中文摘要：

在Gleeble 3800热模拟试验机上进行GH4706合金的热压缩实验,研究了变形温度为900～1150℃、应变速率为0.001～1s^-1范围内合金的热变形行为。结果表明：GH4706合金的真应力-真应变曲线呈现出流变软化特征,随变形温度增加或应变速率减小,峰值应力逐渐降低,峰值应变逐渐减小。合金的本构关系可由双曲正弦函数描述,变形激活能为435.36kJ/mol,应力指数为4.13。合金的显微组织演化机制与Z参数密切相关,高Z值条件下主要发生动态回复,低Z值条件下主要发生动态再结晶与再结晶晶粒粗化。GH4706合金发生完全动态再结晶且不发生晶粒粗化的临界lnZ值为35。

英文摘要：

The hot deformation behavior of GH4706 alloy was investigated by compressive deformation performed on Gleeble 3800 machine at deformation temperature of 900-1150℃ and at strain rates of0.001-1s^-1.The results show that the true stress-true strain curves exhibit flow softening characteristic,the peak stress and peak strain decrease gradually with the increase of deformation temperatures or decrease of strain rates.Further,the constitution relationship is modeled using the hyperbolic-sine Arrhenius-type equation.The activation energy and stress exponent are 435.36kJ/mol and 4.13,respectively.The mechanisms of microstructure evolution are related to Zparameter,the domain mechanism is dynamic recovery at higher Z;while is dynamic recrystallization and grain coarsening at lower Z.The critical value of lnZ which the microstructure is completely dynamic recrystallization without grain coarsening is 35.