Interaction of multicomponent disilicate (Yb0.2Y0.2Lu0.2Sc0.2Gd0.2)2Si2O7 with molten calcia-magnesia-aluminosilicate

Abstract

Environmental barrier coating (EBC) materials that are resistant against molten calcia-magnesia-aluminosilicate (CMAS) corrosion are urgently required. Herein, multicomponent rare-earth (RE) disilicate ((Yb0.2Y0.2Lu0.2Sc0.2Gd0.2)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.].