Pulse electrodeposition of Ni/nano-SiC composite coatings: Effect of waveform, duty cycle and current density

Abstract

In this study, nano-sized SiC particles have been codeposited with nickel using an additive free sulfamate bath under pulsed direct current (PDC) and direct current (DC). In order to find the effect of current density, duty cycle (D.C.) and waveform on coating, coatings have been studied in terms of microstructure, microhardness and SiC-codeposition. The scanning electron microscope results shown that the grain microstructure of the coatings have significantly affected by the waveform and D.C. changing the waveform in order of square, sine and ramp and also decreasing the D.C. resulted in finer grain microstructure. The SiC codeposition has shown an optimum value of about 3.3 wt% at the D.C. value of 30%; it also shows a reasonable trend with changes in the waveform. Moreover, according to the microhardness results, the composite coatings with fine grain microstructure have shown a higher microhardness.