Effect of geometrical distribution of sub-grain boundaries on creep properties of Ni-based superalloys

几何要求的位错分布在亚晶界，对应于ni基高温合金中生长的枝晶界面。在本研究中，我们进行了压缩蠕变试验，以观察伽玛/伽玛素界面和平行筏结构的蠕变位错网络的发展。当沿生长方向施加压应力时，与垂直于生长方向施加的压应力相比，初级蠕变的幅度很小。我们制造了一台蠕变试验机，它可以使用一个非常小的没有位错网络的试样。

Geometrically required dislocations are distributed at sub-grain boundaries that corresponds to interfaces of dendrites grown in Ni-based superalloys. In the present study, we have performed compressive creep tests to observe the development of creep dislocation networks at gamma/gamma-prime interfaces, and of parallel raft structure. When a compressive stress is applied along tothe growth direction, the magnitude of primary creep is very small compared with that applied perpendicular to the growth direction. We have constructed a creep testing machine that can use a very small specimen without dislocation networks in it.