| This paper describes the routes to process conducting materials based on the Al-Mg-Zr system combining high strength (UTS=267 MPa), electrical conductivity (over 57% IACS) and heat resistance (up to 150ϗ). These properties in the alloy with 0.4 wt.% Mg and 0.2 wt.% Zr are achieved through the formation of ultrafine-grained microstructure (UFG) by thermomechanical treatment (TMT), including annealing, severe plastic deformation (SPD) via equal channel angular pressing-Conform (ECAP-C) followed by cold drawing. The mechanical strength is enhanced by the formation of ultrafine grains during ECAP-C and their additional refinement through cold drawing. Also, ECAP-C and drawing result in the material strengthening due to increased dislocation density. The annealing of the alloy prior to SPD is used to provide a good heat resistance and high electrical conductivity via formation of nanoscale Al3Zr metastable precipitates and, correspondingly decreasing the concentration of Zr atoms in the Al solid solution. |
full paper (pdf, 1312 Kb)