| Autor: |
E. D. Specht, J. W. Herchenroeder, P. C. Canfield, J. A. Horton, L. Heatherly, D. Li |
| Rok vydání: |
1998 |
| Předmět: |
|
| Popis: |
Efforts to understand and improve the fracture toughness of Nd{sub 2}Fe{sub 14}B permanent magnets require an understanding of the fracture process itself. Cleavage plane orientations in Nd{sub 2}Fe{sub 14}B were identified by X-ray diffraction and found to be rather random. Cleavage fracture surfaces often exhibited smooth curvatures with no evidence for cleavage steps. The small grain sizes of less than 100 nm in Magnequench MQ material preclude an easy assessment of the fracture mode by scanning electron microscopy. Auger electron spectroscopy showed that much of the surface is covered with a 1 nm thick layer of a neodymium-rich phase presumably the 70Nd-30Fe eutectic phase suggesting that the hard Nd{sub 2}Fe{sub 14}B grains do not cleave but instead failure is at or in the grain boundary phase. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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