Effect of Pulse Electroplating Parameters on the Deposition of Reinforcing Particles in Ni-W/CeO2 Composite Coating

Recently, nickel-tungsten (Ni-W) coatings have been investigated by many researchers as a corrosion-resistant, wear-resistant, and high-hardness layer. However, reinforcing particles is also used to form composite and improve the performance of these coatings. Therefore, in this research work, Ni-W composite coating reinforced with CeO2 particles was formed by electroplating method with pulse current on pure copper metal. The microstructure, chemical composition, and thickness of the applied coating were investigated using field emission scanning electron microscope (FESEM). X-ray diffraction (XRD) was used to determine the phases formed in the applied coating. The effect of the parameters of the pulse plating process, including duty cycle, frequency, and waveform was investigated on the co-precipitation of reinforcing particles in the Ni-W matrix. The results showed that increasing duty cycle up to 70%, increasing the frequency up to 100 Hz, and using pulsed current with a square wave shape caused more particles to deposit in the coating. Under these optimal conditions, the composite coating was formed with uniform distribution of reinforcing particles, uniform thickness, and very good adhesion to the substrate.