Modeling of flow stress constitutive behavior of GH2984 superalloy for the prospective 700 °C fossil power plant

Due to its excellent creep rupture strength and low cost, superalloy GH2984 has becoming a promising material to be used as heat exchanger in the prospective 700 °C fossil power plant. The mechanical response of the material under various forming conditions, which is a particularly important indicator for the superalloy, strongly depends on the forging temperature and strain rate. In current study, based on the measured stress-strain curves under different temperatures and strain rates, a series of flow stress constitutive equations for GH2984 superalloy were established through the classical theories on work hardening and softening. The comparison between the experimental and modeling results has confirmed that the established constitutive equations can correctly describe the mechanical responses and microstructural evolutions of the GH2984 under various hot deformation conditions.