REMANENCE ENHANCEMENT IN MECHANICALLY ALLOYED 2-PHASE ND-FE-B MAGNETIC MATERIAL

Isotropic, nanostructured, two-phase magnetic material consisting of t he hard Nd2Fe14B(2:14:1) phase and soft alpha-Fe has been prepared by mechanical alloying and a subsequent heat treatment. Due to the nanost ructure, the exchange coupling between the phases leads to a hystheres is loop which is typical for a single-phase hard magnetic material. Th e samples reveal no dip at the coercive field of alpha-Fe and the rema nent polarization is strongly enhanced compared to isotropic, single-p hase Nd-Fe-B. The influence of the phase ratio on the magnetic propert ies is discussed as well as the role of Co additions, which lead to ma ximum values of B-r = 1.15 T, mu(0)H(c) = 0.52 T and (BH)(max) = 145 k J/m(3) of the isotropic powder.