| Autor: |
P.J. McGuiness, X.J. Yin, I.R. Harris, M.J. Wyborn, X.J. Zhang, K.G. Knoch |
| Rok vydání: |
1992 |
| Předmět: |
|
| Zdroj: |
Journal of Magnetism and Magnetic Materials. :1169-1170 |
| ISSN: |
0304-8853 |
| Popis: |
The recently developed HDDR process has now been extended to production of hot-pressed magnets. The samples prepared to date exhibit intrinsic coercivities of ≈1200 kA/m, remanence of around 690 mT and BHmax values of ≈90 kJ/m3. Careful studies of the microstructures reveal that the magnets consist of Nd2Fe14B grains predominantly in the range 0.1 μm⩽x⩽1.0 μm with a very small number of grains in the range 10 μm ⩽x⩽35 μm. These larger grains exhibit a very regular morphology and appear to be the result of a very rapid growth of some of the smaller sub-micron grains. The starting composition of the cast material Nd16Fe76B8 ensures that the magnets have ≈12% Nd-rich intergranular material; this low melting point phase has been found to assist in the densification process. However, SEM studies have shown that the Nd-rich material is very unevenly distributed throughout the hot-pressed magnet and little evidence can be found for its presence between the grains of Nd2Fe14B. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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