Effects of different Cr contents on microstructure, mechanical and electrical properties of Cu-Zr-Cr alloy

Cu-0.3Zr-0.05Cr and Cu-0.3Zr-0.15Cr alloys were prepared by vacuum melting method, and solution treatment was carried out at 900 °C. In order to explore the best heat treatment process, the alloy was aged with different parameters. Through performance test and microstructure analysis, the following conclusions were drawn. After hot forging, 60% cold rolling, and 450 °C 120 min aging treatment, Cu-0.3Zr-0.15Cr alloy exhibited favorable performance with 180 HV hardness, 467 MPa tensile strength, 84.4% IACS electrical conductivity, and 12.1% elongation. The Cu-0.3Zr-Cr alloys showed a considerable increase in texture content and maximum texture strength as the Cr concentration rose. The primary mechanism for strengthening alloys is precipitation strengthening. During the aging treatment, Cr and Cu5Zr phases are precipitated in the alloy. The Cr phase formed a semi-coherent interface with the Cu matrix, which allowed the alloy to retain its good flexibility. The dispersed precipitates greatly increased the strength and electrical conductivity of the alloy, resulting in outstanding overall performance.