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 post spheroidizing-annealing workability and in post quenching-tempering hydrogen fatigue resistance property. 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; 0.0020 % or less O; and 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.