Relation between Creep Rate during Accelerating Creep Stage and γ Channel Thickness in Single Crystal Nickel-based Superalloy, CMSX-4

Creep and Stress Relaxation Anisotropy of a Single-Crystal Superalloy

Lattice parameter misfit evolution during creep of a cobalt-based superalloy single crystal with cuboidal and rafted gamma-prime microstructures

A [h00] oriented Co-based superalloy single crystal was crept under tension at 940 C=100 MPa, resulting in a P-type raft morphology with extensive particle coalescence along the [h00] loading direction. However, particle coalescence was also observed in two perpendicular directions on the (h00) plane, normal to the loading axis. Tensile creep experiments were performed with in-situ neutron diff...

Intermediate Temperature Creep Deformation in Cmsx-3 Single Crystals

Creep deformation in < 001 > oriented single crystals of CMSX-3 has been studied at temperatures around 850°C at a stress level of 552 MPa. Detailed observations of the evolution of the dislocation structure during creep have been made. TEM stereo pairs show creep deformation in the matrix phase, leaving the 7’ precipitates undeformed. In previously undeformed crystals there is a brief incubati...

Lattice strain evolution and load partitioning during creep of a Ni-based superalloy single crystal with rafted microstructure

In-situ neutron diffraction measurements were performed on monocrystalline samples of the Ni-based superalloy CMSX-4 during N-type g0 raft formation under the tensile creep conditions of 1150 C/ 100 MPa, and subsequently on a rafted sample under the low temperature/high stress creep conditions of 715 C/825 MPa. During 1150 C/100 MPa creep, the g0 volume fraction decreased from ~70% to ~50%, the...

Recent Advances in Creep Modelling of the Nickel Base Superalloy, Alloy 720Li

Recent work in the creep field has indicated that the traditional methodologies involving power law equations are not sufficient to describe wide ranging creep behaviour. More recent approaches such as the Wilshire equations however, have shown promise in a wide range of materials, particularly in extrapolation of short term results to long term predictions. In the aerospace industry however, l...