Patent · US Expired

Production method for making rare earth compounds

US5690889A · kind A · utility

13Cited by
2References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 15, 1996
Grant dateNov 25, 1997
Priority date
Expiry dateFeb 15, 2016

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22C1/053
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A method of making a rare earth compound, such as a earth-transition metal permanent magnet compound, without the need for producing rare earth metal as a process step, comprises carbothermically reacting a rare earth oxide to form a rare earth carbide and heating the rare earth carbide, a compound-forming reactant (e.g. a transition metal and optional boron), and a carbide-forming element (e.g. a refractory metal) that forms a carbide that is more thermodynamically favorable than the rare earth carbide whereby the rare earth compound (e.g. Nd.sub.2 Fe.sub.14 B or LaNi.sub.5) and a carbide of the carbide-forming element are formed.

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