Hot-corrosion behavior of a La2Ce2O7/YSZ thermal barrier coating exposed to Na2SO4+V2O5 or V2O5 salt at 900 °C

La2Ce2O7 (LC) has been considered as one of the promising thermal barrier coating (TBC) candidates for operating above 1250 °C. In this work, a LC/yttria stabilized zirconia (YSZ) double ceramic layer TBC was produced by electron beam physical vapor deposition (EB-PVD). Hot-corrosion behavior of the LC/YSZ TBC exposed to Na2SO4+V2O5 or V2O5 salt at 900 °C was investigated. After hot corrosion in Na2SO4+V2O5 salt for 4 h, a porous layer mainly composed of (La0.75Ce0.25)VO4 and CeO2 was formed on the LC layer. In V2O5 salt, the molten salt directly reacted with La2Ce2O7 solid solution, leading to the formation of (Ce0.5La0.5)VO4. The hot corrosion mechanisms of the LC/YSZ TBC in the two molten salts were discussed.