Investigation of Oxidation Properties of YSZ with Al2O3/YAG Composite Thermal Barrier Coating

In order to investigate the oxidation properties of YSZ with Al2O3/YAG composite thermal barrier coatings, Al2O3/YAG powder was synthesized by sol-gel method. 15, 30 and 45wt% of Al2O3/YAG were mixed with YSZ and labeled as YS85٫YS70 and YS55 respectively. Composite TBCS were melted by plasma spray method on a substrate (IN738-LC). Cyclic oxidation test at 1050○C for 200h and weight changes revealed that the oxidation resistance was increased in YS85 and YS70 and the thickness of thermally grown oxide was decreased and in YS55 by increasing the thermal stresses, the oxidation resistance was decreased and the thickness of the thermally grown oxide layer was increased.