| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a long-life rolling bearing hardly causing dimensional variation even when used in a high-temperature environment in an engine compartment of an automobile. <P>SOLUTION: A ball bearing 1 incorporated in an idling stop system is provided with an inner ring 2, an outer ring 3, two-line balls 4 and a cage 5. The ball 4 is made of SUJ3 specified by Japanese Industrial Standards, and subjected to tempering at 230-380°C after being subjected to carbonitriding quenching. Thereby, the average residual austenite quantity and hardness of the ball 4 are set not larger than 6 vol.% and not smaller than HRC57, respectively, wherein the area ratio of Si-Mn-based nitride formed on the surface thereof is set not smaller than 1.0%. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
