【摘要】 本研究在Gleeble-1500热模拟试验机上对镍基耐蚀合金G-3进行了热压缩试验,研究了合金变形温度在900～1250℃之间,应变速率为1～0.01s^-1条件下的热变形行为。在热模拟试验数据的基础上,通过多元线性回归及动态材料模型建立了合金热变形本构方程及热加工图,利用其系统地研究了合金的热变形工艺参数。结果表明:G-3合金在热变形时呈现出不同的动态再结晶峰区,峰区Ⅰ和峰区Ⅲ动态再结晶不完全,变形后形成了不均匀的混晶组织,不利于合金的热加工;而峰区Ⅱ为完全动态再结晶区,变形后晶粒均匀,是热变形的理想区域。该区对应的变形温度/应变速率范围为1150～1210℃/0.01～0.08s^-1,功率耗散因子峰值为44%。变形温度低于1050℃和变形速率高于0.1s^-1时,合金的功率耗散因子降低,属于变形危险区,G-3合金的热加工应该避免在该区进行。更多还原

【Abstract】 Hot deformation behavior of G-3 alloy in the temperature range of 900-1250 ℃ and strain rate range of 1-0.01 s^-1 was studied by hot compressing test using a Gleeble-1500 simulator.The constitutive equation and processing map were derived with multiple linear regression and the dynamic material model to study the hot deformation parameters.The results show that G-3 alloy has different dynamic recrystallization peak zones during deformation processes:Zones I and III are incomplete recrystallization regions,in which the hot deformation is not easy to be conducted.Zone II is the complete dynamic recrystallization region which is propitious to hot deformation.The optimized processing parameters are within the temperature range of 1150℃ to 1210℃ while the strain rate is from 0.01 s^-1 to 0.08 s^-1,with the peak power dissipation of 44%.The power dissipation factor decreases when the deformation temperature is lower than 1050℃ and the strain rate higher than 0.1 s^-1,in which region microcracks form and thermal processing is not suitable to be conducted.更多还原