Correlation of Corrosion Severity on Epoxy Coating Induced by Laboratory Simulation Test and Real Seawater Immersion Test postprint

Abstract: Corrosion behavior of epoxy coating induced by immersion in real seawater as well as immersion in 3.5%NaCl solution and salt spray in laboratory was characterized by means of electrochemical impedance spectroscopy (EIS). Then the relationship between the electrochemical impedance (|Z |0.01 Hz) of the coating tested in the two laboratory environments and that in seawater immersion test were analyzed. It follows that the degree of corrosion severity of the above three test environments could be ranked as: 3.5%NaCl solution＜seawater immersion＜salt spray. The salt spray test exhibited c.a. 2.3 fold stronger corrosivity for the epoxy coating, or say c.a. 2.3 acceleration effect on the corrosion of epoxy coating in comparison with the real seawater corrosion.