Sol–gel-based coatings for oxidation protection of TiAl alloys.

The low density, high specific strength, and good creep properties make TiAl alloys being promising high-temperature structural materials in aerospace and automotive industries. However, the insufficient oxidation resistance limits their extensive practical applications. It is the intention of this review to illustrate the mechanism and development of sol–gel-based coatings, a surface modification approach for oxidation protection of TiAl alloys, but not to present a general review on the oxidation protection of TiAl alloys. The oxidation behavior and mechanism of TiAl alloys were addressed briefly. The discussion focused mainly on the sol–gel coatings preparation method and generation mechanism. Finally, the development trend of sol–gel-based coatings for high-temperature oxidation of TiAl alloys was prospected. [ABSTRACT FROM AUTHOR]