Characterization of the Cr-C/Si3N4 Composite Coatings Electroplated from a Trivalent Chromium Bath

Cr-C/Si3N4 composite coatings are obtained by electrodeposition under DC conditions from a trivalent chromium plating bath containing suspended Si3N4 nanoparticles. The influences of plating parameters including Si3N4 concentration in the plating bath and current density on the coating composition, deposition rate, morphology, surface roughness, micro-hardness and wear behavior of electrodeposited Cr-C/Si3N4 composite coatings are evaluated and compared with that of electrodeposited Cr-C coating. Our study reveals that Si3N4 particles can be successfully codeposited and uniformed distributed in the electrodeposited Cr-C matrix. The maximum level of incorporation of Si3N4 particles, about 17.22 vol%, is obtained at a bath loading of 5 g L-1 and at a current density of 20 A dm(-2). Due to enhanced dispersion strengthening effect, the incorporation of Si3N4 particles increases the microhardness of the coatings and significantly increases the wear resistance of the coatings. (C) 2016 Elsevier Ltd. All rights reserved.