Effect of Rotary Swaging and Subsequent Aging on the Structure and Mechanical Properties of a Cu–0.5% Cr–0.08% Zr Alloy

The effect of rotary swaging (RS) at various strains and subsequent aging at various temperatures on the structure and the mechanical properties of a Cu–0.5% Cr–0.08% Zr alloy is studied. RS is shown to form a microstructure with grains extended along the deformation axis. The grain size decreases with increasing strain. Subgrains 300–400 nm in size and shear bands 200 nm in width are observed inside the elongated grains formed upon RS at ε = 2.77. Microstructural refinement significantly increases the strength of the alloy but decreases its plasticity. Subsequent aging further increases the strength and the electrical conductivity of the alloy due to the precipitation of fine chromium and Cu 5 Zr-phase particles. Quenching, RS at ε = 2.77, and subsequent aging at 500°C for 1 h result in the best combination of strength (557 ± 18 MPa), plasticity (17.1 ± 2.6%), and electrical conductivity (83.4 ± 1.6% IACS) of the Cu–0.5%Cr–0.08%Zr alloy.