Effect of microstructure on the solid particle erosion properties of Ni plating

The effect of microstructure on erosion resistance of nickel plating was investigated in this study. Two electrode nickel plating processes, one with conventional nickel sulfamate electrolyte and the other with carbon nanotubes (CNTs) dispersed in the electrolyte, at various pulse frequencies were used to generate surface depositions of different microstructures. The samples were subjected to microstructural evaluations and mechanical property testing for microhardness and elastic modulus. Subsequently, erosion tests were conducted to evaluate the material's erosion resistance under various plating conditions. It was found that both changes in pulse frequency and the addition of CNTs resulted in grain size refinement and surface morphology modification. Microhardness of the plating was observed to increase with the pulse frequency in the absence of CNTs. Erosion resistance increased with grain refinement initially due to the surface hardness increase but this effect subsided as the thickness of the deposition approached that of the plastic deformation layer caused by the erodent.