Patent · US Expired

Method of preparing a magnetic material

US4715891A · kind A · utility

6Cited by
5References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 17, 1986
Grant dateDec 29, 1987
Priority date
Expiry dateOct 17, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01F41/22
  • 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 controlled vaporization of precursor elements of the alloy into an inert atmosphere, with subsequent controlled vapor phase condensation. This may be accomplished by vaporizing a precursor type alloy in a plasma torch, such as an argon torch, a hydrogen torch, or other electro-arc torch to form a particulate fine grain alloy. The resulting product of this alternative method is a particulate fine grain 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 fine grain solid particle…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.