Research on the Synergistic Enhancement of Corrosion Resistance and Wear Resistance of Ni–W–B-Based Coatings by Nano CeO2 and PDA Functionalized VC

Abstract

Metal-based composite coatings have been widely studied for their excellent properties. In order to improve the properties of nickel tungsten boron (Ni–W–B) matrix, Ni–W–B/PC coatings were prepared by electrodeposition in the presence of polydopamine functionalized VC (P–VC) and cerium oxide (CeO₂) nanoparticles. The effect of cerium oxide content in the nanomaterials on the properties of Ni–W–B coatings was investigated. The results showed that the prepared coatings were dense, uniform, and crack-free, and the best performance was achieved at a cerium oxide content of 2 g/L. The addition of CeO₂ nanoparticles can fill the tiny defects in the coating and optimize the coating structure. The addition of these two materials refines the size of the coating grains. In terms of coating performance, the corrosion resistance of the composite coating was enhanced with the addition of CeO₂ at a certain P–VC concentration, and the total impedance of the composite coating was 24,030 Ω·cm², which was 4.8 times higher than that of the Ni–W–B coating and 1.7 times higher than that of the Ni–W–B/P–VC coating. In addition, the hardness of the Ni–W–B/PC-2 composite coating reached 1033.93 HV at a CeO₂ content of 2 g/L. The wear resistance of this composite coating was also optimized. Compared with the Ni–W–B/P–VC composite coating, the average coefficient of friction was reduced by 8.8%, and the wear resistance of the composite coating was further improved, which was attributed to the synergistic effect of the two materials. Moreover, the Ni–W–B/PC film has excellent hardness and corrosion resistance, which is promising for the application in harsh environments.