Rare-earth magnet and method of manufacturing the same
US12217907B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Dec 1, 2021 |
| Grant date | Feb 4, 2025 |
| Priority date | — |
| Expiry date | Dec 1, 2041 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C2202/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A rare-earth magnet and a method of manufacturing the same are provided. The method includes: preparing Sm—Fe—N magnetic powder; preparing reforming material powder containing metallic zinc; mixing the magnetic powder and the reforming material powder to obtain mixed powder; subjecting the mixed powder to compression molding in a magnetic field to obtain a magnetic-field molded body; subjecting the magnetic-field molded body to pressure sintering to obtain a sintered body; and subjecting the sintered body to heat treatment. A content proportion of the metallic zinc in the reforming material powder is 10 to 30% by mass with respect to the mixed powder. When a temperature and time in conditions for the heat treatment are defined as x° C. and y hours, respectively, the formulas y≥−0.32x+136 and 350≤x≤410 are met.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.