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研究了GH4049镍基高温合金在700℃．±0．45％应变控制条件下的疲劳－蠕变行为，发现合金在循环初始阶段是硬化趋势，随后呈软化趋势，利用透射电镜观察了合金在疲劳－蠕变不同阶段的形变结构，利用会聚束电子衍射技术研究了合金γ／γ’相错配度在疲劳－蠕变中的变化规律，结果表明．γ／γ’相的共格性在形变过程中未受到损失，均匀形变区内，基体位错密度迅速增加，导致合金循环形变初始硬化随形变进行，形变带内γ’相也发生形变，γ’相对基体位错运动阻碍作用降低，形成易滑移通道，合金逐渐软化
GH4049 nickel-based superalloy was studied at 700 ℃. The fatigue-creep behavior under ± 0.45% strain control found that the alloy is in the initial stage of the cycle is the hardening trend, followed by softening trend, the deformation structure of the alloy at different stages of fatigue - creep was observed by transmission electron microscopy, the use of convergence The results show that the γ / γ ’phase mismatch degree in fatigue - creep is studied by means of beam electron diffraction. The homogeneity of γ / γ phase is not lost in the deformation process. In the uniform deformation zone, the dislocation density of the matrix rapidly increases, causing the initial hardening of the cyclic deformation of the alloy to follow the deformation and deformation of the γ ’phase in the deformation zone. γ ’The relative movement of matrix dislocation obstacles to reduce the formation of easy slip-channel, the alloy gradually softened