Patent ID: 7396422

Claim:
A rolling bearing sized for use in a swing arm of a hard disk drive, the rolling bearing comprising a plurality of rolling elements provided between inner and outer rings, at least one of the inner and outer rings being formed of corrosion resistant bearing steel comprising carbon of 0.5 to 0.56 wt %, silicon of 1 wt % or less, manganese of 1 wt % or less, phosphorus of 0.03 wt % or less, sulfur of 0.01 wt % or less, chromium of 8.00 to 9.50 wt %, molybdenum of 0.15 to 0.50 wt %, copper of 0.30 to 0.7 wt %, titanium of 15 ppm or less, vanadium of 0.15 wt % or less, oxygen of 15 ppm or less, iron as remaining component and impurities inevitably incorporated thereinto, the corrosion resistant bearing steel containing eutectic carbides having a circle equivalent diameter with an average value of 0.2 to 1.6 μm, the eutectic carbides having an average area of 0.03 to 2 μm 2 and an area ratio of 2 to 7%, the corrosion resistant bearing steel having a hardness of HRC 58 to 62 by JIS, and containing a retained austenite of 6 volume % or less.