Impact of calcium zirconate nanoparticles on the mechanical and anti-corrosion properties of Ni-P coatings

Nickel-based coatings are one of the novel strategies adopted for the corrosion protection of metallic substrates. In this study, the effect of introducing and increasing the concentration of calcium zirconate nanoparticles (CZONPs) on the nickel-phosphorus (Ni-P) matrix has been investigated. Conventional electroless deposition technique has been adopted to develop Ni-P-CZONPs nanocomposite coatings. XRD spectra reveal the amorphous nature of all the coatings. XPS results prove the inertness and successful incorporation of CZONPs. SEM micrograph displays a significant shift of morphology from columnar to well-defined nodular structure. AFM results indicate an increase in the surface roughness of the nanocomposite coating. Moreover, mechanical analysis suggests an improvement due to the dispersion hardening effect provided by the stiff CZONPs. Furthermore, electrochemical assessment proves an enhanced corrosion resistance because of a reduction in the active area and blocking of the pathway of corrosion species by inert CZONPs. The most promising results were obtained at 0.75 g/L of CZONPs incorporated nanocomposite coating. However, agglomeration of CZONPs was noticed for 1.0 g/L of CZONPs, resulting in decreased mechanical and corrosion properties of nanocomposite coatings. CZONPs reinforced Ni-P-based nanocomposite coatings present an appreciable option for attention in several industries that require enhanced mechanical properties and superior corrosion resistance.