Activation composition and method for forming adherent chromium electrodeposits on ferrous metal substrates from high energy efficient baths
US4711705A · kind A · utility
1Cited by
3References
16Claims
0Family size
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Key dates
| Filing date | Jan 15, 1987 |
| Grant date | Dec 8, 1987 |
| Priority date | — |
| Expiry date | Jan 15, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D5/36
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An activation composition and method for producing chromium electrodeposits having excellent adhesion on both soft and hardened ferrous substrates from high energy efficient chromium baths is described. The activation composition is a solution containing iodate and fluoroborate ions, optionally with cerium ion as a stabilizer. The method includes electrolytically etching the substrate in the activation solution, preceded or followed by reverse etching in chromic acid. The chromium electrodeposit can be carried out effectively to provide the desired adherent deposit from a high energy efficient (HEEF) chromium plating bath.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.