Steel sheet excellent in coating sharpness, defect-formation resistance and workability
US5532051A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 1994 |
| Grant date | Jul 2, 1996 |
| Priority date | — |
| Expiry date | Aug 25, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31678
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
To obtain a high tensile strength steel sheet which has an improved lubricating ability during press working, coating sharpness and defect-formation resistance, and which is useful as an outer plate of automobiles and electrical appliances, by forming uniform recesses and protrusions thereon and regulating the shapes of the recesses and protrusions, the recesses each having a flat portion at their bottom, and the size of the protrusion top faces, the depth between the recesses and the protrusions and the peak-to-peak distance being restricted. The recesses and protrusions formed thereon satisfy the following conditions; oil pools are formed thereon in an area covering 30% of the surface thereof; the top faces of the protrusions each having a size of 10 to 450 .mu.m; the level difference between the recesses and the protrusions being from 2 to 20 .mu.m; the peak-to-peak distance of the protrusions being from 50 to 1000 .mu.m; P and D satisfying the relationship 2.2<P/D<5, and the recess area being at least 85%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.