Preparation of a Ni–Mo–P–PCTFE nanocomposite coating and evaluation of its nano-tribological, mechanical and electrochemical performance

Abstract

In this study, the tribological, mechanical and electrochemical performances of electrodeposited nickel–molybdenum–phosphorus (Ni–Mo–P) coating containing polychlorotrifluoroethylene (PCTFE) nanoparticles were investigated. The nanocomposite coatings were deposited from potassium sodium tartrate containing electrolytes at four different concentrations of PCTFE (0, 4, 8 and 20 g L⁻¹). The surface morphology, chemical and phase compositions of the Ni–Mo–P/PCTFE coatings were investigated using field-emission scanning electron microscopy (FE-SEM), Energy Dispersive X-ray Analysis (EDAX) and X-ray Diffractometry (XRD), respectively. Corrosion behaviour of the coatings was examined using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Atomic force microscopy (AFM) was used to investigate the tribological properties of the surfaces and in addition, their water-repellency was determined. The results show that there is a significant enhancement in corrosion resistance with the incorporation of PCTFE particles into the Ni–Mo–P matrix. It was also observed that the addition of PCTFE in the Ni–Mo–P alloy matrix has resulted in a smoother surface with a low friction coefficient and excellent water repellency.