| 摘要 |
PURPOSE: To make a rolling part having oil film forming capacity stable even against an objective body a surface of which is not finished cleanly and improve even in rolling fatigue longevity by controlling a rolling surface of the rolling part on a specific surface layer part. CONSTITUTION: This is a rolling part with a large number of small dents independent from each other formed on a rolling surface by roughing the rolling surface of the rolling part made of a carbonitrided high carbon steel material by shot blasting and barrel finishing it. The minimum value of residual compression stress is 90MPa or more on a surface layer part from a surface of the rolling surface to depth of 100μm, a content rate of a residual austenite phase in the surface layer part is 8 capacity % or more, the maximum roughness Rmax of the rolling surface is 3μm or less, root mean square roughness RMS is 0.3μm or less, a value of S showing a distortion degree of a distribution curve of surface roughness is -3 or less and an opening area of a small dent is 5-20% by way of expressing it by an area rate against a whole surface area of the rolling surface.
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