Steel for gear, gear superior in strength of tooth surface and method for producing same
US5595613A · kind A · utility
18Cited by
1References
9Claims
0Family size
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Key dates
| Filing date | Mar 7, 1995 |
| Grant date | Jan 21, 1997 |
| Priority date | — |
| Expiry date | Mar 7, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C8/22
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A steel for gears consists essentially of 0.10-0.30 wt % of C, not more than 1.0 wt % of Si, not more than 1.0 wt % of Mn, 1.50-5.0 wt % of Cr, and balance including iron and impurity. A gear made by the steel forms a hardened surface layer by carbonizing-hardening-tempering or carbonitriding-hardening-tempering. The amount of C at the hardened surface layer is within a range 0.7 to 1.3 wt %, and the amounts of C, Si and Cr satisfies a relationship 5.5<3.times.C (wt %)+5.2.times.Si (wt %)+Cr (wt %). Therefore, the gear performs superior pitting-resistance and wear-resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.