| Автор | J-M Le Breton |
| Автор | S Steyaert |
| Дата выпуска | 1999-06-28 |
| dc.description | The dissociation process of the Nd<sub>2</sub>Fe<sub>14</sub>B phase in a sintered Nd<sub>16</sub>Fe<sub>76</sub>B<sub>8</sub> powdered magnet was investigated between 300 and 650 °C. The oxidized powders were characterized by Mössbauer spectrometry and x-ray diffraction. The contributions of the dissociation products to the Mössbauer spectra were identified and the results interpreted consistently with previous transmission electron microscopy observations. The microstructure of the dissociated phase was characterized and found to depend on the oxidation temperature. For temperatures less than 400 °C, the microstructure consists in -Fe nanograins (less than 10 nm in size, with a distorted structure) and Fe<sub>3</sub>O<sub>4</sub> superparamagnetic particles (size less than 10 nm), mixed with amorphous or poorly crystallized Nd<sub>2</sub>O<sub>3</sub> regions. For temperatures higher than 400 °C the microstructure consists in bigger -Fe grains (their size being 100 nm or more), Fe<sub>3</sub>O<sub>4</sub> precipitates (size less than 10 nm) and crystallized Nd<sub>2</sub>O<sub>3</sub> precipitates. It appears that the presence of additives in sintered Nd-Fe-B magnets does not change the dissociation process. Apart from some contributions in very weak proportions in Co containing samples, the same contributions are detected, owing to the same reactions. |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Название | A Mössbauer investigation of the dissociation of the Nd<sub>2</sub>Fe<sub>14</sub>B phase |
| Тип | paper |
| DOI | 10.1088/0953-8984/11/25/313 |
| Electronic ISSN | 1361-648X |
| Print ISSN | 0953-8984 |
| Журнал | Journal of Physics: Condensed Matter |
| Том | 11 |
| Первая страница | 4941 |
| Последняя страница | 4959 |
| Аффилиация | J-M Le Breton; Magnétisme et Applications, GMP UMR 6634 CNRS-Universitéde Rouen, Facultédes Sciences, 76821 Mont-Saint-Aignan Cedex, France |
| Аффилиация | S Steyaert; Magnétisme et Applications, GMP UMR 6634 CNRS-Universitéde Rouen, Facultédes Sciences, 76821 Mont-Saint-Aignan Cedex, France |
| Выпуск | 25 |
