Methods of manufacturing hot-dip galvanized hot-rolled and cold-rolled steel sheets excellent in strain age hardening property
US6814819B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 2003 |
| Grant date | Nov 9, 2004 |
| Priority date | — |
| Expiry date | May 2, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12799
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention provides a steel sheet having a chemical composition comprising 0.15% or less C, 2.0% or less Si, 3.0% or less Mn, P, S, Al and N in adjusted amounts, from 0.5 to 3.0% Cu, or one or more of Cr, Mo and W in a total amount of 2.0% or less, and having a composite structure comprising ferrite and martensite having an area ratio of 2% or more. The steel sheet is in the form of a high-strength hot-rolled steel sheet, a high-strength cold-rolled steel sheet, or a hot-dip galvanized steel sheet. There is thus available a steel sheet excellent in press-formability and in strain age hardening property as represented by a &Dgr;TS of 80 MPa or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.