Novel Nano-Core–Shell Structure SiO2@Ni-Reinforced Ni-P-Based Amorphous Composite Coating

A Ni-P nanocomposite coating is one of the most widely applied corrosion- and wear-resistant coatings. However, the agglomeration of nanoparticles will reduce their performance. In this study, SiO2@Ni nanoparticles with a core–shell structure were first prepared by pre-plating, and then SiO2@Ni nanoparticles were introduced into Ni-P coating to achieve a Ni-P-SiO2@Ni composite coating. The results show that the existence of SiO2@Ni nanoparticles can significantly reduce the agglomeration of nanoparticles in the coating. Compared with Ni-P and Ni-P-SiO2 nanocomposite coatings, the Ni-P-SiO2@Ni composite coating exhibits improved corrosion and wear resistance and hydrogen barrier performance. In addition, the Ni-P-SiO2@Ni composite coating also has excellent mechanical properties, with a hardness of up to 340 HV and a bond strength of 15.8 MPa, presenting highly potential industrial applications. This work provides a novel design of protective coating with excellent anti-corrosion resistance and mechanical properties, which has a promising prospect in the development of anti-corrosion coatings for aluminum alloys.