Steel sheet for hot stamping use, method of production of same, and method of production of high strength part
US10344360B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 2011 |
| Grant date | Jul 9, 2019 |
| Priority date | — |
| Expiry date | Dec 18, 2031 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D8/0273
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention has as its object the provision of steel sheet for hot stamping use which is excellent in part strength after hot stamping and delayed fracture resistance comprised of large C content high strength steel sheet in which effective hydrogen traps are formed in the steel material.The steel sheet of the present invention solves this problem by forming Fe—Mn-based composite oxides in the steel sheet and trapping hydrogen at the interfaces of the composite oxides and matrix steel and in the voids around the composite oxides.Specifically, it provides steel sheet for hot stamping use which is comprised of chemical ingredients which contain, by mass %, C: 0.05 to 0.40%, Si: 0.02% or less, Mn: 0.1 to 3%, S: 0.02% or less, P: 0.03% or less, Al: 0.005% or less, Ti: 0.01% or less, N: 0.01% or less, one or both of Cr and Mo in a total of 0.005 to 1%, and O: 0.003 to 0.03% and which have a balance of Fe and unavoidable impurities and which contains average diameter 0.1 to 15 μm Fe—Mn-based composite oxide particles dispersed in the steel sheet or furthermore has crushed voids around the composite oxide particles, a method of production of the same, and a method of production …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.