The spreading behavior of CMAS melt on YSZ single crystal with low index orientation

[Display omitted] •The real-time contact angles are measured to characterize the spreading behavior.•The empirical formula of CMAS spreading on single crystalline YSZ is established.•Microstructure caused by CMAS corrosion on YSZ is related to orientation.•Interface microstructure plays an important role in spreading process. The spreading behavior of CMAS melt on cubic crystalline YSZ with low index orientation is studied by observing the variation of contact angles of CMAS melt on YSZ surface and the microstructure change caused by thermal chemical corrosion. In this study, the empirical formula of CMAS spreading on YSZ is established based on the experimental results. Whether in the vacuum or in the air, the tendency of the equilibrium contact angle of molten CMAS on the surface of single crystalline cubic YSZ is 〈1 0 0〉 > 〈1 1 1〉 > 〈1 1 0〉, and the spreading speed increases as 〈1 0 0〉