Patent · US Expired

Chemical milling of niobium

US5201997A · kind A · utility

3Cited by
4References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 31, 1991
Grant dateApr 13, 1993
Priority date
Expiry dateDec 31, 2011

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC23F1/26
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A solution is described for the chemical milling of niobium and niobium-base alloys. The solution contains about 25% HNO.sub.3, about 19% HF, balance H.sub.2 O, with additions of citric acid and ammonium formate to control the reaction rate and provide a smooth surface finish without intergranular attack, and a small amount of a noble metal to control hydrogen absorption. A process for using the solution to mill niobium alloys is also described.

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