Environmental barrier coatings (EBCs) are used to protect silicon carbide (SiC) components in gas turbine engines by inhibiting their surface reactions with water vapor and molten calcium-magnesium-alumino-silicates (CMAS). In this study, ytterbium monosilicate (Yb2SiO5) and mullite (3Al2O3.2SiO2) powders were synthesized and mixed with a specific content (mullite-12wt.%Yb2SiO5) as an EBC. The hot corrosion performance of the composite samples was investigated at 1300 °C for various durations in contact with molten CMAS powder. Phase analysis of the synthesized powders and hot-corroded specimens was characterized using the X-ray diffraction (XRD) technique. A scanning electron microscope (SEM) equipped with an energy-dispersive spectrometer (EDS) was used to study the morphology and chemical composi-tion of phases formed in the hot-corroded samples. The results showed that as the exposure time increased up to 48 h, the rate of reaction-layer growth significantly decreased, indicating enhanced substrate protection at high temperatures. Additionally, the formation of resistant phases, such as Yb₃Al₅O₁₂ and anorthite, during the reaction leads to an improvement in coating performance. These findings highlight the potential of Yb₂SiO₅-based EBCs for advanced gas turbine applications.

Keywords