Effect of solid solution process on the structure and properties of Cu-Cr-Mg alloy in the aging state

In this study, Cu-Cr-Mg alloy wires were prepared by up-drawing continuous casting and multi-pass drawing. The effect of the solid solution process on the strength and electrical conductivity of the Cu-Cr-Mg alloy was investigated. The solid solution degree of Cu-Cr-Mg alloys with different solid solution processes was evaluated by XRD. The types and morphologies of nanoprecipitates of the two alloys during different thermomechanical treatments were compared by selected area electron diffraction in TEM, and the degree of recrystallization of the peak-aged Cu-Cr-Mg alloy was analyzed by EBSD. The results showed that the degree of supersaturated solid solution of the as-cast Cu-Cr-Mg alloy was comparable to that of the as-cast Cu-Cr-Mg alloy after holding at 950 ℃ for 1 h and water quenching. Meanwhile, the strength of the as-cast Cu-Cr-Mg alloy was 52.2 MPa higher than that of the solution-treated Cu-Cr-Mg alloy, and the decrease in conductivity was only 6.3% IACS. The microstructure results showed that a large number of dispersed nanoscale precipitates existed in the matrix of both alloys, and the precipitates were close in size. The results of the strengthened model calculations are also close to the experimental results. •The addition of Mg can effectively inhibit the burning loss of Cr and improve the plasticity of the rod.•The strength and conductivity of Cu-Cr-Mg alloy prepared by up drawing short process are 506.0 MPa and 75.0% IACS.•The supersaturation of the as cast state can be close to that of the solid solution state at 950 ℃.