BEARING MEMBER EXCELLENT IN CHARACTERISTIC OF RETARDING MICROSTRUCTURAL CHANGE DUE TO REPEATED STRESS LOAD AND ALSO IN HEAT TREATMENT PRODUCTIVITY

摘要

PURPOSE: To improve rolling fatigue life by allowing specific amounts of residual austenite to exist in a steel structure containing specific amounts of C, Al, Sb, O, and Fe. ;CONSTITUTION: This steel has a composition consisting of, by weight, 0.5-1.5% C, 0.07-1% Al, 0.001-0.015% Sb, ≤0.002% O, and the balance essentially Fe and further containing one or more kinds selected from 0.05-0.5% Si, 0.05-2% Mn, 0.05-2.5% Cr, 0.05-0.5% Mo, 0.05-1% Ni, 0.05-1% Cu, 0.0005-0.01% B, and 0.0005-0.012% N. Moreover, this steel has a steel structure in which the amount of redidual austenite in the steel is regulated to 10-35% by volume ratio. By this method, even under severe conditions of heavy load and high temp. under a dusty environment, a microstructural change due to repeated stress load in the surface layer part of a bearing member can be retarded.;COPYRIGHT: (C)1995,JPO