We review briefly the literature on coarsening in elastically stressed solids and present the results from a large scale simulation of Ostwald ripening of second-phase particles ion an elastically anisotropic system. We perform the simulation in two dimensions, and achieve the necessary computational accuracy and efficiency by adopting the boundary integral method and the fast multipole method. Both the particles and the matrix are assumed to posses the same elastic constants but are anisotropic with cubic symmetry. The interfaces are assumed to be coherent. A large scale simulation starts with 4000 circular particles placed randomly in the computational domain. We calculate the evolution of the system and follow the change in particle shapes, the relative particle positions, and the average particle size. In this paper, we will present the results on the microstructure evolution, focusing our attention on low-volume-fraction systems in which the interfacial energy is dominant at the initial stage of the simulation. It is found that the morphology that develops during coarsening is significantly different when elastic stress is present. The qualitative nature of the changes is presented both in physical space and in the scattering functions. The development of particle shapes is examined by studying the shape factor, a measure of deviation of a shape from a circular shape. The result shows that the average shape factor does not follow the same evolution path as given by the shape factor of an isolated particle in equilibrium with the same ratio of elastic and interfacial energy after elastic energy becomes dominant. In addition, the weighted radial distribution functions show the development of the spatial correlations during coarsening. We find that the radial distribution functions are not isotropic and can be uniquely determined when the ratio of elastic and interfacial energy is given.
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