Bearing part, heat-treatment process for this purpose and roller bearings

摘要

A bearing part with a long service life compared with rolling contact fatigue, and excellent an ultimate tensile strength, the change in dimension with respect to age-related displacement is limited for this purpose, a heat-treatment process, and a roller bearing, which contains the bearing part, are achieved. Steel for a bearing part (1, 2, 3) is a carbonitriding in the case of a carbonitriding temperature (t₁) subjected to the a₁ Transition temperature and is cooled to a temperature which is lower than the a₁ Transition temperature. The steel is to a curing temperature (t₂) heated again, the not lower than the a₁ Transition temperature, but lower than the carbonitriding temperature, and then hardened.