Galvanizing steel strip in selected areas thereof
US4101345A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1976 |
| Grant date | Jul 18, 1978 |
| Priority date | — |
| Expiry date | Nov 26, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C2/024
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Mild steel strip is galvanized in selected areas only, typically on one side only of the strip, by pretreating the areas selected for absence of galvanizing to form thereon a readily chemically strippable coating of chemically hydrated compounds non-wetting in molten zinc. Preferably, the pretreatment is carried out using phosphoric acid solution to form thereon a thin coating of a composite of hydrated iron phosphates and iron hydroxides. After passing the thus-treated steel strip through the molten zinc bath and solidification of the zinc coating, the composite coating is removed by dilute mineral acid. Mild steel strip galvanized on one side using this procedure has particular utility in the automotive industry.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.