A self-healing environmental barrier coating: TiSi2-doped Y2Si2O7/barium strontium aluminosilicate coating

The TiSi2-doped Y2Si2O7/barium strontium aluminosilicate (BSAS) coating was fabricated on C/SiCs and corroded in a 50%H20-50%02 environment at 1250 C. The C/SiCs coated with TiSi2-doped Y2Si2O7/BSAS showed better durability than that coated with Y2Si2O7/BSAS. Microstructural studies showed that the through-thickness cracks in the TiSi2-doped Y2Si2O7/BSAS coating were filled with the oxidation products of TiSi2, indicating that the TiSi2-doped Y2Si2O7/BSAS coating has self-healing properties. Furthermore, the Y2Si2O7/BSAS coating doped with 15 wt% TiSi2 showed better durability than those doped with 10 wt and 20 wt TiSi2, indicating that 15 wt% TiSi2 is the optimum doping amount for Y2Si2O7/BSAS coatings. (C) 2016 Published by Elsevier B.V.