Electrodeposition of Ni-SiC nanocomposite coatings based on the surface charge determination of SiC nanoparticles

The point of zero charge of SiC nanoparticles was determined by means of standard salt addition method to select the surface-modification surfactants for SiC nanoparticles, while the nanostructured Ni-SiC composite film has been fabricated by dc electroplating technique based on the traditional composite electroplating technique and a few of nano-SiC particle predecessors. The results showed that SiC nanoparticles are negatively charged in the solutions with the pH value from 2 to 13, and the nano-SiC predecessors dispersed within the Ni-SiC composite film uniformly. The results also showed that the engulfed SiC nanoparticles increase the cathodic polarization during nickel electroplating, and stop the growth and congregation of existing nickel crystalline grains mechanically and accelerate simultaneously the nucleation rate of new nickel grains.