Abstract:The distribution of the von Mises stress and strain energy density in the regions near the interfaces of g/g ¢ phases were calculated by the elastic-plastic stress-strain finite element method (FEM), and the influences of the applied stress on the von Mises stress distribution and the coarsening regularity of g ¢ phase in a [011] oriented single crystal nickel-based superalloy were investigated. Results show that after heat treating for the [011] oriented single crystal nickel-base superalloy, the cubical g ¢ phase is embedded coherently in the g matrix, and arranges regularly along the <100> direction. When the compressive stress is applied along the [011] direction, the lattice contraction of (100)g ¢ plane along [001] and [010] directions occurs, whose extrusion action may reject the Al and Ti atoms with bigger radius, while the expansion strain on (010)g ¢ and (001) g ¢ planes takes place along the [100] orientation which may trap the Al and Ti atoms with bigger radius to promote the directional growing of g ¢ phase in the (100) plane along the [010] and [001] orientations, which is thought to be the main reason of the g ¢ phase grown directionally into the mesh-like rafted structure.