Preparation and high temperature oxidation behaviors of (Al-Y)-dipped TiO2/Al2O3 composite coatings on the surface of Fe-Al alloy

Sol-gel method combined with dipping process was used to prepare (Al-Y)-dipped TiO2/Al2O3 composite coatings on the surface of Fe-Al alloys. Oxidation thermodynamic results show the composite coatings caused lower oxidation weight gain than the sample without this coating. Combination of XRD and SEM results illustrates that the cross section morphology composed of an outermost layer of loosen Al and then a thick layer of Fe2O3, and a continuous Al2O3 innermost layer. This work shows that through appropriate designing of the composite coatings, better high temperature oxidation resistance alloy which can be prepared rapidly and simply can be obtained.