Magnetic properties of bulk nanocomposite permanent magnets based on NdDyFeB alloys with additions

NdFeB-based bulk nanocomposite permanent magnets with addition of Mo, Ti, Zr, Cu, Nb, V, respectively, Dy substitution for Nd and Co substitution for Fe, in form of rods with diameters ranging from 0.5 to 0.8 mm, have been prepared by devitrification annealing of amorphous and partly-amorphous precursors produced by injection die casting. A fully amorphous structure was obtained for rods with the diameter as large as 0.6 mm. The best-achieved magnetic properties have been obtained for the optimum devitritication annealed Nd3Dy1Fe66Co10B20 rods with 0.6 mm diameter and are: H-i(c) = 296 kA/m, mu M-0(r) = 0.86 T, M-r/M-max = 0.65 and (BH)(max) = 74 kJ/m(3). (c) 2004 Elsevier B.V. All rights reserved.