Influence of Additional Micro-Sized Particles of Dy-Nd-Cu-Al on Magnetic Properties of Sintered Nd-Fe-B Magnets.

In this work, we investigated the influence of concentration of the additional micro-sized particles of DyNdAl and NdCuAl on magnetic properties of the sintered NdFeB magnets. The additional particles with size in the range of 1-3 m were prepared by ball milling method and then mixed into micrometer NdFeB master powder with different weight fractions before magnetic anisotropic pressing, vacuum sintering and annealing. The results show that the coercivity of the sintered Nd-Fe-B magnets can be improved considerably by introducing additional particles to the grain boundaries.