Protective Performance of Waterborne Anti-Corrosion Coating in Simulated Marine Atmospheric Environment

A waterborne anti-corrosion coating system was prepared by spraying waterborne epoxy zinc-rich primer, waterborne epoxy micaceous iron intermediate paint and waterborne acrylic polyurethane topcoat on the surface of Q235 carbon steel. The corrosion resistance of the coating system in simulated marine atmospheric environment was systematically studied by cyclic salt spray test combined with adhesion and gloss test, electrochemical test and so on. The results show that the adhesion of the coating decreased gradually at the beginning of the cyclic salt spray test, and then the chang was not obvious. After 1 200 h cyclic salt spray test, the adhesion was still as high as 6 MPa, which could meet the Class I standard in the technical requirements. After 1 200 h test, the low-frequency impedance value of the coating was still as high as 10⁸ Ω·cm², indicating that the coating could provide excellent protection performance for power transmission and transformation equipment in marine climate.