Hot-pressed member, cold-rolled steel sheet for hot-pressed member, and method for producing the same
US11850821B2 · kind B2 · utility
2Cited by
1References
4Claims
0Family size
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Key dates
| Filing date | Dec 26, 2019 |
| Grant date | Dec 26, 2023 |
| Priority date | — |
| Expiry date | Jun 23, 2040 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D3/22
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A hot-pressed member has a predetermined chemical composition. In the hot-pressed member, a steel sheet has a microstructure in which a prior austenite average grain diameter is 8 μm or less, and martensite is present in a volume fraction of 95% or greater in a region within 30 μm of a surface; a Ni diffusion region having a thickness of 0.5 μm or greater exists in a surface layer; a standard deviation of Vickers hardness values is 35 or less; Mndif (mass %) in a sheet thickness direction ≤0.20, where Mndif (mass %) is a degree of Mn segregation; and a tensile strength is 1780 MPa or greater.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.