Tempered and coated steel sheet having excellent formability and a method of manufacturing the same
US12065724B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2017 |
| Grant date | Aug 20, 2024 |
| Priority date | — |
| Expiry date | Mar 5, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/008
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A tempered and coated steel sheet having a composition containing the following elements, expressed in percentage by weight: 0.17%≤carbon≤0.25%, 1.8%≤manganese≤2.3%, 0.5%≤silicon≤2.0%, 0.03%≤aluminum≤1.2%, sulphur≤0.03%, phosphorus≤0.03%, the remainder composition being composed of iron and unavoidable impurities caused by processing, the microstructure of said steel sheet containing in area fraction, 3 to 20% residual austenite, at least 15% of ferrite, 40 to 85% tempered bainite and a minimum of 5% of tempered martensite, wherein cumulated amounts of tempered martensite and residual austenite is between 10 and 30%. The composition may also contain one or more of the following elements chromium≤0.4%, molybdenum≤0.3%, niobium≤0.04%, titanium≤0.1%. Methods of manufacturing and use of the tempered and coated steel sheets are also described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.