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对高度稳定化β型阻燃钛合金Ti40的氧化机理和氧化层剥落机理进行研究表明：合金氧化增重随温度升高明显增加，至1050℃反而降低；600℃的氧化膜主要为TiO2和V2O5，高于700℃氧化，因V2O5的挥发，氧化膜主要为TiO2，随温度升高，氧化物晶粒粗化，氧化膜疏松多孔，与基体黏附性降低，不低于900℃时开裂和剥落，不低于800℃氧化，氧化层疏松处还存在SiO化合物，温度升高，SiO数量增多，由圆球形变为星形，至1050℃随氧化层剥落而消失；剥落后的基体氧化层仍为疏松状，有不连续分布的Cr2O3膜存在。同时还分析了Ti40合金不抗氧化的原因及氧化机理，提出了氧化机理模型。在分析氧化膜内应力产生及内应力释放机制基础上，提出了Ti40合金氧化层开裂、剥落机理。

The alloy Ti40 is a highly stabilized β type burn resistanttitanium alloy. The oxidation and peel-off mechanisms of oxide layer of this alloy have been studied. The experimental results indicate that weight gain increases greatly with increasing temperature, however, the weight gain decreases for oxidizing at 1 050℃. The main products oxidized at 600℃ are TiO2 and V2O5. If oxidizing temperature is higher than 700℃, TiO2 is the main products because of the vaporization of V2O5. With increasing temp erature and time, the grains of oxide become coarse, the oxide film is porous, and the coherence force between oxide scale and matrix decreases. The oxide scale cracks and peels if temperature is not less than 900℃. There are SiO compound in porous oxide scale if temperature is not less than 800℃. The amount of SiO i ncreases with increasing temperature. The SiO compound changes from ball to star state, and vanishes after peel of oxide scale at 1 050℃. There are non-contin uous Cr2O3 product at the interface between oxide scale and matrix. The reas on is that the alloy Ti40 does not possess good oxidation resistance. The oxidat ion mechanism is also analyzed, and a oxidation model is proposed. The mechanisms of crack and peel of oxide scale are discussed in detail.