Calcium magnesium aluminosilicate (CMAS) corrosion behaviors of apatite Ca2La8(SiO4)6O2 thermal barrier coating material

The calcium magnesium aluminosilicate (CMAS) attack is becoming a critical obstacle to the application of thermal barrier coatings (TBCs). In this work, we prove that Ca2La8(SiO4)6O2 is an effective TBCs material for resisting CMAS attack, and investigates its CMAS corrosion behaviors. The results indicate that no evidence of chemical reactions was found between CMAS and Ca2La8(SiO4)6O2 heat-treated at 1300 °C and 1500 °C. The corrosion of apatite by CMAS occurs via dissolution and re-precipitation processes. At 1300 °C, the apatite Ca2La8(SiO4)6O2 substrates have little evidence of damage. Moreover, the apatite can also effectively block the infiltration of CMAS up to 1500 °C.