Machine part

摘要

Machine part is constituted with steel with the carbon content of 0.2% or more and reduced with the hydrogen content after hardening by a heat treatment to 0.04 ppm or less. Further, hardness after hardening by the heat treatment is made to Hv 450 or more. Since such a machine part is excellent in the super long life fatigue characteristics, it can be used suitably as a bearing ring or a rolling element of a rolling bearing.