Thermochemical reaction behavior between Y2O3 and calcium-magnesium-aluminosilicate (CMAS) at elevated temperature

The thermochemical reaction behaviors between Y 2 O 3 and calcium-magnesium-aluminosilicate (CMAS) at 1250 °C∼1400 °C were investigated. A continuous-dense reaction layer mainly composed of Y-apatite phase quickly forms within 15 min, and its slow increasing thickness depends on the molten CMAS infiltration along the Y-apatite grain boundaries, the dissolution of the Y-apatite phase into the melt, the inhibiting effect on the CMAS penetration, and the reaction time and temperature. The CMAS crystallization occurs due to the change of chemical composition and the formation of other reaction products. The dense reaction layer shows good resistance to the molten CMAS infiltration.