High-strength hot-dip galvannealed steel sheet with superior phosphatability
US8697252B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 7, 2008 |
| Grant date | Apr 15, 2014 |
| Priority date | — |
| Expiry date | Feb 1, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12972
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Disclosed is a hot-dip galvannealed steel sheet that stably exhibits satisfactory phosphatability. It is a high-strength hot-dip galvannealed steel sheet which includes a base steel sheet and, arranged on at least one side thereof, an Fe—Zn alloyed galvanized layer. The base steel sheet contains 0.03% to 0.3% of carbon, 0.5% to 3.0% of silicon, and 0.5% to 3.5% of manganese, with the remainder including iron and inevitable impurities. The Fe—Zn alloyed galvanized layer has a concentration of silicon present as an oxide of [Si] (percent by mass) and a concentration of manganese present as an oxide of [Mn] (percent by mass), and these parameters satisfy the following conditions (1) and (2):[Si]≦0.25 (1)[Mn]/[Si]≦3.0 (2).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.