Processes and properties of environmental barrier coatings

Environmental barrier coatings (EBC) for Si based ceramic matrix composites (CMCs) will play an increasingly important role in next generation gas turbine engines. A high performance and highly durable EBCs system depends significantly on the coating process, microstructure and coating architecture design. In this work, various processes for the deposition of ytterbium silicates based coatings were evaluated. The relationship among processes, microstructure and coating properties will be discussed. High temperature coating durability was also evaluated and tested in steam environment.