Interaction of multicomponent disilicate (Yb_0.2Y_0.2Lu_0.2Sc_0.2Gd_0.2)₂Si₂O₇ with molten calcia-magnesia-aluminosilicate

Environmental barrier coating (EBC) materials that are resistant against molten calcia-magnesia-aluminosilicate (CMAS) corrosion are urgently required. Herein, multicomponent rare-earth (RE) disilicate ((Yb_0.2Y_0.2Lu_0.2Sc_0.2Gd_0.2)₂Si₂O₇, (5RE)₂Si₂O₇) was investigated with regard to its CMAS interaction behavior at 1400 °C. Compared with the individual RE disilicates, the (5RE)₂Si₂O₇ material exhibited improved resistance against CMAS attack. The dominant process involved in the interaction of (5RE)₂Si₂O₇ with CMAS was reaction-recrystallization. A dense and continuous reaction layer protected the substrate from rapid corrosion at high temperatures. The results demonstrated that multicomponent strategy of RE species in disilicate can provide a new perspective in the development of promising EBC materials with improved corrosion resistance. [Figure not available: see fulltext.].