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为研究γ＇相定向粗化现象，采用有限元方法（ＦＥＭ）计算了单晶 Ｎｉ基γ和γ＇双相合金有／无外加载荷时的热错配应力及应变能密度．结果表明：外加载荷改变了γ和γ＇相内的ｖｏｎ Ｍｉｓｅｓ应力及应变能密度分布，与弹性应变相联系的共格应变能变化是γ＇相定向粗化的驱动力．外加拉伸或压缩应力，引起立方γ＇相不同界面晶格发生挤压或扩张应变，晶格的挤压应变可排斥γ＇相中原子半径较大的ＡＩ，Ｔａ等溶质元素；扩张的晶格可诱捕这些元素，以促进γ＇相的定向生长，因此，沿（１００）方向扩张晶格的法线方向是γ＇相形筏的生长方向．随γ＇相弹性扩张晶格应变及γ相粘滞塑性流变的增加，元素扩散及γ＇相形筏速率提高。
In order to study the coarsening of γ ’phase, the thermal mismatch stress and strain energy density of the single crystal Ni-based γ and γ’ dual-phase alloys with / without external load were calculated by the finite element method (FEM). The results show that the applied load changes the von Mises stress and strain energy density distribution in the γ and γ ’phases, and the coherent strain energy change associated with the elastic strain is the driving force for γ’ phase coarsening. In addition, tensile stress or compressive stress causes the lattice of the cubic γ ’phase to extrude or expand at different interfaces. The compressive strain in the lattice can exclude the solute elements such as Al and Ta with larger atomic radius in the γ’ phase. The lattice can trap these elements to promote the directional growth of the γ ’phase. Therefore, the normal direction of the lattice expanding along the (100) direction is the growth direction of the γ’ phase raft. With the increase of γ ’phase elastic expansion lattice strain and γ phase viscous plastic rheology, element diffusion and γ’ phase raft rate increase.