Transcripción del resumen del autor. The protection of metallic structures by organic coatings has traditionally been as a barrier, reducing the transport of water, ions, and oxygen from the environment to the substrate. Organic coatings are also used as repositories for corrosion inhibitors, which passivate the substrate, and metallic particulates, which provide cathodic protection. Of the latter, Zn-rich primers are used universally for the protection of steel substrates with the zinc particles being sacrificially consumed while providing a mixed potential that mitigates the corrosion of the steel. Recently, Mg-rich primers have been developed for the protection of aluminum substrates, with a similar protection mechanism as that of Zn-rich primers. Real-time monitoring of a Mg-rich primer on an aluminum alloy 2024-T3 (UNS A92024) substrate, beneath a standard United States Air Force topcoat, was conducted, where coatings were subjected to ASTM B117 exposure. Monitoring was accomplished using embedded electrodes placed between the primer and topcoat. Electrochemical impedance spectroscopy and electrochemical noise method experiments were conducted to assess the performance of the primer in the aggressive salt spray environment. In situ results were compared with results of ex situ electrochemical experiments. Results associated with configurations with and without the substrate as the working electrode are presented to demonstrate the applicability of the embedded electrodes for real-time monitoring.

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