Synthesis and properties of electroless Ni-P-HfC nanocomposite coatings

Abstract

This work reports the development and characterization of Ni–P coatings with varying concentrations of hafnium carbide nanoparticles (HCNPs). Novel Ni–P-HCNPs nanocomposite coatings were developed on the A36 carbon steel by an electroless deposition technique. The effect of an increasing amount of HCNPs (0.25 g/L, 0.50 g/L, 0.75 g/L, and 1.00 g/L) on structural, compositional, microstructural, topographical, electrochemical and mechanical properties of Ni–P coatings was investigated. The structural (XRD, FE-SEM) and compositional analyses (EDX, XPS) confirm the successful incorporation of HCNPs into the Ni–P matrix. It is further noticed that the quantity of HCNPs has a substantial impact on modifying the microstructural, surface, mechanical, and corrosion resistance properties of Ni–P-HCNPs nanocomposite coatings. A comparative analysis of the properties of developed coatings suggests that nanocomposite coatings containing 0.75 g/L HCNPs demonstrate the highest improvement in hardness (∼40%) and corrosion resistance (∼95%) when compared to the Ni–P coatings. The increase in hardness can be attributed to the dispersion hardening effect experienced due to the presence of HCNPs. The improvement in the corrosion resistance properties can be ascribed to the reduction in the active sites of the Ni–P matrix and the filling of the micro pores with HCNPs. The attractive properties of HCNPs nanocomposite coatings provide an appealing option for their application in various industries such as aerospace, automobile, electronic, and oil & gas industry.