Corrosion Resistance and Hydrogen Barrier Resistance of Nano-Al2O3 Doped Amorphous Ni–P Coating

Abstract

Aluminum oxide (Al₂O₃) exhibits robust self-healing properties and chemical stability, along with superior hydrogen resistance and corrosion resistance. Additionally, it can serve as a hard particulate component in various coatings. In this study, an amorphous Ni–P coating doped with Al₂O₃ nanoparticles was applied to a Q235 steel substrate using electrodeposition technique. The investigation focused on the influence of nano-Al₂O₃ dosage on the properties of the Ni–P composite plating. The findings indicate that the inclusion of Al₂O₃ nanoparticles significantly enhances the corrosion resistance, hydrogen resistance and wear resistance of the Ni–P coating. Specifically, for the Ni–P coating with the Al₂O₃ addition of 3 g/L (Ni–P–Al₂O₃-3 coating), the impedance value increased by 64.4%, while the corrosion current decreased by 58.7%. Furthermore, the Ni–P–Al₂O₃-3 coating demonstrated an extended hydrogen penetration time and a reduction in hydrogen diffusion coefficient by an order of magnitude compared with pure Ni–P coating.