Electrochemical properties during film degradation of coated steel

摘要

Organic coatings are widely used in the steel structures of power transmission and distribution systems to protect against corrosion. Early and accurate detection of coating degradation is clearly of critical importance. We investigated two methods for evaluating coating degradation-the alternating current (AC) impedance method and the current-interrupt (Cl) method-by exposing coated steel specimens to either long-term atmospheric exposure or shorter-term salt-water immersion, and then measuring their electrochemical behavior. We also analyzed coating degradation by x-ray probe microanalysis.