High-strength steel sheet having excellent processability and paint bake hardenability, and method for producing of high-strength steel sheet
US8911567B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 2010 |
| Grant date | Dec 16, 2014 |
| Priority date | — |
| Expiry date | Feb 18, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12799
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The high-strength steel sheet includes, by mass %: C: 0.01% to 0.10%; Si: 0.15% or less; Mn: 0.80% to 1.80%; P: 0.10% or less; S: 0.015% or less; Al: 0.10% to 0.80%; Cr: 0.01% to 1.50%; N: 0.0100% or less; and a balance consisting of iron and inevitable impurities, in which a metallic structure is composed of ferrite and a hard second phase, the area fraction of the ferrite is 80% or more, the area fraction of the hard second phase is 1% to 20%, the fraction of unrecrystallized ferrite in the ferrite is less than 10%, the ferrite grain sizes are 5 μm to 20 μm, and the fraction of the ferrite crystal grains having an aspect ratio of 1.2 or less in the entire ferrite crystal grains is 60% or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.