High strength steel sheet and method for manufacturing the same
US10590505B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 14, 2016 |
| Grant date | Mar 17, 2020 |
| Priority date | — |
| Expiry date | Dec 3, 2036 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C18/00
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A high-strength steel sheet having a composition containing C: 0.09% to 0.17%, Si: 0.6% to 1.7%, Mn: 3.5% or less, P: 0.03% or less, S: 0.005% or less, Al: 0.08% or less, N: 0.006% or less, Ti: 0.05% or less, and B: 0.0002% to 0.0030% on a mass basis, the remainder being Fe and inevitable impurities. The steel sheet also has a microstructure containing less than 20% (including 0%) of a ferrite phase, 75% or more (including 100%) of a tempered martensite phase, 10% or less (including 0%) of an untempered martensite phase, and less than 5% (including 0%) of a retained austenite phase in terms of area fraction. The tempered martensite phase has a Vickers hardness of 280 to 340 and a tensile strength of 950 MPa to 1,120 MPa.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.