Additive manufacturing enables the fabrication of complex engineering components previously inaccessible through traditional processes. Nickel-base superalloys with large \(\gamma^{\prime}\) volume fraction are typically considered non-weldable and therefore exhibit a propensity for cracking during the fusion process. These crack-prone materials, however, are of great importance in gas turbine engines due to their excellent high temperature creep resistance. In this study we investigate the creep behavior of IN738LC produced by the electron beam melting process. We find that with appropriate post-build heat treatment the creep response of material oriented in the build direction exhibits deformation and rupture behavior comparable to that of conventionally cast IN738 & IN738LC. In the transverse direction properties fall below the expected cast behavior, however, we argue this is likely due to differences in grain scale and crystallographic texture. It may be possible to coarsen the grain morphology with appropriate process-parameter optimization in order to reduce the severity of intergranular fracture in the transverse direction. These results illustrate that high temperature properties exhibited by additively manufactured IN738LC are suitable for the hot section of gas turbine engines.

增材制造可以制造以前通过传统工艺无法获得的复杂工程部件。具有大\（\ gamma ^ {\ prime} \）的镍基高温合金体积分数通常被认为是不可焊接的，因此在熔融过程中表现出开裂的倾向。但是，由于这些易裂纹的材料具有出色的耐高温蠕变性能，因此在燃气涡轮发动机中非常重要。在这项研究中，我们研究了电子束熔化过程产生的IN738LC的蠕变行为。我们发现，通过适当的后置热处理，在构建方向上定向的材料的蠕变响应显示出与常规铸造IN738和IN738LC相当的变形和断裂行为。在横向方向上，性能低于预期的铸造性能，但是，我们认为这可能是由于晶粒尺寸和晶体学纹理的差异所致。可以通过适当的工艺参数优化来粗化晶粒形态，以降低横向晶粒间断裂的严重性。这些结果表明，由增材制造的IN738LC表现出的高温特性适用于燃气涡轮发动机的高温部分。