THERMAL BARRIER COATINGS FOR AIRBREATHING COMBUSTION SYSTEMS

With improvements in superalloy technology only modest increases in op erating temperatures for components of airbreathing propulsion systems can be achieved. The necessarily resulting augmentation of component cooling might require so much compressor bleed air that there would be a significant decay in the expected increase in engine efficiency. Th e need for advanced materials with the required properties led to the development of thermal barrier coating systems. The current status and future trends of thermal barrier coatings (TBCs) are reviewed with re gard to gas turbine applications. This includes the TBC deposition pro cess, the failure mechanisms and results of testing under service-like conditions.