The Influence of Pulse Plating Parameters on the Structure and Corrosion Behavior of Ni-W-TiC Nanocomposite Coatings

In this study, Ni-W-TiC nanocomposite coatings were fabricated successfully on low-carbon steel via electrodeposition. The effect of duty cycle, frequency, current type (pulse or direct current), and the presence of TiC nanoparticles on the microstructure, composition, and electrochemical behavior were investigated. Scanning electron microscope, energy-dispersive spectroscopy, x-ray diffraction technique (XRD), polarization, and electrochemical impedance spectroscopy were used to characterize and evaluate the prepared coatings. Based on the XRD spectra of the different coatings, altering the plating parameters does not affect the phase structure, and the main phase of the coatings was Ni(W) solid solution. The results revealed that the optimal conditions in terms of the highest corrosion resistance were achieved under the pulse current with a duty cycle of 80%, pulse frequency of 1000 Hz, an average current density of 10 A/dm2, and TiC nanoparticle concentration of 5 g/L. The presence of TiC nanoparticles in the Ni-W alloy coating caused the morphology to change from cauliflower to turtle-shell and increased the coating thickness. The amount of TiC nanoparticles incorporated into the coating produced under the optimal condition was 3.5 wt.%, which plays an important role in the enhancement of the electrochemical behavior of the nanocomposite coating.