Rare earth-transition metal scrap treatment method
US5087291A · kind A · utility
2Cited by
6References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 1, 1990 |
| Grant date | Feb 11, 1992 |
| Priority date | — |
| Expiry date | Oct 1, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Rare earth-transition metal (e.g. iron) scrap (e.g. Nd-Fe-B scrap) is melted to reduce the levels of tramp oxygen and nitrogen impurities therein. The tramp impurities are reduced in the melt by virtue of the reaction of the tramp impurities and the rare earth to form dross on the melt. The purified melt is separated from the dross for reuse. The oxygen and nitrogen of the melt are reduced to levels acceptable for reuse of the treated alloy in the manufacture of end-use articles, such as permanent magnets.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.