Anisotropie creep behavior of a nickel-based superalloy compared with single phase nickel solid solution and γ′ phase single crystals

Abstract

The creep behavior of three different single crystal alloys with various orientations at a temperature of 1123 K was investigated. The anisotropic behavior of the nickel-based superalloy CMSX-4 has been reported recently [1–3]. These observations are compared with the anisotropic creep behavior of the isolated phases which build up the two phase superalloy. The matrix material is given by a nickel solid solution single crystal, whereas the γ′ phase is represented by the alloy Ni 75Al 22Ti 1Ta 2. A detailed analysis of the deformed samples with respect to phase nucleation and dislocation configurations has been carried out. Single phase specimens show strong dislocation interactions during primary creep, resulting in a more homogeneous distribution of activated glide planes and an increasing amount of non-screw dislocations in the secondary creep stage.