Rare earth permanent magnets and their preparation
US10614952B2 · kind B2 · utility
1Cited by
12References
6Claims
0Family size
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Key dates
| Filing date | Mar 9, 2017 |
| Grant date | Apr 7, 2020 |
| Priority date | — |
| Expiry date | Apr 18, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F1/0577
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A sintered magnet body (RaT1bMcBd) coated with a powder mixture of an intermetallic compound (R1iM1j, R1xT2yM1z, R1iM1jHk), alloy (M1dM2e) or metal (M1) powder and a rare earth (R2) oxide is diffusion treated. The R2 oxide is partially reduced during the diffusion treatment, so a significant amount of R2 can be introduced near interfaces of primary phase grains within the magnet through the passages in the form of grain boundaries. The coercive force is increased while minimizing a decline of remanence.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.