Degradation of Two Anti-Corrosion and Anti-Fouling Coating Systems in Simulated Diurnal Cycling Immersion

The degradation process and the electrochemical behavior of two anti-corrosion anti-fouling coating systems (FW-1 FW-2) in a simulated diurnal cycling immersion environment (3.5% NaCl, 35 °C 12 h + 25 h) were investigated by impedance spectroscopy (EIS) technology. Combined with gloss, color difference, adhesion strength scanning electron microscopy (SEM) tests, micro morphologies variations performance parameters comparatively analyzed. results showed that 160 days immersion, hydrolysis FW-1 topcoat resin some pigments dissolved released, surface micro-morphology changes from rough to smooth, thereby increasing gloss. While, for FW-2 topcoat, occurrence pores tiny cracks an increase roughness decrease release copper ion particles antifouling has influence on color, manifesting as obvious rise difference coating. low-frequency (|Z|0.01 Hz) values both samples decreases slowly, presenting very good shielding carbon steel substrate. self-polishing no big effect whole system; protective system mainly depends integrity primer intermediate paint.