Method for producing a high strength steel sheet having improved strength and formability and obtained sheet
US11555226B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 3, 2015 |
| Grant date | Jan 17, 2023 |
| Priority date | — |
| Expiry date | May 22, 2036 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/008
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method for producing a high strength uncoated steel sheet having an improved strength and an improved formability, including the steps of: providing an uncoated steel sheet; annealing the sheet at an annealing temperature TA higher than 865° C. but less than 1000° C. for a time of more than 30 s; cooling the sheet down to a quenching temperature QT between 310° C. and 375° C., at a cooling speed of at least 30° C./s; heating the sheet up to a partitioning temperature PT between 370° C. and 470° C. and maintaining the sheet at the partitioning temperature for a partitioning time Pt between 50 s and 150 s; and cooling the sheet down to the room temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.