Oxidation behaviors and mechanisms of Yb2SiO5-Yb2O3-Si-SiC ceramic fabricated by tape casting and reactive melt infiltration

The phase transition of thermally grown oxide (TGO) has been proven to be an important factor affecting the durability of EBCs. Yb 2 O 3 and Yb 2 SiO 5 can react with silica to form silicate, which can reduce the TGO thickness and extend the lifetime of EBCs. In this paper, the Yb 2 SiO 5 -Yb 2 O 3 -Si-SiC ceramic was prepared by tape casting combined with silicon reactive melt infiltration. The oxidation properties of the ceramic were evaluated at 1200–1400 °C. With the increase in temperature, the content of SiO 2 in the oxide layer decreased and the content of Yb 2 Si 2 O 7 increased. A dense and continuous Yb 2 Si 2 O 7 layer was formed at 1400 °C. Yb 2 Si 2 O 7 is formed at the edge of Yb 2 SiO 5 , then Yb 3+ diffuses outwards, Si 4+ diffuses inwards and gradually forms Yb 2 Si 2 O 7 from the outside to the inside.