A micromechanical model for predicting the directional coarsening behavior in Ni-based superalloys

A new micromechanical model based on the equivalent inclusion method has been developed to study the directional coarsening behavior in Ni-based superalloy single crystals. The von Mises stress, elastic strain energy density and hydrostatic pressure in different matrix channels are calculated when the external stress is applied along the [0 0 1], [1 1 0] and [1 1 1] directions, respectively. The calculated results are used to predict the directional coarsening behavior and raft morphology. The effects of the misfit and the external stress on the rafting behavior are carefully discussed.