Synthesis and characterization of nanoparticles of Alnico alloys Original Research Article

Nanoparticles of Alnico 4 (Fe–12% Al–28% Ni–5% Co) and Alnico 5 (Fe–8% Al–14% Ni–24% Co–3%–Cu) alloys with the mean particle diameter from 12 to 34 nm were successfully produced by hydrogen plasma metal reaction. The particle features, oxidization behavior and magnetic properties were studied. The nanoparticles have the same crystalline structure and lattice parameter as the master alloys, and a new phase or non-equilibrium phase has not been observed. With an increase in the mean particle, the oxidization temperature and the saturation magnetization are decreased, but the coercive force is enhanced.