Hot Deformation Behavior of As-cast GH4169 Alloy and Comparison of Three Constitutive Models

Thermal compression test of as-cast GH4169 alloy was performed on a Gleeble-1500 thermo-mechanical simulator at temperature of 1193-1373 K, strain rate of 0.01 similar to 10 s(-1) , and deformation of 50%. By analyzing the true stress and true strain curve, the hot deformation behavior of as-cast GH4169 alloy was studied; the correlation coefficients (R) and average relative errors (AARE) of the three constitutive models of Johnson-Cook (JC), modified Johnson-Cook (MJC) and strain-compensated Arrhenius model were compared and analyzed. The results show that the flow stress of as-cast GH4169 alloy decreases with the increase of deformation temperature and the decrease of strain rate. The correlation coefficients (R) of the JC model, MJC model and strain-compensated Arrhenius constitutive model are 0.891, 0.956, and 0.961, and AARE are 29.02%, 11.16%, and 9.31%, respectively. Therefore, the strain-compensated Arrhenius model can describe the thermal deformation behavior of as-cast GH4169 more accurately.