- Tytuł:
- Effect of Pre-Sintering on the Diffusion Treatment of HRE for Coercivity Enhancement of a NdFeB Sintered Magnet
- Autorzy:
-
Lee, M. W.
Lee, J. K.
Jang, T. S. - Powiązania:
- https://bibliotekanauki.pl/articles/355250.pdf
- Data publikacji:
- 2019
- Wydawca:
- Polska Akademia Nauk. Czytelnia Czasopism PAN
- Tematy:
-
grain boundary diffusion process
GBDP
NdFeB magnet
coercivity
pre-sintering - Opis:
- We investigated the effect of pre-sintering process on the penetration behavior of Dy in a NdFeB sintered magnet which was grain boundary diffusion treated with Cu/Al mixed Dy source. The pre-sintering of a magnet was performed at 900°C in vacuum and then the pre-sintered body was dipped in the solutions of DyH2, DyH2 + Cu, and DyH2 + Al, respectively. The dipped pre-sintered body were then fully sintered 4 hours at 1060°C followed by a subsequent annealing. The pre-sintering apparently improved the diffusivity of Dy atoms. The penetration of Dy into the magnet extended almost to 2,000 μm from the surface, about four times deeper than that of the normally sintered and diffusion treated one, when the DyH2 + Al solution was used as a Dy source. However, the resulting increase of coercivity was about 4 kOe, somewhat lower than that of the normally treated one, mostly due to excessive oxide formation that hindered to make a continuous Nd-rich grain boundary phase and a core-shell type structure.
- Źródło:
-
Archives of Metallurgy and Materials; 2019, 64, 2; 597-601
1733-3490 - Pojawia się w:
- Archives of Metallurgy and Materials
- Dostawca treści:
- Biblioteka Nauki
Artykuł