Hot Deformation Characteristics of Ni-Based Superalloy GH710 with Hard Deformation

The hot deformation and microstructure characteristics of GH710 alloy were investigated by thermal simulated test at the strain rates of 0.01-1 s-1 and temperatures of 1 110-1 150 ℃. The results show that metastable solid solution stare recrystallization occurred below 1 150 ℃, and γ＇phase partly dissolved into the matrix at 1 130 ℃. A hyperbolic sine function of Arrhenius was used to describe the constitutive relation for GH710 alloy with good fit accuracy, giving the hot deformation activation energy of 693.46 kJ·mol-1. The critical strain of dynamic recrystalliztion, which met a linear relationship with peak strain as εc=0.61εp, increased with increasing the strain rate and decreasing the deformation temperature. The soften mechanism of GH710 alloy was dynamic recrystallization during hot working process. According to the microstructure after hot deformation, it was proposed for GH710 alloy that proper deformation temperature range was 1 110-1 130 ℃ and proper strain rate was 0.01 s-1.