Patent ID: 7413704
Filing Date: 2008-08-19
Classification: C21D,C22C,C23C,Y10S

Abstract:
1. A case hardening bearing steel having excellent toughness and an excellent rolling contact fatigue life in intermediate temperature comprising: C of 0.15 to 0.30 mass percent, Si of 0.5 to 2.0 mass percent, Mn of 0.3 to 2.0 mass percent, Cr of 1.75 to 2.5 mass percent, Mo of 0.3 to 1.0 mass percent, and O of not more than 0.0012 mass percent, in a range where (Si+Mo)≧1.0 mass percent is satisfied, and containing iron and inevitable impurities as remnants; the maximum size of oxide nonmetallic inclusions is not more than 12.5 μm when an examined area is 320 mm