Effect of Cr on Strength and Conductivity Properties of Cu-0.1Zr Alloys After Aging

The Cu-Cr-Zr alloy is regarded as an optimal material for high-end electronic information industries owing to its high electrical strength, high conductivity, and outstanding softening resistance. Nevertheless, the impacts of Cr content and microstructure evolution on performance enhancement during the processing stage remain unclear. In this research, Cu-xCr-0.1Zr alloys with varying Cr contents were fabricated via the thermo-mechanical approach. The microstructure evolution, as well as the mechanical and electrical properties before and after aging were investigated. It was discovered that Cr can mitigate the grain deformation degree of the copper alloy during cold rolling, notably augment the proportion of large-angle grain boundaries, and diminish the dislocation density induced by plastic deformation. As the Cr content increases, the conductivity of the sample declines from 86% IACS (0Cr) to 34.1% IACS (1.8Cr), and the tensile strength rises from 435 MPa (0Cr) to 542 MPa (1.8Cr) after cold rolling; the conductivity decreases from 89.4% IACS (0Cr) to 77.3% IACS (1.8Cr), and the tensile strength increases from 278 MPa to 607 MPa (1.0Cr). Based on the comprehensive outcomes, the aged 1.0Cr sample, with a tensile strength of 607 MPa and a conductivity of 80.9% IACS, satisfies the performance requirements of high-strength and high-conductivity copper alloys.