Steel sheet for excellent panel appearance and dent resistance after panel-forming
US5853903A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 1997 |
| Grant date | Dec 29, 1998 |
| Priority date | — |
| Expiry date | Apr 28, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12868
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A cold-rolled steel sheet or a zinc or zinc alloy layer coated steel sheet containing 0.0010 to 0.01 wt % of C and having a steel composition containing one or two kinds of 0.005 to 0.08 wt % of Nb and 0.01 to 0.07 wt % of Ti in the ranges given by {(12/93)Nb+(12/48)Ti*} .gtoreq.0.0005, 0.ltoreq.C-{(12/93)Nb+(12/48)Ti*}.ltoreq.0.0015, and Ti*=Ti-{(48/32)S+(48/14)N } , in which a bake hardenability BH f the steel sheet at 170.degree. C..times.20 min after 2% tensile prestrain is 10 to 35 MPa and the BH (MPa) and a yield strength YP (MPa) of the steel sheet satisfy the ranges given by BH.gtoreq.exp(-0.115.multidot.YP+23.0) and 0.67.multidot.BH+160.ltoreq.YP.ltoreq.-0.8.multidot.BH+280.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.