Process for producing a rare earth-iron-boron magnet
US5167915A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 1991 |
| Grant date | Dec 1, 1992 |
| Priority date | — |
| Expiry date | Mar 27, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S264/58
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A process for producing a rare earth-iron-boron magnet, which includes the steps of: (1) charging a melt spun powder of a rare earth-iron-boron magnet into at least one cavity, which is confined by a pair of electrodes inserted into a hole of an electrically non-conductive ceramic die; (2) subjecting the melt spun powder to a non-equilibrium plasma treatment, under a reduced atmosphere of 10.sup.-1 to 10.sup.-3 Torr, while applying a uniaxial pressure of 200 to 500 kgf/cm.sup.2 to the melt spun powder in the direction connecting the electrodes interposed between a pair of thermally insulating members, thereby fusing the melt spun powder; and (3) heating the fused melt spun powder to a temperature higher than or equal to its crystallization temperature by transferring a Joule's heat generated in the thermally insulating members by passing a current through the members to the melt spun powder thereby causing the plastic deformation of the melt spun powder to form a rare earth-iron-boron magnet.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.