A practical method to enhance the properties of Pr/Nd-lean sintered RE-Fe-B magnets: High entropy design for RE2Fe14B

In this study, single main phase (SMP) magnets with high-entropy RE2Fe14B were prepared, which contained La, Ce, Pr, Nd and Y. The microstructure and properties of the magnets were studied. The results show that the magnets with high entropy design have a higher melting temperature (Tm) of RE2Fe14B (1189.5celcius), less REFe2 and finer grains (mean grain size: 4.51 & mu;m) compared with binary main phase (BMP) magnets of (LaCe)-Fe-B mixed with (PrNd)-Fe-B. This is mainly due to the high entropy effect, lattice distortion effect and sluggish diffusion from the high-entropy RE2Fe14B, as well as the synergism of the rare earth (RE) elements. The prop-erties of the magnets are enhanced, especially the magnetic properties. Maximum energy product (BH)max of 33.48 MGOe is achieved with only 40 wt% Pr/Nd in total RE. This work provides a valuable method to obtain RE-Fe-B magnets with high cost performance.