Patent ID: 7776453
Filing Date: 2010-08-17
Classification: B60B,C21D,C22C,F16C,F16D,Y10T

Abstract:
1. A machine element comprising an outer member, an inner member and rolling elements arranged in rolling grooves formed on said outer member and said inner member, respectively, wherein at least one of parts constituting said machine element is formed of steel containing C of 0.45 to 0.70 mass %, Si of not less than 0.15 mass % and not more than 0.4 mass %, Mn of 0.1 mass % to 0.25 mass %, and at least one of V, Nb and Ti of not more than 0.3 mass % in total, and ferrite in a micro structure of a portion not subjected to surface hardening process has an area ratio of 15 to 30% and contains particulate ferrite.