Process for production of ferromagnetic powder and apparatus therefor
US4141763A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 1977 |
| Grant date | Feb 27, 1979 |
| Priority date | — |
| Expiry date | Apr 5, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F1/065
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A process for producing a ferromagnetic powder comprising injecting a stream of an aqueous solution of a metal salt capable of forming a ferromagnetic substance and a stream of solution containing a reducing material for mixing into a reaction chamber such that the two solutions impinge upon one another causing an oxidation-reduction reaction between them to occur, and applying a magnetic field of 50 oe or more to the particles produced by the oxidation-reduction reaction for the period during which the particles become ferromagnetic particles after going through a superparamagnetic state and an apparatus for use in the practice of the above process comprising a reaction vessel, at least one nozzle for injecting each of a solution of a metal salt and a solution containing a reducing material into the reaction vessel and a magnet for producing a magnetic field in the reaction vessel with the nozzles being open to the magnetic field and positioned so that the solution of the metal salt and the solution of the reducing material when injected are mixed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.