Synthesis and magnetic behavior of SmCo5(1−x)Fex nanocomposite magnets

SmCo 5(1−x) Fe x (x=0.2, 0.4, 0.6, and 0.7) nanocomposites were synthesized by ball milling a mixture of SmCo5 and nanosize iron powders. Composites were made using different kinds of soft ferromagnetic phase nanoparticles, either α-Fe crystallized from amorphous iron generated by sonochemical decomposition of Fe(CO)5, or acicular metallic iron particles with an average length of 200 nm and average diameter of 18 nm. After milling the powder mixtures were compacted by hot isostatic pressing at 3000 psi for ∼5 min at a temperature of 530–570 °C. The compacted solids were magnetically characterized between 5 and 300 K. Hysteresis loop measurements and recoil measurements for the (SmCo5)0.8/acicular-Fe0.2 composite show stronger magnetic coupling when compared with the properties of (SmCo5)0.8/amorphous-Fe0.2, am-Fe coated SmCo5, and pure SmCo5 powders alone.