Surface Properties and Cavitation Erosion Resistance of Cast Iron Subjected to Laser Cavitation Treatment

Laser cavitation is a novel surface modification technology using the impact of bubble collapse and laser-induced plasma to induce plastic deformation and produce compressive residual stress on material surfaces. The effects of laser cavitation on surface properties and the cavitation erosion resistance of cast iron were studied. In this work, three-dimensional morphology and residual stress distribution of the laser cavitation area under different laser parameters was obtained, the variation regularities of the topographic range and impact depth of the affected area was discussed, and the weight loss rate of cast iron under different defocusing amounts was studied. It was found that laser cavitation can effectively improve the anti-cavitation erosion property of the cast iron surface, and the optimal value was reached when the defocusing amount was H = 1 mm. Combined with the various defocusing amounts and the variation trend of the weight loss rate of cavitation erosion, the cavitation erosion time corresponding to each stage of the cast iron (incubation, rise, decay, and stability) was obtained.