Disclosed is a method of preparing a micro-structured
powder for bonded magnets having high
coercivity, which is advantageous in terms of low preparation costs by recycling
magnet scraps, simplified
mass production, minimal environmental
contamination by such a recycling process, and the preparation of stable anisotropic powders having high
coercivity. Further, a
magnet powder prepared by the above method is provided. The current method is characterized in that R—Fe—B type anisotropic
sintered magnets or scraps thereof are crushed to prepare 50-500 μm sized
magnet powders, which are then mixed with 1-10 wt % of
rare earth fluoride (RF3) powders and thermally treated at high temperatures (500-1100° C.) in a vacuum or an
inert gas, to cause the change of matrix-near surface and
grain boundary of the powders. Thus obtained powders include a matrix phase having R2Fe14B
crystal structure, a R-rich
grain boundary phase containing
rare earth fluoride, and other phases, in which the matrix phase has an average grain size of 1-20 μm, and the powders have an
average size of 50-500 μm with superior magnetic characteristics of (BH)max≧20 MGOe and iHc≧5 kOe.