Fabrication of Ytterbium Disilicate-based EBCs By Using Suspension Plasma Spray

Rare-earth disilicates, such as Yb₂Si₂O₇ and Y₂Si₂O₇, have been investigated as one of the candidate materials for environmental barrier coating (EBC) applications to protect silicon (Si)-based ceramic matrix composites from combustion atmospheres in advanced gas turbines. EBCs, as diffusion barriers for water vapor, are required to be dense, crack-free, uniform, and with well-matched thermal expansion compared to Si-based substrates.

In this study, the fabrication of ytterbium-disilicate-based environmental barrier coatings by using suspension plasma spray are reported. Characteristics of these EBCs are represented in terms of density and phase formation with different spraying and feedstock conditions. The possibility of these coatings as environmental barrier application is also investigated.