The stress relaxation behaviour of a single crystal nickel-base superalloy has been quantified using time-of-flight neutron diffraction analysis for a range of temperatures relevant to casting. A new iterative analysis methodology is described to isolate the lattice strain behaviour of the g matrix and g' precipitate phases from data obtained sufficiently rapidly to help elucidate the microscopic effect of macroscopic stress relaxation. The independent response of g and g' is revealed, showing the temperature sensitivity of lattice strain relaxation. The g/g' response is discussed in the context of thermo-mechanical conditions that may affect the propensity for recrystallisation.
- Neutron diffraction
- Stress relaxation