Phase composition and magnetic properties in nanocrystalline permanent magnets based on misch-metal

Abstract The magnetic properties and phase composition of magnets based on misch-metal (MM) with nominal composition of MM 13+x Fe 84−x B 6.5 with x = 0.5, 1, 1.5, 2 and 2.5 using melt-spinning method were investigated. For x = 1.5, it could exhibit best magnetic properties ( H cj = 753.02 kA m −1 , ( BH ) max = 70.77 kJ m −3 ). X-ray diffraction and energy dispersive spectroscopy show that the multi hard magnetic phase of RE 2 Fe 14 B (RE = La, Ce, Pr, Nd) existed in the magnets. The domain wall pinning effect and the exchange coupling interaction between grains are dependent on the abnormal RE-rich phase composition. Optimizing the phase constitution is necessary to improve magnetic properties in MM-Fe-B magnets for utilizing the rare earth resource in a balanced manner.