Permanent magnet and manufacturing method thereof
US9039920B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 2011 |
| Grant date | May 26, 2015 |
| Priority date | — |
| Expiry date | Sep 23, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F1/0577
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
There are provided a permanent magnet and a manufacturing method thereof enabling carbon content contained in magnet particles to be reduced in advance before sintering even when wet milling is employed. Coarsely-milled magnet powder is further milled by a bead mill in a solvent together with an organometallic compound expressed with a structural formula of M-(OR)X (M represents V, Mo, Zr, Ta Ti W or Nb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, X represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the magnet powder. Thereafter, a compact body of compacted magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius to perform hydrogen calcination process. Thereafter, through sintering process, a permanent magnet 1 is formed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.