High-strength hot rolled steel sheet
US9657382B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 2012 |
| Grant date | May 23, 2017 |
| Priority date | — |
| Expiry date | Jul 22, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12972
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A high-strength hot rolled steel sheets with excellent stretch flangeability has small variations in mechanical properties in individual coils. Variations in strength from place to place in a coil are decreased by minimally reducing the Si and Mn contents to suppress the occurrence of problems such as segregation. Further, the microstructure of the steel sheets is configured such that a ferrite phase represents an area ratio of not less than 95%, the ferrite crystal grains have an average grain size of not less than 1 μm, and the ferrite crystal grains contain TiC with an average particle size of not more than 7 nm dispersed in the crystal grains.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.