Hot Pressed Pr2(Fe,Co)14B/PrCo5 Hybrid Magnet Prepared by Spark Plasma Sintering

PrFeB/PrCo 5 hybrid magnets were prepared by spark plasma sintering from the commercial nanograin Pr 2 (Fe,Co) 14 B powders (80wt.) and as-milled amorphous PrCo 5 powders (20wt.). X-ray diffraction of the isotropic Pr 2 (Fe,Co) 14 B/PrCo 5 hybrid magnet shows the existence of the major Pr 2 (Fe,Co) 14 B phase and the minor PrCo 5 phase. A small amount of a new Pr(Co 1-x Fe x ) 3 phase was also detected. Both coercivity and remanence values of the hybrid magnet lie between those of Pr 2 (Fe,Co) 14 B and PrCo 5 magnets. The smooth demagnetization curve of the hybrid magnet shows that the hybrid magnet retains the characteristics of a single, hard ferromagnet. The 720K Curie temperature indicates strong exchange coupling between the Pr 2 (Fe,Co) 14 B and PrCo 5 phases. The new Pr(Co 1-x Fe x ) 3 phase, due to interdiffusion between Pr 2 (Fe,Co) 14 B and PrCo 5 phases, does not affect the performance of the hybrid magnet.