High-strength steel sheet
US11486028B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 2019 |
| Grant date | Nov 1, 2022 |
| Priority date | — |
| Expiry date | Oct 14, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C2202/00
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
What is provided is a high-strength steel sheet having a large bake hardening amount and a uniform bake hardenability is provided according to the present invention, the high-strength steel sheet comprising, by mass %: C: 0.13% to 0.40%; Si: 0.500% to 3.000%; Mn: 2.50% to 5.00%; P: 0.100% or less; S: 0.010% or less; Al: 0.001% to 2.000%; N: 0.010% or less; and a remainder consisting of Fe and impurities, wherein martensite is 95% or more in an area ratio, and residual structure is 5% or less in an area ratio, a ratio C1/C2 of an upper limit C1 (mass %) of Si concentrations to a lower limit C2 (mass %) of the Si concentrations in a cross section in a thickness direction is 1.25 or less, precipitates having a major axis of 0.05 μm or more and 1.00 μm or less and an aspect ratio of 1:3 or more are included in a number density of 30/μm2 or more, and a tensile strength is 1300 MPa or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.