2025 Volume 74 Issue 2 Pages 15-20
To monitor paint film degradation and corrosion under the paint film in real time in an atmospheric corrosion environment, we challenged to apply continuous two-point frequency impedance measurement. By using an ICM sensor coated with epoxy resin paint, it was possible to predict the behavior from the growth of paint film defects to the occurrence of rust spots. We confirmed that even if corrosion occurs at the paint film interface, the thick paint film slows down the occurrence of rust spots too. We were able to understand the effects of different corrosive environments, such as constant high humidity and repeated wet and dry conditions, on paint film degradation and corrosion at the paint film interface.