Effect of Nano-Sic Particles on Properties of the Ni-Sic Gradient Composite Coating

Abstract

In this paper, Ni based gradient composite coatings containing micro- and nano-SiC particles was prepared by dipulse electrodepositing in watts nickel solution. The effect of nano-SiC added in the solution on the micro morphology, wear-and corrosion resistance of the coating was investigated. The results show that the grain size of Ni-SiC gradient composite coatings is fined when adding nano-SiC in electrolyte; the maximum microhardness of gradient coating is 553 HV, and the average coefficient of gradient coating with 0.41 are about 1.5 times and 4/5 than that of micro-SiC gradient composite coating; and shows the best corrosion resistance which the values of corrosion current density with 1.957×10^-7A.cm2 is about 1/10 than that of micro-SiC gradient composite coating.