Method of anodizing valve metals
US6267861A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2000 |
| Grant date | Jul 31, 2001 |
| Priority date | — |
| Expiry date | Oct 2, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D11/12
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method of non-thickness-limited anodizing for valve metals and alloys which are resistant to the non-thickness-limited growth of anodic oxide, such as niobium and high niobium content alloys. Non-thickness-limited anodic oxide film growth is produced on such valve metals by employing a first glycerine-based electrolyte containing about 1 to about 3 wt % water for the initial production of anodic oxide. After the substrate is anodized using the first electrolyte, it is immersed in a second glycerine-based electrolyte having less than about 0.1 wt % water. The second electrolyte may be produced by allowing water to evaporate from the first electrolyte solution until the solution contains less than about 0.1 wt. % water.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.