Precipitation behavior of γ' phase in superalloy FGH96 under interrupted cooling test

The precipitation behavior of gamma' phase, under various interrupt cooling tests after 1170 A degrees C, solution treatment was examined. The results indicate that the size of secondary gamma' precipitates increases with the decrease of interrupt temperature, and the shape changes from spherical to butterfly like. The fine tertiary gamma' can form either during the post cool air quenching at high interrupt-temperatures, or during the specified 5 A degrees C center dot min(-1) cooling. Air quenching at high temperatures cannot suppress further nucleation of tertiary gamma' phase.