Development and Deformation Behavior of Advanced Cu-Fe-C Alloy with Dual-Phase Microstructure

An advanced Cu-Fe-C alloy with dual-phase structure was prepared by combining vacuum melting and rapid solidification. The microstructure evolution and deformation behavior of the alloy n the as-cast and rolled states were studied by OM, SEM, TEM and XRD characterization, and mechanical property measurements. The results show that when the nk.ving speed of freezing interface satisfies the relationship of V-c<V<V-p, both micro-scale and nano-scale Fe-C particles are uniformly distributed in the alloy matrix, but the range between V-c and V-p for micro-scale particles is much narrower than that of nano-scale particles. Due to the solution of Fe in the Cu matrix and the existence of Fe-C particles with different sizes, the Cu-Fe-C alloy in the as-cast state possesses a much higher work hardening exponent (n=0.3628). The phase transformation of Fe-C particles from gamma-Fe to alpha-Fe can be induced by cold rolling 80%, which can be greatly used to control and optimize the strength and deformation performance of Cu-Fe-C alloy. Although the deformability of Cu-Fe-C alloy in both the as-cast and rolled states is good, compared with the cold rolled state, the alloy in the as-cast state possesses a much better coordinative deformation performance owing to the fcc structure of Fe-C phases in this state. Additionally, according to the microstructure evolution and tensile fracture morphologies of Cu-Fe-C alloy with a dual-phase structure, the coordinative deformation and fracture models were put forward.