Repair of HighTemperature RAM Coatings

The Phase I project developed an extensive database on electrical properties of candidate repair materials covering a wide range of thermal expansion coefficients from those of ceramic composites to those of superalloys. The Phase II project will develop, optimize and demonstrate unique, robust RAM repair materials that are chemically, mechanically, and electrically compatible with the state-of-the-art RAM coatings on current AF systems. Two applications will be addressed in separate, compartmentalized activities with Lockheed-Martin Aeronautical Systems and Pratt & Whitney. Using the database developed in Phase I and the requirements of the specific applications, candidate repair coatings will be selected and optimized to match the electrical properties of the targeted coatings. Experimental evaluations will include chemical compatibility with the baseline coatings and substrate materials, adherence, long term stability, and moisture and salt fog resistance. Evaluation will also include mechanical testing at ambient temperature before and after thermal cycling and electrical testing at ambient and elevated temperatures in air. A full-scale component or appropriate subcomponent demonstration will be conducted to validate the specific repair coatings developed for each application. Repair coating kits will be developed for each system to aid in the transfer of the repair coating technology to the end users.