Patent · US Expired

Process for the preparation of refined tantalum or niobium

US4727928A · kind A · utility

17Cited by
8References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 8, 1986
Grant dateMar 1, 1988
Priority date
Expiry dateJul 8, 2006

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22B34/24
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Tantalum or niobium in the form of powder or pieces containing volatile impurities, e.g. sodiothermic tantalum powder, is first converted into crude cast metal by plasma melting and then the crude cast metal is refined by electron beam melting.

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