中文摘要：

采用Thermecmastor-Z型热模拟试验机对铸态TB6钛合金在真应变为0.92、变形温度为950~1100℃、应变速率为0.001~10 s-1的条件下进行等温恒应变速率压缩试验,研究了该合金在β单相区的热变形行为及变形机制。结果表明,该合金的流动应力曲线主要呈流动震荡和流动软化两种特征。在0.001~0.01 s-1时,流动曲线呈小幅度流动震荡;而在10 s-1时,流动曲线呈大幅度流动震荡;在0.1~1 s-1时,流动曲线呈流动软化特征。通过微观组织观察可知：当应变速率为0.001 s-1时的变形机制为动态再结晶;在0.01~1 s-1时的变形机制主要为动态回复;在10 s-1时的变形机制为局部流动。从细化组织和降低变形抗力方面考虑,应变速率以不超过0.1 s-1为宜。

英文摘要：

Isothermal constant strain rate compression tests on the as-casted TB6 titanium alloy at temperature of 950-1100 ℃ and strain rate of 0.001-10 s-1 were conducted up to a true strain of 0.92 using the Thermecmastor-Z hot temperature simulator.The hot deformation behavior and deformation mechanisms were studied in the β phase field.The results show that characteristics of flow stress curves of this alloy mainly are of flow oscillation feature and flow softening behavior.The flow stress curve is of the small flow oscillation at 0.001~0.01 s-1,but the wide range of flow oscillation at 10s-1 and the flow stress curves show flow softening behavior at 0.1~1s-1.Microstructure observation indicates that the deformation mechanism of this alloy exhibits dynamic recrystallization feature at 0.001s-1,which shows dynamic recovery behavior as the main deformation mechanism at 0.01~1s-1 and flow localization behavior at 10s-1,respectively.According to the effect of grain refinement and reduction of resistance of deformation,the appropriate strain rate should be no more than 0.1s-1.