Exploring transport properties and onset of corrosion in organic coated metals using an innovation sensor-based methodology supported by ORP-EIS

This study presents an innovative sensor-based methodology for the non-destructive, in-situ evaluation of transport properties of protective coatings, as well as detection of onset of corrosion at the coating-metal interface. This technique monitors capacitance changes induced by electrolyte diffusion through the coating. To validate this approach, Odd Random Phase Electrochemical Impedance Spectroscopy (ORP-EIS), as a powerful technique, was employed. In ORP-EIS technique proposed previously by our group, in addition to the effectively shortened measurement time, initial fast water-uptake and its diffusion coefficient can be studied using instantaneous impedance. Results obtained from the sensor-based method demonstrated strong correlation with ORP-EIS data, confirming the reliability and efficacy of the proposed technique. This innovative sensor approach offers a promising tool for in-situ monitoring of coating performance in corrosive environments.