Magnetic properties of Pr-Fe-B nanocrystalline alloys for permanent magnet applications

Abstract This work investigates the influence of melt spinning fabrication processes on the phase distribution and magnetic properties of Pr 8 Fe 82 Nb 2 B 8 alloys using X-ray diffraction, magnetic thermogravimetric analysis, and vibrating sample magnetometry. The alloys were produced through melt spinning followed by rapid quenching, yielding to nanocrystalline alloys with composite microstructure comprising hard magnetic Pr 2 Fe 14 B phase as main constituent together with soft magnetic α-Fe as secondary component. Optimum processing conditions of Pr 8 Fe 82 Nb 2 B 8 alloys showed an interesting combination of magnetic properties including intrinsic coercivity of 5000 Oe together with a saturation magnetization of up to 130 emu/g, a maximum energy product of 111.92 kJ/m 3 and a Curie temperature of 388 °C. These findings highlight the critical role of processing in controlling phase composition and optimization of the magnetic performance of Pr-Fe-B alloys, in particular, the critical role of the beneficial exchange coupling interaction between hard/soft phases via nanocrystalline formation and proper phase distribution. Graphical abstract