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Ｔｉ－４０合金是全β型阻燃钛合金。利用Ｇｌｅｅｂｌｅ－１５００热模拟试验机研究该合金铸态的高温（８５０～１１００℃）变形机制和应力－应变（σ－ε）关系。结果表明，Ｔｉ－４０合金σ－ε曲线上，流变应力有一突降随后稳定的现象；恒定温度，应变速率升高，应力升高，流变应力降低幅度增大；恒定应变速率，温度升高，应力降低，流变应力降低幅度减小；铸态Ｔｉ－４０合金高温变形的应力指数ｎ为４．３５，变形激活能Ｑ为２２５ｋＪ／ｍｏｌ，说明该合金的高温变形机制为扩散控制的过程。Ｔｉ－４０合金高温变形的本构方程为：ε＝ｅ９．９８３σ４．３５ｅｘｐ（－２５５０００／ＲＴ）；将σ＝Ｋεｍ关系式中的Ｋ作为随试验条件变化的参数，求得的峰值应力比的理论值与试验值相近。
Ti-40 alloy is all β-type flame-retardant titanium alloy. The relationship between the deformation mechanism and the stress-strain (σ-ε) of as-cast as-cast high temperature (850 ~ 1100 ℃) was studied by using Gleeble-1500 thermal simulation machine. The results show that on the σ-ε curve of Ti-40 alloy, the flow stress has a sudden drop and then stabilizes. The constant temperature, the strain rate increases, the stress increases and the flow stress decreases. The constant strain rate, temperature rise High, the stress decreases and the reduction of the flow stress decreases. The stress exponent n of the as-cast Ti-40 alloy is 4.35 and the activation energy Q is 225kJ / mol, which indicates that the high-temperature deformation mechanism of the alloy is diffusion-controlled process. The constitutive equation of high-temperature deformation of Ti-40 alloy is: ε = e9.983σ4.35exp (-255000 / RT); K in the relationship of σ = Kεm is taken as a parameter that changes with experimental conditions, and the peak stress ratio The theoretical value and test value are similar.