Al-modified environmental barrier coatings for protection against water vapor corrosion

High-temperature water vapor corrosion is a great challenge for long lifetime of Si/mullite/Yb2SiO5 Environ-mental Barrier Coatings. In this work, the Yb3Al5O12 modified layer was in-situ synthesized on the surface of Yb2SiO5 layer to improve the steam resistance. The reaction mechanism of the Al-modified layer was explored. The steam corrosion experimental results indicated that the defects in Yb2SiO5 layer healed, and the oxidation rate of Si-bonded coating was slowed down under the protection of modified layer. Additionally, the calculation results of first-principle molecular dynamics confirmed that Yb3Al5O12 has excellent steam corrosion resistance.

Automated summary

In this study, a Yb3Al5O12 modified layer was synthesized on the surface of Yb2SiO5 to improve the steam resistance of Si/mullite/Yb2SiO5 Environmental Barrier Coatings. The reaction mechanism of the Al-modified layer was explored and experimental results showed that the modified layer healed defects in the Yb2SiO5 layer, leading to a slower oxidation rate of the Si-bonded coating. Additionally, first-principle molecular dynamics calculations confirmed the excellent steam corrosion resistance of Yb3Al5O12.