Effect of SiC concentration in electrolyte on Ni-SiC composite coating properties

In the present study, a nickel sulphate bath containing SiC particles between 0.5 and 5.0 mu m has been used as the plating electrolyte to obtain Ni-SiC composites on copper surfaces with high hardness and wear resistance for using in antiwear applications such as dies, tools and working parts of automobiles. The influence of SiC concentration in the electrolyte on morphology, microhardness, friction coefficient and wear missing volume of coatings has been studied. The coatings were analysed with scanning electron microscopy as well as X-ray diffraction. The findings indicate that increasing the concentration of SiC particles in the Watts bath results in improving the microhardness of coatings and also decreasing the friction coefficient and wear missing volume. Increasing the presence of SiC particles not only decreases the grain size of Ni crystals but also changes the morphology and preference orientation of Ni crystals.