(中南大学航空航天学院，长沙 410083)
摘 要: 采用热模拟试验机研究δ相时效态GH4169合金在变形温度为980~1100 ℃、应变速率为1×10-3~1s-1条件下的热压缩变形行为，绘制真应力-真应变曲线。结果表明：该合金在变形过程中出现了明显的动态软化行为。利用摩擦修正后的峰值应力数据构建了该合金的热压缩本构方程，获得了本构方程材料常数分别为α=0.005626、n=4.2643、A=5.6185×1017、Q=486.8 kJ/mol。构建了不同应变量ε下合金本构方程材料常数的五次多项式组，并根据多项式对其流变应力进行了预测。结果表明其预测数据与摩擦修正数据基本相符。利用动态材料模型方法建立了该合金在不同应变量下的热加工图，分析了其在不同变形条件下的动态再结晶特性及流变失稳行为。
关键字: GH4169合金；本构方程；热加工图；动态再结晶；流变失稳
（School of Aeronautics and Astronautics, Central South University, Changsha 410083, China）
Abstract:The hot compressive deformation behavior of delta-processed GH4169 alloy was investigated at temperature range of 980-1100 ℃ with strain rate from 1×10-3 to 1 s-1by thermal simulator. The true stress-true strain curves were obtained. The results show that the apparent dynamic softening behaviors occur during deformation. By using the friction-corrected peak stress data, the constitutive equation of the alloy for hot compression was established. The material constants are obtained to beα=0.005626, n=4.2643, A=5.6185×1017, Q=486.8 kJ/mol, respectively. A group of five-order polynomials showing the relationship between material constants of the constitutive equation and the strain was constructed, by which the flow stress was predicted. The predicted data are in good agreement with the friction-corrected one.According to the methods of dynamic material model, the hot processing maps of the alloy at different strains were established. The dynamic recrystallized characteristic under different deformation conditions and the flow instability behavior were also analyzed.
Key words: GH4169 alloy; constitutive equation; hot processing map; dynamic recrystallization; flow instability
