ROLLING CONTACT PART, ROLLING BEARING, UNIVERSAL JOINT, AND METHODS FOR MANUFACTURING THEM

摘要

PROBLEM TO BE SOLVED: To provide a rolling contact part which has characteristics equal to or more than those of a part made from SCM 420 while adopting a material free from Mo, and a rolling bearing.SOLUTION: An outer ring 11, an inner ring 12, and a ball 13 are formed from a steel containing 0.15 mass% or more and 0.25 mass% or less of carbon; 0.45 mass% or more and 0.55 mass% or less of silicon; 1.05 mass% or more and 1.15 mass% or less of manganese; and 1.40 mass% or more and 1.50 mass% or less of chromium, with the balance being iron and impurities respectively, and the surfaces thereof respectively have an outer ring rolling surface 11A, an inner ring rolling surface 12A and a ball contact surface 13A to make rolling contact with other members. An outer ring carburized layer 11B, an inner ring carburized layer 12B and a ball carburized layer 13B are formed respectively so as to include the outer ring rolling surface 11A, inner ring rolling surface 12A and ball contact surface 13A.