Characterizations of Ni-CeO2 nanocomposite coating by interlaced jet electrodeposition

Abstract

The properties of conventional nickel coatings were improved by preparing Ni-CeO2 nanocomposite coatings by jet electrodeposition. On the basis of these results, a new method involving discontinuous cathode rotation and interlaced deposition was proposed. The effects of nanoparticle (NP) concentration and interlacing technology on the surface quality, NP content, and microstructure and corrosion resistance of the resulting composite coatings were investigated. The microstructure and surface morphology were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM), the corrosion resistance was tested by electrochemical workstation. The results showed that, adding an appropriate amount of CeO2 NPs, effectively improved coating surface quality and reduced defects, such as cellular bulges, micropores, and microcracks. The corrosion current density was reduced from 1.612 to 0.459 μA cm−2, compared to pure Ni, which indicated that corrosion resistance was clearly improved. With the introduction of interlacing, the coating NP content increased up to 4.76 wt %, higher than the 4.25 wt % of conventional jet electrodeposition. The resulting coating surfaces were more uniform and smooth, and the problem of coating quality deterioration in traditional jet electrodeposition because of excessive NP addition was somewhat improved. With interlaced deposition, the corrosion current density was further reduced to 0.349 μA cm−2, with the coating corrosion further enhanced.