CaO–MgO–Al2O3–SiO2 (CMAS) corrosion behaviour of LaMgAl11O19/GdPO4 thermal barrier coating materials.

CaO–MgO–Al 2 O 3 –SiO 2 (CMAS) corrosion poses serious hidden dangers for the application of thermal barrier coatings (TBCs). In this study, LaMgAl 11 O 19 (LMA) and GdPO 4 were mixed at molar ratios of 2:1, 1:1 and 1:2 to prepare LMA/GdPO 4 materials, and the CMAS corrosion behaviours of these materials were investigated at 1300°C–1500 °C for 20 h and 40 h. It was demonstrated that temperature was the main factor influencing the corrosion behaviours and products. The materials were damaged at 1300 °C by the crystallization of CMAS melts to form CaAl 2 Si 2 O 8. In contrast, the materials were corroded by CMAS melts via the reaction between CMAS and GdPO 4 at 1500 °C. These results indicate that the addition of GdPO 4 to LMA can improve the resistance of the LMA material to CMAS corrosion. [ABSTRACT FROM AUTHOR]