High strength cold rolled steel sheet and method for manufacturing the same
US9534269B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 2013 |
| Grant date | Jan 3, 2017 |
| Priority date | — |
| Expiry date | Oct 21, 2033 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/008
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method of manufacturing a high strength cold rolled steel sheet includes hot-rolling and cold-rolling a steel slab annealing the steel sheet at an annealing temperature of 750° C. to 830° C.; subjecting the steel sheet to first cooling at an average cooling rate of 3° C./sec to 40° C./sec in a temperature range from the annealing temperature to 480° C.; subjecting the steel sheet to second cooling at an average cooling rate of 8° C./sec to 80° C./sec in a temperature range from 480° C. to Tc (° C.) given by formula (6):Tc=435−40×[% Mn]−30×[% Cr]−30×[% V] (6)wherein [% A] is the content (% by mass) of alloying element A; and subjecting the steel sheet to third cooling at an average cooling rate of 0.3° C./sec to 30° C./sec in a temperature range from Tc (° C.) to 200° C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.