The microscopic diffusion equation combined with the theory of microscopic elasticity was used. The elastic straininduced morphological transformation of a binary model alloy containing 25% (percentage of solute atoms) was simulated. The results show: when the elastic strain energy was neglected

randomly distributed equiaxed particles were obtained with isotropic characteristic; when the elastic strain was considered

precipitates tend to aligned along the elastic \!soft\" directions with anisotropic characteristic. The selectively growth and coarsen of precipitates occur along the optimum directions.