Comparative Study of Plasma Sprayed Yittria and Ceria Stabilized Zirconia Properties

Thermal Barrier Coatings are subjected to spallation and destabilization due to hot corrosion.Recently, Ceria Stabilized Zirconia (CSZ)-based TBCs have been intensively investigated for the YSZreplacement because CSZ has a much lower thermal conductivity and a higher expected thermalexpansion coefficient than those of YSZ. In this research, Yttria stabilized zirconia (YSZ) andceria stabilized zirconia (ZrO2 25CeO2 2.5Y2O3) TBCs were fabricated, followed by hot corrosiontests with a Na2SO4+V2O5 salt at 1050 °C. The treated samples were characterized using XRD andSEM equipped with EDS. From studies on microscopic failure behavior, the formation of YVO4 crystalsand the amount of phase transformations of tetragonal ZrO2 to monoclinic lead to degradation ofcoatings. Results revealed that CSZ TBCs were better resistant to hot corrosion than YSZ TBCs. Theamount of YVO4 crystals and monoclinic ZrO2 in YSZ are much more than CSZ which leads soonerdegradation of YSZ than CSZ. The strength of the Adhesive coatings of the substrate was alsomeasured in this study.