Effect of Multi-Walled Carbon Nanotubes (MWCNTs) in Reducing the Corrosion Rate in Cr-MWCNTs Composite Coatings

Abstract

Carbon steel was coated with Cr-multi-walled carbon nanotube (MWCNTs) coatings via electrodeposition. In this article, the impact of a combination of MWCNTs into the chromium coating on the morphology of the coating surface and corrosion characteristics was inspected. The MWCNTs seem to be evenly distributed across the chromium layer, according to scanning electron microscopy (SEM). Electrochemical measurements were used to conduct corrosion tests on samples of MWCNTs– chromium composite coated and pure chromium coated samples in aqueous NaCl (3.5 wt.%). The outcomes demonstrated a considerable increase in the resistance of corrosion due to the inclusion of MWCNTs during the chromium deposition procedure. In addition, the mechanism of anti-corrosion of the composite coating is also presented. Using an electrolyte bath containing various concentrations of dispersed MWCNTs (0.5, 1, and 1.5 g/L), crack-free and compact coating of Cr-MWCNT composite were electrodeposited on the substrates of the mild steel. The potentiodynamic polarization technique was used to examine the coatings corrosion performance subjected to a 3.5 weight percent of NaCl medium. When compared to chromium coating, the Cr-MWCNT composite coating showed the lowest corrosion rate (1.045x108 mpy) compared to chromium coating (4.891x108 mpy).