Hot deformation behavior of as-cast GH4169 alloy and comparison of three constitutive models

Abstract:

In this paper, the thermal compression test of as-cast GH4169 alloy is performed on a Gleeble-1500 thermo-mechanical simulator. The deformation parameters are: temperature (1193~1373 K), strain rate (0.01~10 s_^-1), and deformation 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 are 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 were 0.891, 0.956, and 0.961, and the average relative errors (AARE) were 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.

Key words:As-cast GH4169; hot deformation behavior; constitutive model