Abstract
Impedance based coating degradation, wetness, and cumulative damage sensors were deployed in several US Marine Corps bases. The sensors were placed inside dehumidified storage buildings and on ground vehicles stored outdoors to monitor the performance of corrosion preventive compounds (CPCs), and the severity of the environment as a function of time. The sensors were able to record coating integrity information real-time, and transmit this information remotely from a set of readers and base stations to a web-based portal for convenient monitoring and analysis. The sensor data were in agreement with visual observation of the sensor surface. The sensor information indicated vast differences in corrosivity depending on location, environment/seasonal conditions, storage location and location on vehicle. The least severe condition monitored was the dehumidified storage in Camp Lejeune, where the assets were protected from precipitation and condensation, and the relative humidity levels did not exceed 60%. The most severe conditions were found on vehicles stored on-lot, where coatings applied to boldly exposed surfaces were completely degraded and exposed elements were severely corroded. The CPCs were, however, effective in case of crevices, even under the most severe environmental conditions. In this paper, the results of the 2-year program are summarized.
