Tensile interruption experiments with different strains were conducted on additively fabricated nickel-based Inconel 939 superalloys at 700 ℃ to investigate the evolution of multiple deformation mechanisms. The microstructures of different strain groups captured by transmission electron microscopy (TEM) were analyzed, and it was concluded that a total of four various deformation mechanisms were identified, of which the first to be activated was the Orowan loop bypassing γ', and a tendency of transition from double to single loop was observed. Anti-phase boundary (APB) shearing was subsequently initiated, with a needed critical resolved shear stress level of approximately 195.82 MPa. Stacking faults (SFs) and deformation twinnings (DTs) were observed at higher stress, accompanied by the dissociation of dislocations. In addition, the magnitude of the stacking fault energy of AM 939 superalloys at intermediate temperature was calculated and estimated by matching the experimental phenomena with the critical shear stress.

中文翻译：

---

γ'-Ni3(Al, Ti)强化增材制造镍基939高温合金中温塑性变形的演化机制

在700 ℃下对增材制造的镍基Inconel 939高温合金进行了不同应变的拉伸中断实验，以研究多种变形机制的演变。对透射电子显微镜（TEM）捕获的不同应变组的微观结构进行了分析，得出的结论是，总共识别出四种不同的变形机制，其中首先被激活的是绕过γ'的Orowan环，并且有一种趋势观察到从双环到单环的转变。随后启动反相边界 (APB) 剪切，所需的临界解析剪切应力水平约为 195.82 MPa。在较高应力下观察到堆垛层错（SF）和变形孪晶（DT），并伴有位错解离。此外，通过将实验现象与临界剪切应力相匹配，计算和估计了AM 939高温合金在中温时的堆垛层错能的大小。