Hot deformation and dynamic recrystallization behavior of a Cu-9Ni-6Sn-0.04Cr alloy

Abstract

Hot deformation behavior of Cu-9Ni-6Sn-0.04Cr alloy has been investigated by isothermal compression tests in the temperature range of 750 ∼ 900 ℃ and the strain rate range of 0.01 ∼ 10 s−1. By using Arrhenius equation, the activation energy Q of Cu-9Ni-6Sn-0.04Cr alloy is 218 kJ/mol. The predicted flow stresses obtained from the established constitutive equation are consistent with the experimental results for the alloy. The results indicate that proposed constitutive equation offers a high precision for predicting the hot deformation behavior of the Cu-9Ni-6Sn-0.04Cr alloy. In addition, according to the evolution of microstructures, dynamic recrystallization process is the main softening mechanism during hot deformation in Cu-9Ni-6Sn-0.04Cr alloy. Combining the characteristics of dynamic recrystallization process with Zener–Hollomon parameter value, it is shown that continuous dynamic recrystallization is the main dynamic recrystallization mechanism in the high Z value condition. Moreover, and continuous dynamic recrystallization and discontinuous dynamic recrystallization are the main dynamic recrystallization mechanisms in the middle and low Z value condition, the discontinuous dynamic recrystallization is dominated by bulging and nucleation. This study can provide reliable hot working parameters for Cu-Ni-Sn alloy fabrication.