带温度梯度的钴基高温合金蠕变性能研究

Research on Creep Behavior of Cobalt-Based Superalloy under Temperature Gradient

二元隔热衬套是航空发动机高温燃气尾喷管的关键部件,在服役状态下承受非均温、蠕变等复杂环境与载荷。开展了二元隔热衬套钴基高温合金材料GH5188在温度梯度下的蠕变性能研究,设计了具有二元衬套孔结构特征的平板模拟件,开发了带温度梯度的蠕变加载试验装置,进行了内外壁温度差为200℃(760/560℃)以及760、980℃均温条件下带孔与不带孔二元隔热衬套模拟件的蠕变试验。研究表明:在均温与温度梯度环境下带孔模拟件蠕变寿命均高于无孔试样的,带孔试样的蠕变变形显著低于无孔试样的。

Two-dimensional insulation casing is the key component of high-temperature gas tail-pipe nozzle of aero-engine,which suffers from complex environment and loadings including non-uniform temperature,creep loading,and so on during the service period.The creep behavior of cobalt-based superalloy GH5188 for two-dimensional insulation casing was studied under temperature gradient environment.The flat plate simulated specimens with holes were designed,and a creep test device with temperature gradient was developed.The creep tests of flat plate specimens with holes and without holes were carried out at a temperature difference of 200℃(760/560℃)and constant temperature(760,980℃).The results show that the creep life of flat plate specimens with holes is always longer than that of the specimens without holes and the creep deformation of flat plate specimens with holes is significantly lower than that of specimens without holes under the uniform temperature and temperature gradient.