The magnetic properties of Cu-Ni, Cu-Fe and Cu-Co binary alloys prepared by ball milling and subsequent isothermal annealing have been investigated systematically. A detailed microstructural characterization by X-ray diffraction (XRD) and high-resolution transmission electron microscopic (HRTEM) analysis shows that single phase Cu-Ni solid solution formed by isothermal annealing of ball-milled Cu-Ni powder blend deteriorates the magnetic properties. In contrast, isothermal annealing of Cu-Fe and Cu-Co powder blends resulted into significant improvement of magnetic properties due to precipitation of Fe and Co from the respective supersaturated solid solution. Dispersion of Co nanoparticle in Cu matrix yielded the most attractive magnetic properties. (c) 2008 Elsevier B.V. All rights reserved.