Alloy ingot for permanent magnet, anisotropic powders for permanent magnet, method for producing same and permanent magnet
US5383978A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1993 |
| Grant date | Jan 24, 1995 |
| Priority date | — |
| Expiry date | Feb 12, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F1/059
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An alloy ingot for permanent magnet consists essentially of rare earth metal and iron and optionally boron. The two-component alloy ingot contains 90 vol % or more of crystals having a crystal grain size along a short axis of 0.1 to 100 .mu.m and that along a long axis of 0.1 to 100 .mu.m. The three-component alloy ingot contains 90 vol % or more of crystals having a crystal grain size along a short axis of 0.1 to 50 .mu.m and that along a long axis of 0.1 to 100 .mu.m. The alloy ingot is produced by solidifying the molten alloy uniformly at a cooling rate of 10.degree. to 1000.degree. C./sec. at a sub-cooling degree of 10.degree. to 500.degree. C. A permanent magnet and anisotropic powders are produced from the alloy ingot.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.