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

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.