Al2O3–ZrO2–Pt composite coatings prepared by cathode plasma electrolytic deposition on the TiAl alloy

• Al2O3–ZrO2–Pt composite coatings were prepared.
• Such coatings improve the cyclic oxidation resistance of TiAl alloy effectively.
• As PEG is added the current density is reduced significantly during CPED process.

Al2O3–ZrO2–Pt composite coatings were prepared by cathode plasma electrolytic deposition (CPED) on the TiAl alloy. Such coatings can improve the cyclic oxidation resistance of the TiAl alloy effectively. The beneficial results can be attributed to the effects: such coatings can inhibit further oxidation of alloy substrate owing to its extremely low oxygen diffusion rate, possess excellent mechanical properties owing to the stress relaxation caused by the phase transformation of zirconia, and the toughening role of Pt particles. In addition, as polyethylene glycol (PEG) is added in solution during CPED process, the current density is reduced significantly, and CPED would be a promising technique to deposit the uniform coatings on large-sized samples.