Steel sheet, hot-dip galvanized steel sheet and galvannealed steel sheet
US11274356B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 2017 |
| Grant date | Mar 15, 2022 |
| Priority date | — |
| Expiry date | Dec 19, 2037 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C28/028
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A steel sheet having a chemical composition of the base metal including, in mass %, C: 0.17 to 0.40%, Si: 0.10 to 2.50%, Mn: 1.00 to 10.00%, P: 0.001 to 0.03%, S: 0.0001 to 0.02%, Al: 0.001 to 2.50%, N: 0.0001 to 0.010%, O: 0.0001 to 0.010%, Ti: 0 to 0.10%, Nb: 0 to 0.10%, V: 0 to 0.10%, B: 0 to 0.010%, Cr: 0 to 2.00%, Ni: 0 to 2.00%, Cu: 0 to 2.00%, Mo: 0 to 2.00%, Ca: 0 to 0.50%, Mg: 0 to 0.50%, REM: 0 to 0.50%, the balance: Fe and impurities, wherein the steel sheet has an internal oxidized layer in which at least one part of a crystal grain boundary is covered by oxides, and in which a grain boundary coverage ratio of oxides is 60% or more in a region from the surface of the base metal to a depth of 5.0 μm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.