Dynamics of phase transformation of Cu-Ni-Si alloy with super-high strength and high conductivity during aging

The precipitation behaviors of the Cu-Ni-Si alloys during aging were studied by analyzing the variations of electric conductivity. The Avrami-equation of phase transformation kinetics and the Avrami-equation of electric conductivity during aging were established for Cu-Ni-Si alloys, on the basis of linear relationship between the electric conductivity and the volume fraction of precipitates, and the calculation results coincide well with the experiment ones. The transformation kinetics curves were established to characterize the aging process. The characteristics of precipitates in the supersaturated solid solution alloy aged at 723 K were established, and the results show that the precipitates are β-Ni3Si and δ-Ni2Si phases.