Development of cost-effective nanocrystalline multi-component (Ce,La,Y)-Fe-B permanent magnetic alloys containing no critical rare earth elements of Dy, Tb, Pr and Nd

Here we first report the fully abundant rare earth (RE)-based nanocrystalline multi-component (Ce,La,Y)Fe-B alloys containing no critical RE elements of Nd, Pr, Dy, and Tb by melt-spinning technique. The roles of La and Y substitutions for Ce have been fully understood. La plays a positive role on both thermal stability and room-temperature (RT) magnetic properties. The enhanced coercivity H-cj by partial substitution of La is attributed to the increases of anisotropy field H-A and the formation of continuously distributed grain boundaries resulting from the suppression of CeFe2 phase. Although Y substitution is not benefit for H-cj, both remanent polarization J(r) and thermal stability have been effectively improved since Y2Fe14B shows relatively high saturation magnetization M-s and a positive temperature coefficient of H-A over a certain temperature range. In addition, RE element segregation has been confirmed, La prefers to enter into the grain boundaries than Ce and Y prefers to remain in the 2:14:1 phase. Based on these understanding, a series of melt-spun (Ce,La,Y)-Fe-B alloys have been designed. A relatively good combination of magnetic properties with maximum energy product (BH)(max)=7.4 MGOe, H-cj=400 kA/m, and J(r)=0.63 T has been obtained in [(Ce0.8La0.2)(0.7)Y-0.3](17)Fe78B6 alloy, together with high Curie temperature (T-c=488 K) and low temperature coefficients of remanence (alpha=-0.255 %/K) and coercivity (beta=-0.246 %/K). (C) 2021 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

The study reveals that La and Y have positive effects on room-temperature magnetic properties and thermal stability, with La substitution enhancing coercivity and Y substitution improving remanent polarization and thermal stability.