Improved tensile strength and electrical conductivity in Cu–Cr–Zr alloys by controlling the precipitation behavior through severe warm rolling

Abstract

A Cu–Cr–Zr alloy was subjected to severe warm rolling, and the effects of processing temperature and strain on the precipitation and microstructures were systematically studied. The results show that the nucleation and growth of precipitates interact with the deformation-induced defects, and therefore, the distribution precipitates vary with the different warm rolling processes. This leads to a significant impact on mechanical and electrical properties. In detail, the size of the precipitates is coarser, but the number density is lower as the applied strain (after each annealing treatment) and temperature are higher. And therefore, the UTS is lower, but the electrical conductivity is higher in rolled sheets under higher strain and temperature. Moreover, the present process could improve the comprehensive properties of Cu–Cr–Zr alloys, and an excellent combination of high UTS of 586 MPa and good electrical conductivity of 78.2%IACS was achieved in the sample of RRA ~ 723 K. (The sample was subjected to intermediate annealing treatment at 723 K between each of two rolling passes.)