BEARING STEEL AND BEARING MEMBER, EXCELLENT IN CHARACTERISTIC OF RETARDING MICROSTRUCTURAL CHANGE DUE TO REPEATED STRESS LOAD AS WELL AS IN HEAT TREATMENT PRODUCTIVITY

摘要

PURPOSE: To attain the improvement of productivity by the inhibition of the formation of a heat treatment decarburized layer and the improvement of service life by the retarding of structural changes during use by specifying a composition and controlling the amount of retained austenite in a structure. ;CONSTITUTION: This steel has a basic composition consisting of, by weight ratio, 0.5-1.5% C, 1.0-2.0% Mo, 0.005-0.015% Sb, 0.0020% O, and the balance Fe with inevitable impurities. If necessary, one or ≥2 kinds selected from among 0.5-2.5% Si, 2.5-8.0% Cr, 1.0-3.0% Ni, 0.012-0.050% N, 0.05-1.0% V, 0.05-1.0% Nb, 0.05-1.0% W, 0.02-0.5% Zr, 0.02-0.5% Ta, 0.02-0.5% Hf, and 0.05-1.5% Co are incorporated as heavy load rolling fatigue life-improving components into the above composition, and further, it is preferable to regulate the amount of retained austenite in the structure of this steel to 10-30% by volume ratio.;COPYRIGHT: (C)1996,JPO