In delay property and heat treatment productivity of the microstructure change due to repeated stress load is superior the bearing steel

摘要

PURPOSE: To improve rolling fatigue life and heat treatment productivity by specifying respective contents of C, Mo, Al, Sb, Si, Mn, Cr, etc., and controlling the grain size of oxide non-metallic inclusions. ;CONSTITUTION: The bearing steel has a composition consisting of, by weight, 0.5-1.5% C, 0.5-2% Mo, 0.005-0.07% Al, 0.001-0.05% Sb, and the balance Fe or further containing, besides the above, one or more kinds selected from 0.05-0.5% Si, 0.05-2% Mn, 0.05-2.5% Cr, 0.05-1% Ni, 0.05-1% Cu, 0.0005-0.01% B, and 0.0005-0.012% N. Moreover, the maximum grain size of oxide non-metallic inclusions is regulated to ≤8μm. By this method, working load at the time of heat treatment can be reduced and microstructural change due to repeated stress load at the time of heavy load rolling can be retarded, and heavy load rolling fatigue life can be improved.;COPYRIGHT: (C)1994,JPO