Phase Morphology Evolution of a Single Crystal Nickel-Base Superalloy in the [011] Direction During the Tensile Creep

Abstract:

By means of finite elements analysis,an investigation has been made for the directional coarsening manners and evolutional rule of γ′ precipitates in a single crystal nickel-base superalloy with [011] orientation during tensile creep at 980 ℃ and 200 MPa. Results show that the von Mises stress in the matrix channel that is 45° with respect to the loading direction is larger than that in the matrix channel that is parallel to the loading direction when external loads applied along the [011] direction. The strain energy change in two kinds of matrix channel is the driving force for the γ′ directional coarsening, the γ′ phase developed along the [010] and [100] and perpendicular to the [001] orientations, and formed lamellar raft morphology inclined 45° angle to the tensile stress axis