Effect of Graphene on Corrosion Resistance of Low Zinc Epoxy Coatings Applied to Low-Carbon Steel

To reduce the consumption of zinc resources, it is necessary to reduce the zinc powder content of epoxy zinc-rich coatings. However, the reduced zinc powder content tends to reduce the degree of connectivity in the layer, which leads to a reduction in the corrosion resistance of the coating. The effective zinc powder content was also reduced. Therefore, it is important to increase the connection capacity of the zinc powder in the coating while reducing the amount of zinc powder. In this paper, an epoxy coating with low zinc content is prepared by using flake zinc powder instead of spherical zinc powder. It also uses graphene to connect zinc powder in the coating to increase the electrical conductivity of the zinc powder in the coating. This results in an increase in the protection of the coating determined, although the cathodic protection of the coating was not prolonged by the results of open-circuit potential and electrochemical impedance spectroscopy. In addition, when the zinc powder in the coating is cleanly consumed, the complex nature of corrosion product formed with graphene can increase the barrier resistance of the coating thereby increasing the corrosion resistance.