METHOD FOR OBTAINING HIGH-COERCIVITY MAGNETS FROM ALLOYS ON BASIS OF Nd-Fe-B Russian patent published in 2013 - IPC H01F1/53 H01F41/02 

FIELD: metallurgy.

SUBSTANCE: method is implemented by diffusion annealing of sintered magnets at the temperature of 600-1000°C, the surface of which contacts disperse powders of materials - diffusion sources, on the basis of dysprosium and/or terbium. As diffusion sources, disperse powders of metallic dysprosium (Dy) or terbium (Tb), powders of Dy and/or Tb hydrides, or alloys on the basis of RmTn intermetallic compounds with low fusion temperature of (500-1200°C) are used, where R-Dy or Tb; T - Co, Fe, Ni, Al, Cu, Ga or their combination and m>n (i.e. content of Dy or Tb is at least 50 at %). Diffusion annealing is performed during 0.5-20 hours at the temperature of 550-850°C, with further additional annealing at the temperature of 550-600°C during 0.5-1.0 h.

EFFECT: increasing coercitive force of sintered Nd-Fe-B magnets, without sufficient reduction of their residual induction and maximum energy product.

4 tbl, 5 dwg