BEARING STEEL EXHIBITING EXCELLENT MACHINABILITY AFTER SPHEROIDIZING ANNEALING AND EXCELLENT RESISTANCE TO HYDROGEN FATIGUE AFTER QUENCHING/TEMPERING

摘要

Provided is bearing steel excellent in workability after spheroidizing-annealing and in hydrogen fatigue resistance property after quenching and tempering. The bearing steel has a chemical composition containing, by mass%: 0.85 % to 1.10 % C; 0.30 % to 0.80 % Si; 0.90 % to 2.00 % Mn; 0.025 % or less P; 0.02 % or less S; 0.05 % or less Al; 1.8 % to 2.5 % Cr; 0.15 % to 0.4 % Mo; 0.0080 % or less N; and 0.0020 % or less O, which further contains more than 0.0015 % to 0.0050 % or less Sb, with the balance being Fe and incidental impurities, to thereby effectively suppress the generation of WEA even in environment where hydrogen penetrates into the steel, so as to improve the rolling contact fatigue life and also the workability such as cuttability and forgeability of the material.