中文摘要：

采用相场模型对外加应力场对共格沉淀析出过程的微观结构演化进行模拟研究，在外加应力场作用下，非均匀弹性模量系统沉淀相的析出过程发生重大的变化，粒子沿弹性软方向呈各向异性析出，这种各向异性生长与外加应力、点阵错配度的符号以及非均匀模量差的符号有关。采用双级时效模拟方式时，外加应力场对析出相的成核及生长阶段均有影响，只是影响程度与析出相自身的点阵错配度有关。对适当的体系采用应力时效的方式可能是实现除分子束外延技术之外的一种全新的制备超晶格微结构的方法。

英文摘要：

The effect of external stress on the microstructure evolution of alloys containing coherent precipitates was studied by phase field model. In an elastically inhomogeneous system, an applied strain can result in the selective growth of precipitates with homogeneous strain field, which depends on the signs of the applied strain, lattice misfit and the elastic inhomogeneity. Both nucleation and growth are affected by the external stress by two-step aging simulation, but the effect degree depends on lattice misfit. The stress aging technology can be used to obtain superlattice structure for some special systems.