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

Development of bulk Nd9.5Fe75.5−xMxB15 (M=Mo, Nb, Ta, Ti, and Zr; x=0–4) magnets by direct casting method

“…Recently, to overcome these disadvantages, the copper mold casting method is adopted to produce bulk amorphous precursor, followed by one-step heat treatment to optimize the magnetic properties [9][10][11][12][13]. Several research groups adopted the compositions with the extremely high B content, such as R 3-4.5 Fe bal.…”

“…Several research groups adopted the compositions with the extremely high B content, such as R 3-4.5 Fe bal. M x B 20 (R = Pr, Pr+Dy, Nd+Dy; M = Co, Cu, Mo, Nb, Ti, V, and Zr), in order to produce bulk amorphous precursor in rod form with 0.5-0.6 mm in diameter at first, and then they were annealed at 600-700 • C for 10-30 min [9][10][11][12][13] ing from the existence of considerable amount of the magnetically soft phases ␣-Fe or Fe 3 B, to suit for high temperature application [9][10][11][12][13].…”

“…Besides, it was reported that Mo, Nb, and Ta elements are helpful for increasing the glass formability. [13,19] Accordingly, the addition of Mo, Nb, Ta, Ti, V, and Zr is anticipated for refining the microstructure of directly quenched Nd 9.5 Fe 75.5 − x M x B 15 bulk magnets to simultaneously obtain higher i H c and (BH) max . To simplify manufacturing process for making isotropic magnet, in this study, we adopt the copper mold casting method to fabricate bulk NdFeMB magnets, in the rod form with a larger diameter of 0.7 mm, without any post heat treatment.…”

Magnetic property enhancement of directly quenched Nd–Fe–B bulk magnets with Ti substitution

“…To overcome these disadvantages, a new group of R-Fe-M-B (R = Pr, Pr + Dy, Nd + Dy; M = Co, Cu, Mo, Nb, Ti, V, and Zr) bulk metallic glasses have been developed by copper mold casting method, and then followed by one-step heat treatment to optimize the permanent magnetic properties [9][10][11][12][13]. The compositions with the extremely high B content, such as R 3-4.5 Nd + Dy; M = Co, Cu, Mo, Nb, Ti, V, and Zr), were adopted in order to produce bulk amorphous precursor in rod form with 0.5-0.6 mm in diameter at first, and then they were annealed at 600-700 • C for 10-30 min [9][10][11][12][13].…”

The structure and magnetic property for bulk Fe–Zr–Nd–Y–B alloys

“…Some other researches on the preparation, thermal and magnetic properties of bulk Fe-Co-RE-B (RE = Nd, Pr, Dy) magnets have been done in Refs. [8][9][10][11][12]. However, bulk amorphous alloys with more size could not be obtained due to limited glass-forming ability (GFA).…”