Hot corrosion behavior of LaTi2Al9O19 ceramic exposed to vanadium oxide at temperatures of 700-950 °C in air

Hot corrosion behavior of LaTi2Al9O19 ceramic exposed to V2O5 at 700-950 °C were investigated in order to better understand the corrosion resistance of LaTi2Al9O19 as a promising thermal barrier coating material. Results indicate that the degradation processes were significantly temperature dependent. At 700 °C, AlVO4, LaVO4 and TiO2 were the main corrosion products, while AlVO4 partially decomposed at 800 °C to form θ-Al2O3 and α-Al2O3. After exposure to 950 °C, V2O5 reacted with LaTi2Al9O19 to form LaVO4, α-Al2O3 and TiO2 as final corrosion products. The hot corrosion mechanisms were further discussed based on the phase diagrams of V2O5-Al2O3, V2O5-La2O3 and V2O5-TiO2 systems.