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为研究Ru对高代单晶高温合金组织稳定性的影响,制备分别含有6％和4.5％Ru(质量分数)的2种单晶高温合金D1和D2,完全热处理后置于980和1160 ℃下进行200 h的长期时效,分析合金长期时效后的显微组织、不稳定拓扑密排相(TCP)成分及晶体结构.结果表明:980 ℃时效200h后,含Ru较多的D1合金中TCP析出量显著多于D2合金;1160 ℃时效200h后,D1合金中未观察到TCP相,而D2合金中观察到少量TCP相;2种合金析出的TCP相为同一种TCP相,Ru为其主要形成元素之一.结合d电子能级计算和热力学计算分析表明:Ru对单晶高温合金TCP析出的影响具有两面性.一方面Ru含量提高会使合金d电子能级增大,增加合金TCP析出倾向;另一方面Ru含量增加可降低高熔点元素在γ相中的偏析程度,进而减小因高熔点元素在γ相中过饱和而导致的TCP相析出量;在不同温度下,起主要作用的因素会有所不同.“,”In order to study the effect of Ru on the microstructure stability of high generation single-crystal superalloys,two single-crystal superalloys D1 and D2 containing 6wt％Ru and 4.5wt％Ru were prepared,respectively.After complete heat treatment,they were long-term aged at 980 and 1160 ℃ for 200 h.The alloy microstructure of different scales,compositions of topologically close-packed(TCP)phase and TCP crystal structures were investigated.Results show that after long-term aging at 980 ℃ for 200 h,the precipitation of TCP in D1 alloy containing more Ru is higher than that in D2 alloy;after long-term aging at 1160 ℃ for 200 h,no TCP phase is observed in D1 alloy,while a small amount of TCP phase is observed in D2 alloy;the TCP phases in both alloys are of the same type,and Ru is one of the main forming elements.The experimental results were analyzed combined with d-electrons concept and thermodynamic calculation.Results show that the influence of Ru on the TCP precipitation of single crystal superalloys has two sides.On the one hand,adding Ru can increase the d-electron energy level of single crystal superalloys,which can increase the TCP precipitation tendency.On the other hand,the increase of Ru content can reduce the segregation of refractory elements in y phase,thus reducing the amount of TCP phase precipitation caused by the supersaturation of refractory elements.At different temperatures,the main influencing factors are different.