| 摘要 |
<p>An outer ring 6a for a shell-type radial needle bearing having a cylindrical shape with a bottom is achieved for which fatigue life of the bottom plate section 9a and the continuous section between the bottom plate section 9a and the cylindrical section 8a is improved, as well as the anti-corrosion characteristic of the outer ring 6a is improved and the outer ring 6a can be prevented from coming out of the bearing without an increase in cost. After obtaining an intermediate raw material 35 having a cylindrical section and a bottom plate section from a metal raw material, shot peening is performed on the intermediate material 35 to create residual compressive stress in the surface and surface layer section on the outer surface side of the cylindrical section 8a and the bottom plate section 9a such that the residual compressive stress in the surface layer section on the outer surface side is greater than the in the surface layer section on the inner surface side, and from the surface to a depth of 0.03 mm is 700 MPa to 1600 MPa.</p> |
