Materials & Design (Oct 2019)
Mechanism of interaction between the Cu/Cr interface and its chemical mixing on tensile strength and electrical conductivity of a Cu-Cr-Zr alloy
Abstract
Deformed CuCr alloys have high strength and high electrical conductivity and are used in highly-pulsed magnetic field coils, power vacuum fuses, and so on. In this paper, Cu-Cr-Zr alloy ingots were prepared by medium-frequency induction smelting. They then underwent a heat treatment, forging, cold drawing, and intermediate annealing to obtain a fiber material with a diameter of 0.8 mm. The Cu/Cr interface, precipitated phase, and Cu/Cr chemical mutual solution zone were observed by transmission electron microscopy. The mechanism by which the Cu/Cr interface affected the Cu-Cr-Zr alloy tensile strength was analyzed. The influence of chemical mixing of the Cu/Cr interface on the conductivity of the Cu-Cr-Zr alloy was also studied. The results showed that the Cu/Cr semi-coherent interface inhibited the formation of dislocations during large deformation, which gave the Cu-Cr-Zr alloy its high strength. Elimination of chemical mixing at the Cu/Cr interface allowed the conductivity of the Cu-Cr-Zr alloy to remain unchanged after extremely large deformation. Keywords: CuCr alloy, Interface structure, Chemical mixing, Conductive mechanism, Strengthening mechanism