The Use of Electrochemistry and Ellispsometry for Identifying and Evaluating Corrosion on Aircraft

This proposal focuses on the development of an in-situ atmospheric sensor capable of identifying and evaluating regions of corrosion occurring specifically on aircraft. The sensor is antiucipated to have an electrode applied on the coating of the test coupon. When this electrode and coupon are exposed to moisture, either by immersion or high humidity, the near de impedance of the coating-metal system decreases by one to two orders of magnitude. Electrochemical impedance spectroscopic (EIS) measurements using these test electrode sensors, a potentiostat and lock-in amplifier will be correlated with adhesion of the paint to the metal substrate and corresion of the substrate. Ellipsometry and X-Ray Photoelectron Spectroscopy will be used to quantitatively assess the de-adheion to the amount of corresion occurring. In this way, the sensor offers a quantitative measure of incipient corrosion unlike other corrosion monitors that simply measure the time of wetness or the corrosion rate of the sensor itself, or that require externam electrodes and a bulk electrolyte medium.