Cavitation characteristics and properties of Ni-based claddings deposited by the plasma jet cladding process

Three kinds of Ni-based metal claddings (Ni46, Ni67, and Ni60/35WC) were deposited by the plasma jet cladding process. These cladding samples were then subject to cavitation erosion testing on the rotating disc cavitation test equipment. SEM, X-ray diffraction, micro hardness, and weight loss analysis were exploited to analyze the changes of the materials. The results showed the values of weight loss for all claddings were more than that of stainless steel 304. SEM images showed a large number of cracks occur and propagate under subsurface, for the existence of cavity and the other faults of structure, which significantly decreased the cavitation erosion resistance of the cladding materials, So the cavitation erosion is a typical fatigue failure process, Some new phases appeared and some old phases disappeared on the surface of the Ni60/35WC cladding after cavitation testing by X-ray diffraction. For Ni67 and Ni60/WC, the microhardness values of surface claddings became higher after cavitation and softer for Ni46.