High-performance NdFeB permanent magnet produced with NdFeB scraps and production method thereof
US10468167B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 2017 |
| Grant date | Nov 5, 2019 |
| Priority date | — |
| Expiry date | Jul 14, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F41/0273
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A high-performance NdFeB permanent magnet produced with NdFeB scraps and a production method thereof are provided. The production method includes steps of: under a vacuum condition, sending a portion of raw materials, including pure iron, ferro-iron, the NdFeB scraps and rare earth fluorides, into a crucible, refining, and obtaining a first melting liquid; absorbing slags by a slag cleaning device, and moving the slag cleaning device out; sending a rest of raw materials into the crucible, refining the first melting liquid and the rest of raw materials in the crucible, and obtaining a second melting liquid; pouring the second melting liquid after refining onto a surface of a water-cooled rotation roller through a tundish, and forming alloy flakes; processing the alloy flakes with hydrogen decrepitation, milling the alloy flakes into powders by a jet mill, then magnetic field pressing, presintering and sintering.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.