| 摘要 |
PROBLEM TO BE SOLVED: To suppress the occurrence of a surface origin damage and also suppress the generation of a stamp flaw or frosting by using a bearing steel having a specified maximum grain size or less of a carbide in the surface layer and a specified surface hardness or more for either one of a race and a rolling body. SOLUTION: Since this rolling bearing has a surface hardness of HRC 60 or more, a high-temperature hardness equal to or higher than M50 can be provided. Since the maximum grain size of a carbide in the surface layer can be set to 8μm or less which is smaller than M50, the dropping-out of a carbide or the occurrence of a surface origin damage with the carbide as a stress collecting source can be prevented under a high-temperature condition causing the deterioration of lubricating characteristic is deteriorated or a condition causing the biting of foreign matter. Since the maximum grain size of the carbide can be set smaller than M50, a counter object can be prevented from being damaged even if the metal contact with the counter object is caused in rolling because of a poor lubricating characteristic, and a so-called stamp flaw or frosting can be prevented.
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