Thick Fe3B/Nd2Fe14B nanocomposite permanent magnet flakes prepared by slow quenching

Thick permanent magnet flakes of Fe3B/Nd2Fe14B nanocomposites have been prepared directly from molten alloys by means of the low surface-velocity melt-spinning technique under a vacuum. Dependence of microstructure and magnetic properties of Nd4Fe77.5B18.5 rapidly solidified alloys have been studied as functions of pressure of a melt-spinner chamber and the surface velocity of a Cu roll. An as-spun alloy of Nd3.5Dy1Fe73Co3Ga1B18.5 obtained at a Vs=3.3 m/s under a 1.3 kPa Ar atmosphere has a thickness of 240 μm and the room temperature magnetic properties of (BH)max=131.6 kJ/m3, Br=1.15 T, and HcJ=400 kA/m.