Structural and magnetic property changes during mechanical alloying of Fe, Co, and Cu have been studied by using X-ray diffractometry (XRD), Mössbauer experiment and magnetometry. Supersaturated fee solid solutions of Cu 50Fe 50-xCo x (x = 0, 10, 20, 40) and Cu 80Fe 20-y/Co y (y = 2, 4, 6, 8, 10, 12) have been prepared by mechanical alloying process starting from elemental components. ... [Show full abstract] Magnetization of Cu 50Fe 50-xCo x solid solution can be described mainly by ferromagnetism even though paramagnetic phase of about 12% coexists in the alloy. The variations in magnetization with Co content in supersaturated Cu 50Fe 50-xCo x and Cu 80Fe 20-yCo y solid solutions were similar to the Slater-Pauling curve, indicating presence of Fe-Co atomic clusters. The magnetization behaviour of the supersaturated solid solutions showed a mixture of superparamagnetic and ferromagnetic behaviour.