Preparation and corrosion assessment of electrodeposited Ni–SiC composite thin films

Abstract

Ni–SiC composite thin films were successfully prepared via direct-current (DC) and ultrasonic pulse-current (UPC) deposition. The morphologies, mechanical properties, and corrosion properties of the films were investigated via atomic force microscopy, X-ray diffraction (XRD), Vickers hardness test, scanning electron microscope (SEM), cyclic polarization, and gravimetric analysis. The results show that the Ni–SiC composite thin films synthesized via UPC deposition possess a compact and exiguous surface morphology. The XRD results indicate that the average grain diameters of Ni and SiC in the UPC-deposited thin film are 63.6 and 38.5nm, respectively. The maximum microhardness values for the DC- and UPC-deposited Ni–SiC composite thin films prepared are 871.7 and 924.3HV, respectively. In the corrosion tests, the UPC-deposited films have a higher corrosion resistance than those prepared by DC deposition with the same SiC content.