The creep behaviors of Ni3Al-based single crystal alloy IC6SX with [001] and [111] orientations under the condition of 850°C/450 MPa were investigated. The effect of crystal orientation on the creep lives, fracture morphology, fracture mechanism, and dislocation evolution of the alloys with different orientations was analyzed systematically. The results showed that the creep lives of the alloy were closely related to the crystal orientation under the condition of 850°C/450 MPa. The creep lives of the single crystal alloys with [001] and [111] orientations were 56.3 h and 126.9 h, respectively. Moreover, the fracture morphologies of the two alloys with [001] and [111] orientations were different. The results showed that some holes formed at the fracture surface of the alloy with [111] rather than [001] orientation. Furthermore, the surface near the fracture of the two alloys with [001] and [111] orientations was serrated. Therefore, the fracture mechanism of the single crystal alloys with [001] and [111] orientations was ductile fracture. In addition, a large number of dislocations cut into the phase. Therefore, the cutting mechanism of dislocations in the alloys with [001] and [111] orientations was the creep deformation mechanism.

中文翻译：

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Ni3Al基单晶合金850℃/450 MPa蠕变行为研究

研究了[001]和[111]取向的Ni3Al基单晶合金IC6SX在850℃/450 MPa条件下的蠕变行为。系统地分析了晶体取向对不同取向合金蠕变寿命、断裂形貌、断裂机制和位错演化的影响。结果表明，合金在850℃/450 MPa条件下的蠕变寿命与晶体取向密切相关。[001]和[111]取向的单晶合金的蠕变寿命分别为56.3小时和126.9小时。此外，[001]和[111]取向的两种合金的断裂形貌不同。结果表明，在合金断口处形成了一些孔洞，其取向为[111]而不是[001]。此外，具有[001]和[111]取向的两种合金断裂附近的表面是锯齿状的。因此，具有[001]和[111]取向的单晶合金的断裂机制是韧性断裂。此外，大量位错切入相中。因此，[001]和[111]取向合金中位错的切割机制是蠕变变形机制。