OXIDATION MECHANISM OF BINARY Ti-Al ALLOYS AT ELEVATED TEMPERATURE
二元Ti—Al合金高温氧化机理

The isothermal oxidation behavior of Ti-33.3% Al, Ti-48% Al and Ti-52%Al(atomic fraction) intermetallic compounds oxidated at 1073 and 1173K in air was investigated. The reaction products of the oxidation scale were examined by XRD, and the surface morphology and cross-section microstructure of the oxidation scale were analyzed by SEM equipped with EDS. The results indicated that the oxidation scale of binary Ti-Al alloys was consisted of a series of thin layers, and the oxidation process could be classified into three steps, the growing direction of the oxidation scale and the rate-controlling factor of various steps is somewhat different; the isothermal oxidation kinetic curves mainly follow parabolic rate law.