Effect of Graphene Content on Composition and Corrosion Resistance of Co-Ni-Graphene Composite Coating

Abstract

The nanocrystalline CO-Ni-graphene composite coating were successfully fabricated onto the mild steel substrate by electrochemical co-deposition technique. The coating was prepared by changing the amount of added graphene at the bath temperature of 50°C, PH value of 4 and current density of 2A/dm2. Scanning electron microscopy (SEM), Energy dispersive spectroscopy (EDS) and X-ray diffractometer (XRD) were used to analyze the surface morphology, composition and phase structure of the coating. The prepared composite coating was then subjected to an impedance map in a 3.5% NaCl solution by a VersaSTAT3 electrochemical analyzer. The results show that the surface morphology of the coating was coarsened with the increase of graphene content in the electrolyte. The corrosion rate of the coating in the 3.5% NaCl solution first decreased and then increased, and the corrosion rate was 0.1998mA/cm2 at a content of 1.0 g/L.