This paper deals with the development of a new synthesis technique for functional materials such as Yttria Stabilized Zirconia (YSZ) in the field of thermal barrier coatings. Currently, Thermal Barrier Coatings (TBCs) are manufactured by dry route technologies (EB-PVD or plasma spray) but such methods are directional and often require costly investments and complex operations. For these applications, the sol-gel route, a non directional method, is developed, to process, by suitable chemical modifications, nanocrystalline materials with a controlled morphology. The main advantage of this method is to decrease the crystallization temperature, much lower than the conventional processes, allowing the synthesis of reactive substituted zirconia powders with nanometric particles size. In this study, several suitable architectures for thermal barrier coatings have been achieved in order to show that this process is appropriate for repairing damaged TBC compared to conventional processes. The next step is to investigate spallation mechanisms and overall TBC durability by cyclic oxidation. Preliminary results are promising and research will be develop further to optimize both processing and cyclic oxidation behavior.
Optimized sol–gel thermal barrier coatings for long-term cyclic oxidation life
