Dynamic recrystallization behavior and processing map of the Cu-Cr-Zr-Nd alloy.

Hot deformation behavior of the Cu-Cr-Zr-Nd alloy was studied by hot compressive tests in the temperature range of 650-950 °C and the strain rate range of 0.001-10 s(-1) using Gleeble-1500D thermo-mechanical simulator. The results showed that the flow stress is strongly dependent on the deformation temperature and the strain rate. With the increase of temperature or the decrease of strain rate, the flow stress significantly decreases. Hot activation energy of the alloy is about 404.84 kJ/mol and the constitutive equation of the alloy based on the hyperbolic-sine equation was established. Based on the dynamic material model, the processing map was established to optimize the deformation parameters. The optimal processing parameters for the Cu-Cr-Zr-Nd alloy hot working are in the temperature range of 900-950 °C and strain rate range of 0.1-1 s(-1). A full dynamic recrystallization structure with fine and homogeneous grain size can be obtained at optimal processing conditions. The microstructure of specimens deformed at different conditions was analyzed and connected with the processing map. The surface fracture was observed to identify instability conditions.