In situ SANS investigation of the kinetics of rafting of γ′ precipitates in a fourth-generation single-crystal nickel-based superalloy

Rafting of the γ′ particles in the fourth-generation single-crystal nickel-based superalloy MC-NG was investigated in situ using small-angle neutron scattering. Rafting was induced by high-temperature annealing of a predeformed sample in the absence of applied stress. The use of extended Porod’s approximation allowed the investigation of the specific area evolution during the microstructure change. By comparison with a first-generation alloy, it is found that the alloy composition does not seem to influence the kinetics of rafting.