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

Hot tensile tests of the GH3625 superalloy were carried out under the temperature range of 800-1050 degrees 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 similar to 850 degrees C and 0.1 similar to 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.

Automated summary

Hot tensile tests were conducted on the GH3625 superalloy to analyze its flow behavior and investigate the effect of temperature and strain rate on grain growth. Two prediction models, the work hardening model and the modified Arrhenius model, were used to accurately predict the stress of flow curves. The best deformation condition for hot stamping of GH3625 was determined to be at temperatures of 800-850 degrees C and strain rates of 0.1-10 s(-1). A successfully hot stamped part of GH3625 was produced with improved tensile and yield strength compared to the original sheet.