Cavitation erosion of 304 stainless steel induced by caviting water jet

Cavitation erosion of 304 stainless steel was studied by means of caviting water jet (CWJ) with varying stress and time. By tracking the surface morphology change with scanning electron microscope after the CWJ treatment, the process and mechanism of cavitation erosion were analyzed and the microstructure evolution of the surface and the relevant deformation mechanism were investigated as well. The results are as follows: according to the difference in damage rate and mechanism, the cavitation damage zone can be divided into jet impact zone, transition zone and turbulent zone from the center to the periphery, among them, the damage degree of jet impact zone was the worst, transition zone was the weakest. The damage of jet impact zone was accelerated by the jet pressure 35 MPa for 40 min, and it presented clear characteristics of fatigue damage, the initiation and propagation of fatigue crack in the area of slip band and grain boundary is one of the important reasons leading to the spalling damage; The twin layer of the transition zone and turbulent zone were thicker than that of the jet impact zone in the cross-sectional microstructure, and the thickness of the twin layer in turbulent zone was 140 μm; Under the conditions of this experiment, the main deformation mode of 304 stainless steel is slip deformation, the second is twin deformation. There are two kinds of mechanism of cavitation erosion induced by the cavitating water jet, one is fatigue failure under cyclic loading, the other is arc-shaped pit caused by plastic deformation, necking and spalling. © All right reserved.