Good-workability and high-strength cold-rolled steel sheet excellent in post-painting corrosion resistance
US7678204B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Dec 9, 2003 |
| Grant date | Mar 16, 2010 |
| Priority date | — |
| Expiry date | Dec 9, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/902
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention: provides a good-workability and high-strength cold-rolled steel sheet excellent in post-painting corrosion resistance to the extent of securing excellent resistance to salt warm water immersion which is a good-workability and high-strength cold-rolled steel sheet excellent in post-painting corrosion resistance characterized in that: said steel sheet contains, in mass, 0.16 to 0.19% C, 1.10 to 1.30% Si, 1.50 to 1.60% Mn, not more than 0.1% P and 0.015 to 0.050% Al, with the balance consisting of Fe and unavoidable impurities; the average of the amount of Si incrassating on the surface of said steel sheet is not more than 20 times the Si concentration in said steel sheet; and the area percentage of the portions where the ratio of the Si concentration on the surface of said steel sheet to the Si concentration in said steel sheet is not less than 10 is not more than 95%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.