Reproduction of Nd-Fe-B Sintered Magnet Scraps Using a Binary Alloy Blending Technique

摘要

Nd-Fe-B sintered magnet scraps were reproduced as the corresponding sintered magnets from the ground powders (mean particle <=3 mu m) by using a binary alloy blending technique. Although the magnets re-sintered from the as-ground powders only provided poor magnetic properties, especially the observed coercivity values (approx 20 kAm~(-1)), the magnetic properties were considerably improved compared with the as-ground powders by adding an Nd-rich alloy (80 and 20 mass percent for Nd and Fe, respectively) with the mass ratio of 90 (scrap powders) to 10 (Nd-rich alloy). Typical magnetic parameters of the recovered magnets were B_r = approx 1.21 T, H(cJ) = approx 1.6 MAm~(-1) and (BH)_(max) = approx 251 kJm~(-3). It was found that the Nd-Fe-B sintered magnet scraps were reproduced as the practically usable magnets by the above process.