Rare earth permanent magnet and its preparation
US7985303B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 2010 |
| Grant date | Jul 26, 2011 |
| Priority date | — |
| Expiry date | Oct 27, 2030 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C2202/02
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.