Fracture-tough, high hardness stainless steel and method of making same
US5221372A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 13, 1992 |
| Grant date | Jun 22, 1993 |
| Priority date | — |
| Expiry date | Feb 13, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D8/005
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A cryogenically-formed and tempered stainless steel is provided having improved fracture toughness and corrosion resistance at a given hardness level, such as, for example, of at least about Rc 60 for bearing applications. The steel consists essentially of, in weight %, about 21 to about 24% Co, about 11 to about 13% Cr, about 7 to about 9% Ni, about 0.1 to about 0.5% Mo, about 0.2 to about 0.3% V, about 0.28 to about 0.32% C, and the balance iron. The steel includes a cryogenically-formed martensitic microstructure tempered to include about 5 to about 10 volume % post-deformation retained austenite dispersed therein and M.sub.2 C-type carbides, where M is Cr, Mo, V, and/or Fe, dispersed in the microstructure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.