Method for creating a corrosion-resistant surface on an aluminum-copper alloy
US5635084A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1995 |
| Grant date | Jun 3, 1997 |
| Priority date | — |
| Expiry date | May 22, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25F3/06
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method for treating the surface of aluminum alloys hang a relatively high copper content is provided which includes the steps of removing substantially all of the copper from the surface, contacting the surface with a first solution containing cerium, electrically charging the surface while contacting the surface in an aqueous molybdate solution, and contacting the surface with a second solution containing cerium. The copper is substantially removed from the surface in the first step either by (i) contacting the surface with an acidic chromate solution or by (ii) contacting the surface with an acidic nitrate solution while subjecting the surface to an electric potential. The corrosion-resistant surface resulting from the invention is excellent, consistent and uniform throughout the surface. Surfaces treated by the invention may often be certified for use in salt-water services.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.