Paper Title
Degredation of YSZ, YSZ+Al2o3, CSZ and C-YSZ+Al2o3 TBCS After Thermal Cycle Tests

Abstract
In this study, ceriadoped YSZ(CSZ, 25 % CeO2 - 2.5 % Y2O3 - ZrO2 in weight) coatings are compared to commercial YSZ in terms of their mechanical and thermo mechanical properties. Also the effects of alumina additive on the pores, thermal cycle properties, bonding strength, and microstructure in ceramic coating are studied. Ceramic coat is produced by atmospheric plasma spray method while bond coat is produced by high velocity oxygen fuel method. While thickness of bond coat is 75 � 10 �m, thicknesses of YSZ, CSZ, YA, and CA ceramic coat is measured as 126, 135, 156, and 213 �m respectively. It has been observed that alumina additive decreased the porosity level in the coating significantly. Thermal cycle lifetime of YSZ, YA (YSZ+ Al2O3), CSZ and CA (CSZ+ Al2O3) coatings are 432, 416, 450, and 430 respectively. Al2O3 additive lowers the thermal cycle lifetime of coatings. It is also noticed that thermal cycle lifetime of CSZ coating is better than that of YSZ coating. Keywords- Aluminium Oxide, Plasma Spray, Thermal Barrier Coatings, Thermal Cycle, Cerium-Yttria-Zirconia,