Study on Hot Tensile Deformation Behavior and Hot Stamping Process of GH3625 Superalloy Sheet

Abstract

Hot tensile tests of the GH3625 superalloy were carried out under the temperature range of 800–1050 °C and strain rates of 0.001, 0.01, 0.1, 1, and 10 s−1 on a Gleeble-3500 metallurgical processes simulator. The effect of temperature and holding time on grain growth was investigated to determine the proper heating schedule of the GH3625 sheet in hot stamping. The flow behavior of the GH3625 superalloy sheet was analyzed in detail. The work hardening model (WHM) and the modified Arrhenius model, considering the deviation degree R (R-MAM), were constructed to predict the stress of flow curves. The results showed that WHM and R-MAM have good prediction accuracy by evaluating the correlation coefficient (R) and the average absolute relative error (AARE). Additionally, the plasticity of the GH3625 sheet at elevated temperature drops with the increasing temperature and decreasing strain rate. The best deformation condition of the GH3625 sheet in the hot stamping is in the range of 800~850 °C and 0.1~10 s−1. Finally, a hot stamped part of the GH3625 superalloy was produced successfully, which had higher tensile strength and yield strength than the as-received sheet.

Hot deformation behavior and physical-based constitutive modelling under plane-stress state for Nickle-based superalloy sheets

“…Wu et al [21] made predictions on the uniaxial hot deformation behavior before peak stress based on the Arrhenius equation. Peng et al [22] developed a workhardening model to predict the work-hardening profile of GH3625. Wang et al [23] built an improved JC-ZA segmented structural model to predict the work hardening and softening stages of GH3128 uniaxial tensile stress-strain curve.…”