Dy-distribution in the grains of high-energy (Nd,Dy)-Fe-B magnets
- Vacuumschmelze GmbH, Hanau (Germany)
Sintered (Nd,Dy)-Fe-B-magnets were manufactured by adding low melting RE{sub 3}Co or RE{sub 3}Co{sub 2} alloys to basic alloys with compositions close to the Nd{sub 2}Fe{sub 14}B stoichiometry. The remanent polarizations and the coercivities of sintered and annealed magnets with about 2 wt.% Dy range from 1.39 to 1.42 T and from 6.6 to 13.5 kOe, respectively. For example the magnet manufactured with an addition of 5 wt.% Dy{sub 1.5}Nd{sub 1.5}Co{sub 2} achieves a remanence of 1.42 T and a coercivity of 9.0 kOe. The energy density of this magnet amounts to 46.8 MGOe (375 kJ/m{sup 3}). The microstructure of the magnets consists of large RE{sub 2}Fe{sub 14}B-grains with dimensions up to 50 {micro}m. WDX analysis revealed that the Dy-distribution in these grains is inhomogeneous: there is no Dy in the central region, while a Dy-concentration of 5 wt.% was detected in the border region of the {phi}-grains. Adjustment of the composition and of the processing route results in magnets with a remanent polarization of 1.4 T and a coercivity of 15 kOe.
- OSTI ID:
- 186927
- Report Number(s):
- CONF-950404-; ISSN 0018-9464; TRN: IM9609%%200
- Journal Information:
- IEEE Transactions on Magnetics, Vol. 31, Issue 6Pt2; Conference: Conference on magnetism and magnetic materials, San Antonio, TX (United States), 18-21 Apr 1995; Other Information: PBD: Nov 1995
- Country of Publication:
- United States
- Language:
- English
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