Sintered magnet and rotating machine equipped with the same
US7800271B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 2009 |
| Grant date | Sep 21, 2010 |
| Priority date | — |
| Expiry date | May 15, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F41/0293
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The sintered magnet and the rotating machine equipped with the same are disclosed. The sintered magnet includes crystal grains of a ferromagnetic material consisting mainly of iron, and a fluoride compound or oxyfluoride compound layer containing at least one element selected from an alkali metal element, an alkali earth metal element, and a rare earth element. The layer is formed inside some of the crystal grains or in a part of a grain boundary part. An oxyfluoride compound or fluoride compound layer containing carbon in a stratified form is formed on an outermost surface of the crystal grains. The fluoride compound or oxyfluoride compound layer has a concentration gradient of carbon, contains at least one light rare earth element and at least one heavy rare earth element. The heavy rare earth element has a concentration lower than that of the light rare earth element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.