【摘要】 利用平面应变压缩实验,研究TC21G钛合金在变形温度为870～940℃、应变速率为0.1～1 s^-1条件下的变形行为,并分析显微组织的演变过程。同时,研究加工参数对应变硬化指数n值的影响。结果表明:在应变速率一定的条件下,随着变形温度的升高,显微组织中β相的含量增加,合金的流变应力降低;而在变形温度一定的条件下,随着应变速率的增加,可动位错的迁移速率增加,从而使合金的流变应力升高。TC21G钛合金在两相区进行变形,随着变形温度的升高,应变量的增加以及应变速率的降低,片层α相的球化程度增加。基于显微组织的分析可知,应变硬化指数n值与绝热升温效应,β相的动态再结晶（DRX）以及动态回复（DRV）有密切的关系。更多还原

【Abstract】 The hot deformation behavior in plane strain compression of the TC21G titanium alloy was investigated in the deformation temperatures ranging from 870 ℃ to 940 ℃, the strain rates ranging from 0.1 s^-1 to 1 s^-1. The microstructures evolution was also analyzed. Meanwhile, the effect of processing parameters on the strain hardening exponent n was analyzed. The results show that, under the condition of a certain strain rate, the flow stress of alloy decreases with the increase of the deformation temperature due to the increase of β phase content. However, in the condition of a certain temperature, the flow stress of alloy increases with the increase of the strain rate, because the velocity of mobile dislocations increases. During deforming in the α+β field, with the increase of the deformation temperature or strain, and the decrease of the strain rate, the globularization degree of the lamellar α phase increases. Based on the microstructure examination, the variation of n values is found to depend on the adiabatic heating effect, dynamic recrystallization（DRX） and dynamic recovery（DRV） of β phase.更多还原