Typical characteristics for creep fracture cleavage plane of nickel-based single crystal

Typical characteristics for creep fracture cleavage plane of nickel-based single crystal were investigated through the experimental observations. The results suggest that the topological shape of cleavage planes is related to the crystal graphical orientation. The cleavage surface exhibit four-fold symmetric in [001]orientation, two-fold symmetric in [011]orientation, and triple-symmetric in [111]orientation. It is proved that the topological morphology is associated with the stress field near void through crystal plasticity finite element method. Void size dependence and external stress magnitude dependence of cleavage plane morphology was studied as well. The void size and external stress magnitude have a significant effect on the magnitude of the axial strain, but do not change visually with respect to the distribution of axial strain. The formation of typical characteristics of cleavage plane was discussed by the slip systems activation. The characteristics of dislocation motion around the void were described by molecular dynamics simulation.