Method of making hot rolled dual phase steel sheet
US8366844B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 27, 2011 |
| Grant date | Feb 5, 2013 |
| Priority date | — |
| Expiry date | Sep 27, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12799
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method of making hot rolled steel sheet having a dual phase microstructure with a martensite phase of less than 35% by volume and a ferrite phase of more than 50% by volume and a composition containing by percent weight: 0.01≦C≦0.2; 0.3≦Mn≦3; 0.2≦Si≦2; 0.2≦Cr+Ni≦2; 0.01≦Al≦0.10; Mo less than about 0.2%, 0.0005≦Ca≦0.01, with the balance iron and incidental ingredients. Hot rolled sheet for cold rolling, the silicon range may be from about 0.05% to about 2%, and the amount of molybdenum may be up to 0.5%. Also, the hot rolled steel sheet has a tensile strength of at least 500 megapascals, a hole expansion ratio more than about 50%, and a yield strength/tensile strength ratio less than 70%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.