Investigation of the influence of incidence angle on the process capability of water cavitation peening

Water cavitation peening (WCP), through the cavitation impact induced by the water jet process, has been applied to introduce the compressive residual stress in the surface layer of metallic materials. In the present study, five incidence angles (0°, 30°, 45°, 60°, and 90°) were adopted. The impact pressure induced by the bubble collapse was measured by a pressure measurement technique with pressure sensitive film. The residual stresses of a spring steel SAE 1070 plate specimen treated by WCP were determined through X-ray stress analysis. The results indicated that the impact pressure and residual stress obtained at various incidence angles were almost equal to each other in the effective process area. It implied that the process capability of WCP was almost isotropic. Moreover, such potential of WCP was also applied to a carburizing-quenched helical gear, and the high and uniform compressive residual stress was simultaneously introduced in the surface and bottom of gear tooth. It indicated that, compared with the conventional shot peening and laser shock peening, WCP was more effective to the metallic components with the complicated shape.