Oxidation Behavior of a Ti3Al–Nb Alloy with Surface Thin Oxide Films
Thin films of aluminum, cerium, and yttrium oxides were applied onto the surfaces of Ti3Al–11Nb samples using an electrodeposition technique. The oxidation behaviors of the Ti3Al–Nb alloy, with and without these surface-applied films, were studied in air at 800–1000°C. The results showed that the oxidation rate of the alloy can be reduced by Ce oxide and Y oxide films, and the greatest improvement comes from oxidation of the Y oxide-coated specimens at 800°C. With increasing oxidation temperature, the difference between the Co-oxide and Y-oxide films becomes smaller. The results also indicated that the Ce-oxide and Y-oxide films can significantly improve the oxide scale-spallation resistance. On the other hand, Al-oxide films result in detrimental effects on the oxidation and scale-spallation resistance of the Ti3Al–Nb alloy. Based on the experimental results, the effects of the different surface films on the oxidation mechanism are discussed.