Rare earth based magnet
US10256016B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 2014 |
| Grant date | Apr 9, 2019 |
| Priority date | — |
| Expiry date | May 30, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F1/0577
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention provides a rare earth based magnet in which the demagnetization rate at a high temperature can be inhibited even if the amount of heavy rare earth element(s) such as Dy and Tb is evidently decreased compared to the past or no such heavy rare earth element is used. The rare earth based magnet of the present invention is a sintered magnet which comprises R2T14B crystal grains as the main phases and the crystal boundary phases among the R2T14B crystal grains. The microstructure of the sintered body is controlled by including crystal boundary phases containing at least R, T and M in the crystal boundary phases, wherein the relative atomic ratios of R, T and M are as follows, i.e., 25 to 35% for R, 60 to 70% for T and 2 to 10% for M.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.