BEARING STEEL EXCELLENT IN DELAY CHARACTERISTIC OF CHANGE IN MICROSTRUCTURE CAUSED BY REPEATED STRESS LOAD

摘要

PURPOSE: To delay the change in the microstructure caused by the use under high loads and to prolong the rolling fatigue service life of a rolling bearing by using high carbon steel free from Mn content and small in oxygen content as steel for a rolling bearing. ;CONSTITUTION: As the stock for a rolling bearing, high carbon-high manganese steel contg., by weight, 0.5 to 1.5% C, 2.0 to 5.0% Mn and 0.0020% O and furthermore contg. one or ≥ two kinds among 0.05 t0 0.5% Si, 0.05 to 2.5% Cr, 0.05 to 0.5% Mo, 0.05 to l.0% Cu, 0.0005 to 0.01% B, 0.005 to 0.07% Al and 0.0005 to 0.012% N is used. By reducing the oxygen content, the content of oxide nonmetallic inclusions in the structure is reduced, and by increasing the Mn content, the delay of the change in the microstructure under repeated stress loads at the time of high load rolling is promoted, so that the steel for a high service life bearing excellent in rolling fatigue service life can be produced.;COPYRIGHT: (C)1994,JPO&Japio