Samples cut from a 700 ℃/322 MPa/9117 h creep-ruptured specimen as well as a non-tested sample were characterized by electron backscatter diffraction to investigate the evolution of low ∑ (∑≤29) coincident site lattice boundaries during strain at elevated temperature for Haynes 282 superalloy. Results show that the proportion of ∑3 boundaries, including ∑9 and ∑27 boundaries, decreases sharply with increasing strain. The two-mode phase-field crystal method is applied to simulate the dynamic evolution process of a ∑3 boundary. During deformation at $\acute{\epsilon }=5.62e-6$, a twin embryo grows toward the initial ∑3 boundary with increasing strain and impinges onto it finally to form a ∑3-∑3-∑9 triple junction. In addition, part of the initial ∑3 boundary transforms into random grain boundary when the strain is large enough. Large numbers of dislocations are detected nearby ∑3 boundaries. They cause severe lattice rotations near ∑3 boundaries. In addition, some straight random boundaries can be found in strain zones only. Therefore, the transformation of ∑3 boundaries into random grain boundaries is the critical reason for the sharp decrease of ∑3 boundaries in strain zones.

通过电子反向散射衍射对从700℃/ 322 MPa / 9117 h蠕变断裂的样品以及未经测试的样品上切下的样品进行表征，以研究高应变时低∑（∑≤29）重合位点晶格边界的演化。 Haynes 282高温合金的最高温度。结果表明，随着应变的增加，Σ3边界的比例（包括Σ9和Σ27边界）急剧减小。应用双模相场晶体方法模拟了∑3边界的动态演化过程。在变形期间$\acute{\epsilon }=5.62Ë--6$，双胞胎胚胎随着应变的增加而朝着最初的Σ3边界生长，并撞击到其上，最终形成一个∑3-∑3-∑9三重连接。另外，当应变足够大时，初始∑3边界的一部分转换为随机晶界。在∑3边界附近检测到大量位错。它们会导致Σ3边界附近的严重晶格旋转。另外，仅在应变区域中可以找到一些直线随机边界。因此，将∑3边界转变为随机晶界是导致应变区∑3边界急剧减小的关键原因。