Thermal stability of heavily drawn Cu-0.4 wt.%Cr-0.12 wt.%Zr-0.02 wt.%Si-0.05 wt.%Mg

Cu-0.4 wt.%Cr-0.12 wt.%Zr-0.02 wt.%Si-0.05 wt.%Mg was prepared by casting, quenching, aging and cold drawing. The microstructure was studied by electron microscope and X-ray diffraction. Vickers hardness was measured for the alloy after the annealing treatment at different temperatures covering a wide temperature range from room temperature to 700 degrees C. The ribbonlike structure is replaced by gross equiaxed grains. The crystal orientation is gradually approaching the full annealed specimen and the hardness difference between longitudinal and transverse directions vanishes by recovery and recrystallization. The thermal analysis was carried out and the stored energy was calculated. The release of stored energy and the reduction of resistivity are primarily due to the decrease of dislocation density. The main strengthening effect is attributed to dislocation mechanism. (C) 2010 Elsevier B.V. All rights reserved.