RAPIDLY-SOLIDIFIED PERMANENT MAGNET MATERIALS: FACTORS AFFECTING QUENCHABILITY AND MAGNETIC PROPERTIES IN Nd{sub 2}Fe{sub 14}B
Insight into the solidification behavior of Nd{sub 2}Fe{sub 14}B-based materials processed by rapid solidification techniques has been obtained by a systematic experimental study of the Curie temperatures of selected phases found in these materials. Nd{sub 2}Fe{sub 14}B-based materials fabricated by two disparate rapid solidification techniques, inert gas atomization (IGA) and melt-spinning, has been studied. The compositions of the starting materials have been altered with additions of the refractory elements Ti and C which are known to alter the solidification behavior of these materials. Special emphasis has been placed on trying to understand the effect of alloying additions upon the nature of the quenched glass, the distribution of the elemental additions within the Nd{sub 2}Fe{sub 14}B lattice and the evolution of the elemental partitioning with quench rate and annealing condition. The experimental Curie temperature data obtained using thermal analysis methods from the particles produced by gas-atomization is consistent with both an ejection of quenched-in refractory species from the crystalline Nd{sub 2}Fe{sub 14}B lattice and with increased crystallographic order as particle size, and hence grain size, increases. Magnetic ac susceptibility measurements performed on nominally-amorphous Nd{sub 2}Fe{sub 14}B ribbons produced by melt-spinning indicate a decrease of the Curie temperature with increasing quench rate, a result that may be attributed either to the degree of Ti/C retention in the glass or to the degree of disorder in the glass, independent of Ti/C retention.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- USDOE Office of Energy Research (ER) (US)
- DOE Contract Number:
- AC02-98CH10886
- OSTI ID:
- 759021
- Report Number(s):
- BNL-66785; KC020202; R&D Project: AS410MSD; KC020202; TRN: US0005212
- Resource Relation:
- Conference: 3RD INTERNATIONAL WORKSHOP ON MATERIALS SCIENCE (IWOMS 99), HANOI (VN), 11/02/1999--11/04/1999; Other Information: PBD: 2 Nov 1999
- Country of Publication:
- United States
- Language:
- English
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