Preparation and resistance to CMAS corrosion of Y2O3-SiO2 binary ceramic materials

The corrosion caused by air sediments comprising CaO-MgO-Al 2 O 3 -SiO 2 (CMAS) poses a notable challenge to thermal/environmental barrier coatings as engine service temperatures continue to rise. In this study, three types of Y 2 O 3 -SiO 2 binary compound ceramic bulks—Y 2 SiO 5 , Y 2 SiO 5 -Y 2 Si 2 O 7 and Y 2 Si 2 O 7 —with molar ratios of Y 2 O 3 :SiO 2 of 1:1, 1:1.5, and 1:2, respectively, were prepared and subjected to CMAS corrosion at 1250 °C and 1350 °C for durations ranging from 1 to 10 h. The corrosion products and cross-sectional morphologies of the samples were characterized using X-ray diffraction and scanning electron microscope. The results demonstrate that the material composition determines its CMAS corrosion behavior. Y 2 SiO 5 , with higher Y 2 O 3 content, consumes more CaO to form Ca 2 Y 8 (SiO 4 ) 6 O 2 , thereby reducing the CaO content and increasing the viscosity of the residual CMAS melt. This process inhibits further CMAS penetration. The findings highlight a novel strategy to improve CMAS corrosion resistance by modifying the CMAS composition and reducing its penetration capability.