Enhanced high temperature oxidation resistance for γ-TiAl alloy with electrodeposited SiO2 film

Thickness controllable SiO 2 film was prepared on γ-TiAl alloy by cathodic electrodeposition . The oxidation behaviour of the specimens at 900 °C was studied. The effects of SiO 2 electrodeposition parameters, such as electrolysis time and deposition current density, on the morphology, structure and high temperature oxidation performance of the film were investigated. Results shown during thermal oxidation, the electrodeposited SiO 2 film could react with the TiAl alloy to form an alumina- and silicon-enriched glass-like oxide scale, which can prevent the inward diffusion of oxygen from air to the film/alloy interface, resulting in the remarkable decreased oxidation rate of the alloy.