RACEWAY RING FOR ROLLER BEARING, MANUFACTURING METHOD OF RACEWAY RING FOR ROLLER BEARING, AND, NEEDLE-LIKE ROLLER BEARING

摘要

To provide a raceway ring for bearing capable of prolonging the lifetime of a roller bearing at low cost.SOLUTION: The present invention relates to a raceway ring for roller bearing comprising a flange part. The raceway ring for roller bearing also comprises: an inner layer part which consists of tempered martensite or sorbite and of which the Vickers hardness is equal to or higher than 450 HV and lower than 550 HV; and a surface layer part which encloses a periphery of the inner layer part as a whole and consists of tempered martensite. In the raceway ring for roller bearing, the surface layer part includes a raceway part including a raceway surface in rolling contact with a roller. The raceway part includes: a first raceway part of which the compression residual stress of the raceway surface is relatively high; and a second raceway part of which the compression residual stress of the raceway surface is lower in comparison with that of the first raceway part. The Vickers hardness of the raceway part of the second raceway part is equal to or higher than 700 HV and less than 800 HV. The raceway surface of the first raceway part is harder than the raceway surface of the second raceway and includes a portion in contact with at least one axial end of a rolling surface of the roller. The Vickers hardness of a flange surface in the flange part is equal to or higher than 450 HV and lower than 550 HV.SELECTED DRAWING: Figure 2