Patent · US Expired

Process and apparatus for melting metals and composites while reducing losses due to oxidation

US5409580A · kind A · utility

13Cited by
11References
36Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 8, 1993
Grant dateApr 25, 1995
Priority date
Expiry dateJul 8, 2013

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC25C3/06
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A process and apparatus for melting metals that react rapidly with air at elevated temperatures to form a stable metal oxide and/or that contains a metal oxide prior to being exposed to elevated temperature, while reducing metal losses due to oxidation or the presence of the oxides. The process involves melting the metal in the presence of a molten metal salt metal salt mixture while electrolyzing metal oxide contained in the salt metal salt mixture to convert the oxide to elemental metal. The process requires an metal salt mixture which contains at least 25% by weight, and more preferably 100% by weight, of metal fluoride and which, for the metal being melted, has a composition which remains substantially unchanged during the electrolysis process. The fluoride improves oxide solubility in the metal salt mixture, making it possible to increase current densities without producing anode effects. The stable composition makes it possible to use the metal salt mixture for prolonged periods without change. The apparatus consists of a single vessel having an interior volume divided at least into a melting zone and an electrolysis zone by a heat-resistant partition which allows the metal s…

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