Temperature dependence of the lattice parameter of the γ and γ′ phases in the nickel-based superalloy CMSX-2 Part II: Neutron diffraction study of the lattice parameter mismatch

Abstract

High-resolution neutron diffraction measurements of the lattice parameter mismatch between the γ and γ′ phases of CMSX-2 superalloy are reported. Although the existence of a distribution around the lattice parameter value of each phase makes the interpretation difficult, the temperature dependence of the lattice mismatch has been deduced from room temperature to 1300°C, taking into account the tetragonal distortion of the γ′ phase. Some implications of the measurement for the behaviour of the superalloy are discussed.