针对涡轮盘用GH4169合金,在不同温度(550,650,750 ℃)下开展了应力松弛试验,并根据应力松弛曲线建立了蠕变本构方程.结果表明:GH4169合金在不同温度下的应力松弛曲线呈现出相同的特点,整个应力松弛过程可以分为快速松弛和缓慢松弛并趋于稳定两个区段;拟合曲线与试验曲线的符合程度表明二阶指数衰减函数可以很好地用来描述该合金的应力松弛过程;不同温度下应力-蠕变应变速率关系曲线可划分为低应力区、过渡区和高应力区三个区段,在低应力区与高应力区,应力与蠕变应变速率关系基本呈线性相关;通过Origin8.0软件对应力-蠕变应变速率关系曲线进行拟合得到了不同温度下的材料常数,建立了该合金的蠕变本构方程.

Stress relaxation tests were carried out at various high temperatures (550,650 ℃ and 750 ℃) on GH4169 superalloy used for turbine disk,and the creep constitutive equations were built according to stress relaxation curves.The results show that the stress relaxation curves of GH4169 superalloy presented the same characteristics at different temperature,the stress relaxation process could be divided into the stage of fast relaxation and the stage of stabilization.Second order exponential decay function could be well used to describe the stress relaxation process of GH4169 superalloy.Throughout the entire stress relaxation process,the stress and creep strain rate curves could be divided into three stages,low stress stage,transition stage and high stress stage.The relationship of stress and creep strain rate in the low stress stage and the high stress stage both presented linear correlation.By fitting the stress and creep strain rate curves using software Origin 8.0,the material constants in creep constitutive equations of GH4169 superalloy were obtained.