Static recrystallization behavior of Inconel 718 alloy during thermal deformation

Abstract

The softening behavior of Inconel 718 alloy at different temperatures was studied using two-stage interrupted compression method on Gleeble1500D thermal stimulator, and the 2% offset method was applied to analyze the experimental dates. Finally, the static recrystallization fraction was obtained. At the same times, optical microscope (OM) and transmission electron microscopy (TEM) were employed to investigate the microstructure characteristic. The experimental results showed that the recrystallization was more sensitive to temperature than holding time. The recrystallization process finished quickly above 1 050 °C, and significantly prolonged below 1 025 °C. Additionally, the dynamical model of static recrystallization follows the Avrami equation. The nucleating mechanism was characterized by bulging at grain boundary and merging of sub-grain.

Keywords

Inconel 718 alloy / static recrystallization / nucleating mechanism

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