Abstract: The object of the present invention is to provide a method for shot peening by which a compressive residual stress that is higher than any achieved by the conventional method can be achieved while the thickness of the processed material that is scraped is suppressed. The method is characterized in that the shot materials are shot against the processed material that has the hardness of 750 HV or more that is calculated from equations (1) to (3) below. The shot materials have Vickers hardness that is higher than the hardness of the processed material by 50 HV to 250 HV. The thickness of the processed material that is to be scraped is suppressed to 5 ?m or less. HV(m)={f(C)?f(T,t)}(1??R/100)+400×?R/100??Equation (1) f(C)=?660C2+1373C+278??Equation (2) f(T,t)=0.

Abstract: The object of the present invention is to provide a method for shot peening by which a compressive residual stress that is higher than any achieved by the conventional method can be achieved while the thickness of the processed material that is scraped is suppressed. The method is characterized in that the shot materials are shot against the processed material that has the hardness of 750 HV or more that is calculated from equations (1) to (3) below. The shot materials have Vickers hardness that is higher than the hardness of the processed material by 50 HV to 250 HV. The thickness of the processed material that is to be scraped is suppressed to 5 ?m or less. HV(m)={f(C)?f(T,t)}(1??R/100)+400×?R/100??Equation (1) f(C)=?660C2+1373C+278??Equation (2) f(T,t)=0.

Abstract: A bearing mechanism eliminates the need for lubricating oil, is capable of generating enough radial dynamic pressure even in lower-speed regions, and yet can be easily surface-machined for the generation of radial dynamic pressure and manufactured with low cost. In at least either one of an outer circumferential surface 2a of a first member 2 or an inner circumferential surface 3a of a second member 3 (hereinafter, referred to as roughened surface), the two circumferential surfaces being opposed to each other with a bearing gap G therebetween, dot-like minute dips and bumps are formed dispersedly, by which the surface is roughened so that its center-line mean roughness is controlled within a range of 0.1 &mgr;m-1.0 &mgr;m.