| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a retainer for steel bearing, which is hardly run out of oil pressure and has good lubricity by forming a nitride layer densely, evenly and sufficiently on the surface thereof. SOLUTION: A retainer 1 is provided with a rolling element held in a pocket P between the outer peripheral surface of an inner ring 4 of a bearing A and the inner peripheral surface of an outer ring 5, and the inner and outer rings are supported in such a manner as to relatively rotate to form the bearing A. The retainer 1 has a nitride layer N where nitride mainly composed of Fe3 N is laminated densely and evenly with the average particle diameter of 1μm or less on the whole surface of a ring plate. The nitride layer N has surface roughness smaller than that of the conventional Tufftride processed article, and is considerably increased in smoothness. Further, as cracks are little caused, so that retaining capability for lubricating oil on the outermost surface of the nitride layer N is good and seizure-resistance is improved. Further there is no possibility of increasing friction in the nitride layer N so that oil film hardly runs out of and further seizure can be hardly caused.</p> |
