Morphology Evolution of γ′ Precipitates during Isothermal Exposure in Wrought Ni-Based Superalloy Inconel X-750

Abstract

The morphological evolution of γ ′ precipitates and lattice mis t with isothermal aging were closely investigated in wrought Ni-based superalloy Inconel X-750. The γ ′ morphology dramatically changes in terms of shape, distribution, coalescence and coherency at the γ/γ ′ interface. These processes and their dependence on temperature are summarized as a γ ′ morphology map together with a time-temperature-precipitation (TTP) diagram through quantifying relevant morphological parameters. The lattice mis t was measured by X-ray diffraction and is positive; it decreases from 0.6% at room temperature to 0.1% at the aging temperature. These results suggest that the morphological changes of the γ ′ precipitates are attributable to very low lattice mis t, the interaction of the elastic eld, the volume fraction of the precipitates and incoherence in γ/γ ′ interface.

Review of the Quench Sensitivity of Aluminium Alloys: Analysis of the Kinetics and Nature of Quench-Induced Precipitation

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Aging of γ′ Precipitates at 750 °C in the Nickel-Based Superalloy AD730TM: A Thermally or Thermo-Mechanically Controlled Process?

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Influence of titanium on structure formation, liquation processes and microhardness of structural components of Al – Ni – Ti alloys synthesized from the oxide phases by SHS metallurgy

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