High strength galvanized steel sheet exhibiting excellent fatigue property
US9044920B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2011 |
| Grant date | Jun 2, 2015 |
| Priority date | — |
| Expiry date | Nov 12, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12667
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A high strength galvanized steel sheet having tensile strength of 590MPa or more which is excellent in fatigue property in punching work, and a manufacturing method thereof are provided. The microstructure includes a ferrite phase having an average grain diameter of 15 μm or less and an area fraction of 60% or more and a martensite phase having an area fraction of 5 to 40%, and an amount of one or more kinds of oxide selected from a group consisting of Fe, Si, Mn, Al, P, Nb, and Ti generated on a surface layer portion of the steel sheet within 100 μm in a steel-sheet-side depth direction from a surface of a base steel sheet directly below a galvanized layer is less than 0.060 g/m2 per one-side surface of the steel sheet.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.