HEAT TREATMENT METHOD OF BEARING

摘要

The method comprises; diffusively implanting softening resistant atoms in surface layer of high carbon chrome bearing steel by heating the bearing steel at 800-900 deg.C for 2-3 hours under ammonia gas containing the softening resistant atoms; quenching the bearing steel in the oil bath of 40-120 deg.C; cooling the quenched bearing steel at below zero deg.C after maintaining it at room temperature; and tempering the cooled bearing steel at 200-350 deg.C for 1-2 hours. The method improves a dimensional stability at high temperature and prevents the lowering of hardness.