Thin-Film, Ceramic Thermocouple Sensors Fabricated by Enhanced Plasma Deposition and Shadow-Mask Patterning

The U.S. Navy desires non-intrusive, conformally-coated sensors on stationary and rotating turbine-engine components to measure temperature, pressure, and strain. These thin-film sensors must be durable to survive the harsh engine operating environment (vibration, thermal-cycling/oxidation). Engineered Coatings, Inc. (ECI) and Southwest Research Institute (SwRI), propose to continue our work in Phase I to initially optimize the substrate and deposition conditions to achieve high-quality, low-defect alumina dielectric. Next, we will deposit nanostructured nitride and noble-metal thermocouple sensor legs using shadow-masking. The multilayer (ML) sensor will be finished with an encapsulating layer of alumina and topped with an erosion and corrosion-resistant protective layer. This ML sensor system will also be demonstrated on a curved blade using conforming shadow masks. Characterization will include microstructure, thermoelectric performance, and survival to thermal cycling/oxidation. Finally, the sensor system will be tested in a burner or engine rig to simulate the thermo-mechanical environment of turbine engine operation. In the Phase II option, we will demonstrate the reproducibility of sensor fabrication on curved blade surfaces and expose coated-blades in the burner or engine rig. A preliminary Materials and Process specification will be updated for the best deposition parameters and materials and a technology integration plan will be developed.