Permanent magnet, and motor and generator using the same
US10304600B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 2, 2015 |
| Grant date | May 28, 2019 |
| Priority date | — |
| Expiry date | Jan 29, 2036 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C2202/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In one embodiment, a permanent magnet includes a sintered compact having a composition represented by the composition formula: RpFeqMrCusCo100-p-q-r-s (where R is at least one element selected from rare earth elements, M is at least one element selected from Zr, Ti, and Hf, p is 10.5 atomic % or more and 12.5 atomic % or less, q is 24 atomic % or more and 40 atomic % or less, r is 0.88 atomic % or more and 4.5 atomic % or less, and s is 3.5 atomic % or more and 10.7 atomic % or less. The sintered compact has a structure having crystal grains constituted of a main phase including a Th2Zn17 crystal phase, and a crystal grain boundary. In the structure of the sintered compact, an average grain diameter of the crystal grains is 25 micrometer or more, and a volume fraction of the crystal grain boundary is 14% or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.