Materials Chemistry and Physics, Vol.229, 495-507, 2019
Electrodeposition of Ni-W/ZrO2 nanocrystalline film reinforced by CeO2 nanoparticles: Structure, surface properties and corrosion resistance
To enhance the performance of nickel-tungsten (Ni-W) matrix, Ni-W/ZrO2-CeO2 nanocrystalline films have been fabricated by electrodeposition in the presence of zirconia (ZrO2) and ceria (CeO2) nanoparticles. The influences of process parameters on microstructural, surface properties and corrosion resistance of the nano crystalline films were examined. Studies indicated that the fabricated films are dense, homogeneous and without cracks, comprising 23.7-28.7 wt% W, 3.9-4.9 wt% ZrO2 and 0.45-0.68 wt% CeO2. The film prepared at average current density of 6 A dm(-2), duty cycle (r) of 70% contains the highest content of ZrO2, CeO2 nanoparticles with the finer structure. The average roughness (R-a) is 79.1 nm for film formed at 2 A dm(-2). The growth rate of the film is about 0.48-0.53 mu m/min at I-av = 4 A dm(-2) and r = 50%. The hardness first increases and then decreases with the maximum value at r = 70%, I-av = 6 A dm(-2) and deposition time (t) of 40 min, respectively. Energy disperse spectroscopy (EDS) mapping, transmission electron microscope (TEM) and cross-sectional images illustrated that the ZrO2 and CeO2 particles had been homogeneously incorporated in the film. The electrochemical measurements illustrate that the optimal corrosion resistance of Ni-W/ZrO2-CeO2 film could be obtained at r = 70%, I-av = 6 A dm(-2) and t = 40 min. The incorporation of ZrO2-CeO2 in Ni-W film would enhance the anti-corrosion properties and hardness. Ni-W/ZrO2-CeO2 film owns superior hardness and excellent anti-corrosion properties, showing a broad application prospect in harsh environment.