Fabrication of electrodeposited Ni-P/ZrB₂ nanocomposite coatings with enhanced mechanical and corrosion properties

Corrosion presents a significant challenge in today's urbanized world, severely affecting industries such as oil and gas, automotive, aerospace and construction, where material integrity and strength are crucial for long-term performance. Nickel-based coatings provide a cost-effective solution by enhancing mechanical and electrochemical properties. In this study, novel Ni-P/ZrB₂ nanocomposite coatings were developed with varying concentrations of ZrB₂ nanoparticles (0.25, 0.50, 0.75, 1.00 g/L) on carbon steel by electrodeposition technique. The fabricated coatings were analyzed using various characterization techniques. In parallel, COMSOL simulation was studied to investigate the distribution of current density and Ni2+ species in Ni-P coating. Additionally, predicted coating thickness values were obtained, ranging from 5-8 μm near the center and 10-15 μm at the edges. The structural (XRD, SEM), compositional (EDX, XPS) and topographical (AFM) analysis revealed an amorphous structure and support the incorporation of ZrB₂ into the Ni-P matrix. Ni-P/0.75 g/L ZrB₂ nanocomposite coatings exhibited the highest improvement in microhardness (34%), wear resistance (52%) and corrosion protection efficiency (92%) as compared to the Ni-P coating. This increase can be attributed to the (a) dispersion hardening effect due to ZrB₂ (b) load-bearing capability (c) reduction in active sites and filling of micropores in Ni-P matrix. Erosion analysis at different impact angles confirms the improvement in erosive wear resistance with the addition of ZrB₂ nanoparticles. An improvement in hydrogen permeation barrier is also observed with increasing ZrB₂ concentration, 1.0 g/L reducing the hydrogen diffusion and penetration into the coating.