Abstract
In the previous study, the rolling contact fatigue life of case-hardened steel was improved by the cavitating jet in water with an injection pressure of 20 MPa. In this study, the cavitation peening apparatus with a maximum injection pressure of 35 MPa was designed and manufactured, and the optimum cavitation peening condition was determined quantitatively. From the result of the erosion tests, the peening intensity of the cavitating jet in water with an injection pressure of 35 MPa was larger than that of 20 MPa. In addition, the compressive residual stress of stainless steel became the largest by the cavitation peening using the nozzle geometry induced the maximum mass loss in the erosion tests. In the rolling contact fatigue tests, the rolling contact fatigue life of case-hardened steel was improved by the cavitating jet in water with an injection pressure of 35 MPa. However, the cavitating jet in water with an injection pressure of 35 MPa was inferior to that of 20 MPa in the rolling contact fatigue life of case-hardened steel. The reasons for this include that the surface roughness of case-hardened steel was increased by the cavitation peening with too long processing time.
