Abstract:

Ceramic thermal barrier coatings （TBCs） have been increasingly used to extend the durability of aircraft gas turbine engine. This not only increases component lifetime, but also allows higher engine temperatures and therefore better efficiency. The TBCs structure has been developed from the conventional two layer structure to a gradient structure, which provided much better thermal cycle life than the former one. Compared with the plasma spray technique, the electron beam physical vapor deposition （EB\|PVD） has led to the incorporation of very durable coatings on the most demanding rotating turbine components. The optimal chemical composition of the ceramic top coat has been determined to be 6wt%⁸wt%Y 2O 3 stabilized ZrO 2（YSZ）; however, more temperature resistant and more durable ceramic coating materials are still required for the future applications. The bond coat material NiCoCrAlY with more Cr and less Al content can take account of advantages for both mechanical and chemical properties of the coatings.

Key words: TBCs, ZrO2, gas turbine