Flow behavior and microstructure evolution of FGH95 alloy formed by vacuum powder forging

Abstract

The high temperature deformation behavior of vacuum powder forging FGH95 alloy was studied by Gleeble-3800 thermal simulation testing machine. The hot compression test was carried out at the deformation temperature of 1090-1170 ℃ and the strain rate of 0.01-10 s−1. The flow stress-strain curves under the corresponding conditions were obtained. The effects of deformation conditions on the microstructure evolution of vacuum powder forging FGH95 alloy were analyzed by EBSD. After considering the influence of temperature，strain rate and strain on the flow behavior of the alloy，the Arrhenius equation was selected to establish the constitutive model of vacuum powder forging FGH95 alloy，and the parameters of vacuum powder forging FGH95 alloy were obtained. The relationship between material parameters and strain was fitted and the obtained constitutive equation was verified.The results show that the flow stress of FGH95 alloy prepared by vacuum powder forging process decreases with the increase of temperature and increases with the increase of strain rate. The size of recrystallized grains in the deformed microstructure decreases with the increase of temperature and increases with the decrease of strain rate. The error between the predicted value and the experimental value of the flow stress of the vacuum powder forging FGH95 alloy is 6.33%，and the predicted value is in good agreement with the experimental value.

Keywords

• fgh95 alloy
• high temperature deformation
• constitutive model
• dynamic recrystallization