Corrosion characteristics of chromated zinc in sodium chloride solutions
- Inst. of Chemistry, Vilnius (Lithuania)
The corrosion behavior of zinc with a chromate conversion coating containing {approximately}0.02 g/m{sup 2} Cr(VI) was investigated. X-ray photoelectron spectroscopy (XPS) showed Cr(VI) was located in layers near the surface of the coating. Corrosion current densities and Cr(VI) content in the coating decreased with immersion time. An electrochemical reduction of Cr(VI) to Cr(III) parallel to oxygen (O{sub 2}) reduction in the first stages of immersion was reviewed. Inhibition of the corrosion rate proceeded simultaneously with dissolution of the conversion coating. It was concluded that the thickness of the coating was not the most important factor to hinder O{sub 2} reduction. Corrosion inhibition was attributed to zinc surface passivation byproducts of ionization.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 449640
- Journal Information:
- Corrosion, Journal Name: Corrosion Journal Issue: 2 Vol. 53; ISSN 0010-9312; ISSN CORRAK
- Country of Publication:
- United States
- Language:
- English
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