Fabrication and application prospects of Pr-Fe-B/Alnico nanocomposite alloys

The potentials of rare earth- based nanocomposite alloys have never been realized due to strict micro- structural constraints. Owing to the easy demagnetization it is challenging to increase the soft magnetic phase content. To avoid the easy demagnetization, Pr-Fe-B/Alnico magnets were fabricated and reported in this manuscript. The content of the Alnico phase is increased from 0 to 25 wt%, while the content of Pr element is reduced to below the sub-stoichiometry- stoichiometry of the 2:14:1 main phase. The maximum magnetic energy product, which is the figure-of-merit for permanent magnets, is increased from 122 kJ/m(3) for the standard alloy to 146 kJ/m(3) for the alloy with 15 wt% Alnico which shows a significant improvement considering the fact that the Curie point of the magnet is also increased by similar to 66 K. The special microstructure contains distinctly and heterogeneously distributed 2:14:1 and Alnico phases. The dimensions of neither the 2:14:1 nor the Alnico phases meet the dimensional requirements of the nanocomposite magnets, but still the smooth demagnetization curves are noted for the alloys. The behavior of effective anisotropy, the performance of the magnets in applied magnetic field and the magnetic interactions among the various constituent grains were quantitatively studied by reversible susceptibility, irreversible susceptibility and recoil loop openness. This study may provide some guiding principles for the development of nanocomposite magnetic alloys with excellent magnetic properties by using much less RE elements. (c) 2023 Chinese Society of Rare Earths. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.