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研究了Ａｌ含量为３３．３ａｔ％～５２ａｔ％Ａｌ的５种二元Ｔｉ－Ａｌ合金在８００℃和９００℃空气中的恒温氧化行为，用Ｘ射线衍射仪和扫描电子显微镜对其氧化产物、氧化物表面形貌和氧化层剖面结构进行了分析。研究发现：在该Ａｌ含量范围内，二元Ｔｉ－Ａｌ合金的氧化层均由具有典型形貌特征的一系列氧化薄层组成，而且在氧化层中均未形成连续致密分布的Ａｌ２Ｏ３；Ａｌ含量对氧化层中Ａｌ２Ｏ３的形态、分布以及恒温氧化反应速率影响较大；８００℃恒温氧化时，随Ａｌ含量的增加其抗氧化能力提高，９００℃时，除５２ａｔ％Ａｌ以外，其它几种合金仍符合这个规律，但５２ａｔ％Ａｌ恒温氧化１００ｈ的增重要高于４６ａｔ％、４８ａｔ％、和５０ａｔ％Ａｌ。同时对Ａｌ含量影响二元Ｔｉ－Ａｌ合金高温氧化行为的机理也进行了探讨。
Five kinds of binary Ti-Al alloys with 33.3at% ~ 52at% Al were investigated for their isothermal oxidation behavior in air at 800 ℃ and 900 ℃. Their oxidation products were characterized by X-ray diffraction (XRD) and scanning electron microscopy Surface morphology and oxide layer profile structure were analyzed. The results show that in the range of Al content, the oxide layer of binary Ti-Al alloy is composed of a series of thin oxide layers with typical morphologies, and no continuous dense Al2O3 is formed in the oxide layer. Al content The results show that the oxidation resistance increases with the increase of Al content at 800 ℃. In addition to 52at% Al at 900 ℃, According to this rule, the thermostatic oxidation of 52at% Al for 100h has higher weight gain than 46at%, 48at%, and 50at% Al. At the same time, the mechanism of Al content influencing the high temperature oxidation behavior of binary Ti-Al alloy was also discussed.