High strength galvannealed steel sheet excellent in workability and a method of production of the same
US7413780B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 26, 2002 |
| Grant date | Aug 19, 2008 |
| Priority date | — |
| Expiry date | Apr 7, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12799
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Galvannealed steel sheet simultaneously able to achieve excellent workability and high strength and a method of production of the same are provided as an objective, in particular high strength galvannealed steel sheet excellent in workability, comprising high strength steel sheet containing, by mass %, C: 0.05 to 0.15%, Si: 0.3 to 2.0%, Mn: 1.0 to 2.8%, P: 0.03% or less, S: 0.02% or less, Al: 0.005 to 0.5%, and N: 0.0060% or less and a balance of Fe and unavoidable impurities, where, when % C, % Si, and % Mn respectively represent the C, Si, and Mn contents, (% Mn)/(% C)≧12 and (% Si)/(% C)≧4 being satisfied, on the surface of which having a galvannealed layer containing Al: 0.05 to 0.5 mass % and Fe: 5 to 15 mass % and a balance of Zn and unavoidable impurities, said steel sheet satisfying a relationship of tensile strength F (MPa) and elongation L (%) of L≧52−0.035×F.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.