Anticorrosion Performance of Epoxy Resin Zn-Al Coating

Epoxy resin Zn-Al coatings with different aluminum content were prepared on the surface of Q235 steel. The corrosion resistance of the coatings was studied by Machu test, electrochemical test and infrared spectrum test. The results show that the epoxy resin Zn rich coating had the effect of cathodic protection due to zinc powders. When the epoxy resin Zn rich coating was added with a certain amount of flake aluminum powders (mass fraction of 4%-6%), the microporous defects and the barrier performance of the coating were improved. Flake aluminum powders enhanced the cathodic protection effect of zinc powders by improving the electrical continuity of zinc powders in the coating. The corrosion products generated by the reaction of the corrosive medium through coatings with zinc and aluminum had better corrosion resistance than those generated by the reaction of the corrosive medium with zinc alone.