The kinetics of dynamic recrystallization of Cu-0.4Mg alloy

To investigate the dynamic recrystallization (DRX) behaviors of Cu-0.4Mg alloy, compression experiments with height reduction of 60% were performed in the temperature range of 500-800 °C and the strain rate range of 0.005-10 s−1 on a Gleeble-1500 thermo-mechanical simulator. The constitutive relationship between peak stress, strain rate and deformation temperature for Cu-0.4Mg alloy is established by means of the conventional hyperbolic sine equation and the activity energy of hot deformation is determined as 213.8 kJ/mol. The critical strain for DRX initiation is identified from the conventional strain hardening rate curves, and can be described as a function of Zener-Hollomon parameter (Z). The DRX kinetics model of Cu-0.4Mg alloy is established by further analysis of true stress-strain curves and by examination of microstructure. The complete DRX grain size is a power law function of Z with an exponent of −0.1949.