Case hardening steel material
US9777354B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Apr 16, 2013 |
| Grant date | Oct 3, 2017 |
| Priority date | — |
| Expiry date | Nov 16, 2033 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/009
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A case hardening steel material having a chemical composition consists of, by mass percent, C: 0.15 to 0.23%, Si: 0.01 to 0.15%, Mn: 0.65 to 0.90%, S: 0.010 to 0.030%, Cr: 1.65 to 1.80%, Al: 0.015 to 0.060%, and N: 0.0100 to 0.0250%, further containing, as necessary, one or more kinds selected from Cu and Ni of predetermined amounts, the balance being Fe and impurities; 25≦Mn/S≦85, 0.90≦Cr/(Si+2Mn)≦1.20, and 1.16Si+0.70Mn+Cr≧2.20; P, Ti and O in the impurities being P≦0.020%, Ti≦0.005%, and O≦0.0015%; and having a structure consisting of 20 to 70% in an area ratio being ferrite; and the portion other than the ferrite being one or more kinds of pearlite and bainite. The steel material is used suitably as a raw material of the carburized part such as a CVT pulley shaft.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.