Steel sheet and method for producing same
US12221666B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 15, 2019 |
| Grant date | Feb 11, 2025 |
| Priority date | — |
| Expiry date | Sep 16, 2041 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/008
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Provided is a steel sheet having a predetermined chemical composition and structure wherein (Fe, Mn)2B precipitates having a circle equivalent diameter of 50 to 300 nm are present in a number density of 1/500 μm2 or more in a surface layer region down to a depth of 100 μm from the surface in the sheet thickness direction. Further, provided is a method for producing a steel sheet comprising continuously casting a molten steel having a predetermined chemical composition to form a steel slab, wherein the continuously casting includes introducing more than 10 ppm and less than 100 ppm of oxygen into the surface layer of the steel slab, hot rolling including finish rolling the steel slab, wherein a completion temperature of the finish rolling is 650 to 950° C., coiling the obtained hot rolled steel sheet at a coiling temperature of 400 to 700° C., and cold rolling the hot rolled steel sheet, then annealing it.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.