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چکیده
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The evolution of γ' phase during hot deformation has a substantial impact on the microstructures and mechanical properties of nickel-based superalloys. Accurate prediction of γ' phase content can guide process optimization and industrial production. In this study, hot compression experiments are conducted on a hot extruded FGH4113A alloy at different strain (0.22–0.92), strain rates (1–0.001 s−1), and deformation temperatures (1050–1140 ℃). The dynamic coarsening/dissolution behaviors of γ' phases in a hot extruded FGH4113A alloy during hot deformation are investigated. It is found that the deformation conditions significantly affect the morphology and distribution characteristics of the γ' phase. As the strain increases, the secondary γ' phase (γ's) gradually dissolves, while the primary γ' phase (γ'p) undergoes coarsening. An increase in deformation temperature or a decrease in strain rate promotes the dissolution of the γ's phase and inhibit the coarsening of the γ'p phase. The coarsening of the γ'p phase involves a competition between dissolution and precipitation, rather than a single precipitation process. The splitting and spheroidization mechanisms of the γ'p phase are also investigated. Based on the evolution behavior and dissolution mechanisms of γ' phases, the dynamic coarsening/dissolution kinetics models are developed for the γ' phases.
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