Increase of Coercivity and Composition Distribution in Fluoride-Diffused NdFeB Sintered Magnets Treated by Fluoride Solutions
| Autor: | Matahiro Komuro, Hiroyuki Suzuki, Yuichi Satsu |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Materials science
Sintering Rare-earth magnet engineering.material Coercivity equipment and supplies Electronic Optical and Magnetic Materials chemistry.chemical_compound Neodymium magnet Coating chemistry Remanence engineering Grain boundary Electrical and Electronic Engineering Composite material Fluoride |
| Zdroj: | IEEE Transactions on Magnetics. 46:3831-3833 |
| ISSN: | 1941-0069 0018-9464 |
| DOI: | 10.1109/tmag.2010.2064780 |
| Popis: | Rare-earth and fluorine were diffused along grain boundaries in NdFeB sintered magnets during heat treatment after rare-earth fluoride liquid coating. In the case of Dy fluoride coating, the coercivity for NdFeB sintered magnets with a thickness of 1 mm after the diffusion was increased from 0.80 MA/m to 1.13 MA/m (41%) with remanence reduction of 0.6%. Segregations for Dy atoms near the grain boundaries and fluorine atoms at the grain boundary were found by TEM observations. The increase of coercivity per the weight of the rare-earth fluorides has a correlation with the anisotropy field of the RE2Fe14B (RE is rare-earth elements). Furthermore, the Dy quantity required for the observed increase of coercivity can be reduced to 1/3 compared to the previous NdFeB sintered magnets using the fluoride coating and diffusion process. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|