in the range from 7100 to 8030.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.