Effect of long-term aging on γ' phase and lattice constant of FGH95 P/M Ni-based superalloy

The effect of long-term aging on the γ' phase and lattice constant of FGH95 P/M Ni-based superalloy was investigated by microstructures observation and X-ray diffraction analysis. The results show that, after long-term aging at 450 and 550, th℃ e fine γ' phases in the full heat-treated FGH95 alloys are slightly grown up, in accordance with the coarsening kinetics in Lifshitz, Slyozov, and Wagner (LWS) theory. With the extension of aging time, the lattice constants of γ' phase in FGH95 alloys increase, while the lattice mismatches of the γ and γ' two phases decrease. Compared with the aging time, the aging temperature has a greater influence on the γ' phase size and lattice constant of the FGH95 alloy.