【摘要】 通过试验的方法研究TC4合金在700℃～850℃和0.001～0.1 s^-1条件下的高温流变行为和微观组织演变规律，建立一套TC4钛合金高温统一黏塑性本构模型，分析该模型计算结果与实验数据的吻合程度。研究结果表明：随着温度升高、应变速率降低，材料流变应力降低，延伸率升高，并在850℃、0.001 s^-1时达到最大延伸率119%。升高温度、降低应变速率及增加应变量能促进材料发生动态再结晶，形成小尺寸等轴晶粒。统一黏塑性本构模型在700℃～800℃下预测值与实验值相关性高于0.9,可以很好地预测TC4钛合金的高温流变行为和流变应力。更多还原

【Abstract】 The high temperature flow behavior and microstructure evolution of TC4 alloy at 700 ℃-850 ℃ and 0.001-0.1 s^-1 was studied by experiment. A set of high temperature unified viscoplastic constitutive model for TC4 titanium alloy was established, whose coincidence degree of caculation results and experimental data was analyzed. The results show that with the increase of temperature, the strain rate decreases, the flow stress decreases and the elongation increases, and the maximum elongation reaches 119% at 0.001 s^-1 and 850 ℃. The temperature increasing, strain rate decreasing and strain increasing can promote the dynamic recrystallization and the formation of small equiaxed grains. The unified viscoplastic constitutive model, whose correlation between the predicted value and the experimental value is higher than 0.9 at 700 ℃-800 ℃, can well predict the high temperature flow behavior and flow stress of TC4 titanium alloy.更多还原