Rare earth bonded magnet and composition therefor
US5888417A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 1996 |
| Grant date | Mar 30, 1999 |
| Priority date | — |
| Expiry date | Oct 16, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/838
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A rare earth bonded magnet formed by bonding a rare earth magnet powder with a binding resin contains the rare earth magnet powder, and a thermoplastic resin serving as the binding resin in an amount within a range of from 1 to 5 wt. %, and preferably further contains an oxidation inhibitor. As the rare earth magnet powder, for example, at least one of an Sm--Co alloy, an R--Fe--B alloy (where, R represents at least a kind of rare earth elements including Y) and an Sm--Fe--N alloy can be appropriately used. As the thermoplastic resin, for example, polyamide, a liquid crystal polymer, or a PPS is appropriately employed. As the oxidation inhibitor, a chelating agent is appropriately applicable. In such a rare earth bonded magnet, the thermoplastic resin covers the outer surface of the rare earth magnet powder 2, and is present so as to prevent particles of the magnet powder from coming into contact with each other. Such a rare earth bonded magnet should preferably have a void ratio of no more than 2 vol. %.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.