Patent · US Expired

Compound, non-chromium conversion coatings for aluminum alloys

US6613390B2 · kind B2 · utility

3Cited by
18References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 19, 2000
Grant dateSep 2, 2003
Priority date
Expiry dateMay 21, 2021

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC23C22/73
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

The present invention relates to a compound, non-chromium conversion coating for a part formed from an aluminum alloy. The coating is formed by providing a first solution containing an anodic inhibitor species, providing a second solution containing a cathodic corrosion inhibitor species, and immersing the part to be coated in a first one of the first and second solutions and thereafter in a second one of the first and second solutions. Suitable anodic inhibitor species include tungstates, permanganates, vanadates, molybdates, and mixtures thereof. Suitable cathodic corrosion inhibitors include cobalt, cerium, other lanthanide elements, and mixtures thereof. In one embodiment, the conversion coating is formed using a cerium containing solution and a tungstate containing solution.

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