A Multifunctional Material Based on ZrC Modification Enhances the Mechanical Properties and Corrosion Resistance of Ni–W–P Alloy Coatings

Zirconium carbide (ZrC) is widely recognized for its exceptional hardness and thermal stability, making it a promising candidate for advanced coating applications. In this study, a novel PDA@ZrC-CeO₂ (PC@ZrC) composite material was prepared to enhance the corrosion resistance of the coating system. ZrC was modified with polydopamine (PDA) to improve its compatibility with the system. Subsequently, cerium oxide with a corrosion-inhibiting effect was introduced to form a multifunctional composite material. This composite material was integrated into the coating system using a simple deposition method. The effects of the composite on the surface morphology, phase structure, mechanical properties, and corrosion resistance of the Ni–W–P coating were investigated. The results show that Ni–W–P/PC@ZrC coating surfaces are dense and uniform among all the composite coatings, with no obvious defects. The average coefficient of friction is reduced by 30.3% compared with the pure coating, and the impedance value is nearly three times that of the pure coating. This is because the excellent dispersibility of PC@ZrC enables it to be evenly dispersed in the coating and fill the defects, giving the Ni–W–P/PC@ZrC coating excellent mechanical properties and corrosion resistance. The dual protection effect of PDA and cerium oxide at the same time gives Ni–W–P/PC@ZrC coating excellent long-term corrosion resistance.