Method of preparing a magnetic material
US4723994A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 1986 |
| Grant date | Feb 9, 1988 |
| Priority date | — |
| Expiry date | Oct 17, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F1/0571
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of forming a magnetic material. The magnetic material is a solid mass of grains, and has magnetic parameters characterized by: (1) a maximum magnetic energy product, (BH).sub.max, greater than 15 megagaussoersteds; and (2) a remanence greater than 9 kilogauss. The magnetic material is prepared by a two step solidification, heat treatment process. The solidification process is carried out by: (a) providing a molten precursor alloy; (b) atomizing the molten alloy through nozzle means to form individual droplets of the molten alloy; and (c) quenching the droplets of the molten alloy to form solid particles of the alloy. The solid particles have a morphology characterized as being one or more of (i) amorphous; (ii) microcrystalline; or (iii) polycrystalline. The grains within the solid have, at this stage of the process, an average grain characteristic dimension less than that of the heat treated magnetic material. In the second, or heat treating, stage of the process, the atomized solid particles are heat treated to form a solid material comprised or grains meeting at grain boundaries. The grains and grain boundaries have the morphology of the magnetic material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.