Influence of particle size and surfactants on uniformity and quantity of silicon carbide particles in electrodeposited nickel-silicon carbide coatings

The electrodeposition of nickel-silicon carbide coatings on a copper electrode was done by mixing SiC particles in the nickel electrodeposition solution. The influence of surfactants and silicon carbide particle size on uniformity and quantity of silicon carbide particles in nickel-silicon carbide composite coatings was investigated. It was found that particle size affects the nucleation overpotential, with 40 nm silicon carbide nanoparticles more effective in promoting nickel nucleation than 500 nm particles due to an increase in active nucleation sites. In terms of surfactants, anionic surfactant sodium dodecyl sulfate (SDS) produced better dispersion of 40 nm silicon carbide particles than cationic surfactant cetyltrimethyl ammonium bromide (CTAB), but little difference was found between the two when 500 nm silicon carbide particles were used. Thus, although the suspension of silicon carbide particles can be improved and their co-deposition can be promoted with a cationic surfactant CTAB, it is less effective than an anionic surfactant SDS in terms of surface finish.