Corrosion behavior of low pressure cold sprayed Zn-Ni composites coating
| Autor: | Guosheng Huang, Lukuo Xing, Xiangbo Li |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Materials science
Passivation 020209 energy General Chemical Engineering Metallurgy Gas dynamic cold spray chemistry.chemical_element 02 engineering and technology Zinc engineering.material Chloride Dielectric spectroscopy Corrosion chemistry.chemical_compound chemistry Coating Zinc hydroxide 0202 electrical engineering electronic engineering information engineering medicine engineering General Materials Science Composite material medicine.drug |
| Zdroj: | Anti-Corrosion Methods and Materials. 63:461-469 |
| ISSN: | 0003-5599 |
| DOI: | 10.1108/acmm-11-2014-1470 |
| Popis: | Purpose This paper aims to examine the performance of low-pressure cold-sprayed zinc–nickel (Zn-Ni) composites coating, i.e. whether it has the same performance as Zn-Ni alloy coating. Design/methodology/approach In this paper, Zn-Ni composites coatings containing four different nickel contents were prepared with commercial DYMET 413 low-pressure cold spraying system under the same parameters. Corrosion behaviors of four kinds of coatings were examined with potentiodynamic polarization curves and electrochemical impedance spectroscopy methods, combined with scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction. Findings Corrosion behavior of Zn-Ni composites coating is similar to Zn-Ni alloy coating. In the early stages of immersion, the anodic dissolution of zinc happens, which results in the formation of a zinc hydroxide layer. With the continuous infiltration of chloride ion, zinc hydroxide will get converted to zinc oxide, basic zinc chloride and basic zinc carbonate. The presence of nickel in coatings can prevent zinc hydroxide from converting into zinc oxide. Research limitations/implications Further research should be done on improving the deposition efficiency, as the deposition efficiency of low-pressure cold spray is lower than 30 per cent. Practical implications Low-pressure cold spray coating can be used in cyclic dry/wet conditions to prolong the life of a steel structure. Social implications Low-pressure cold spray Zn-Ni coating is an environmentally friendly anticorrosion method which can be used as an alternative of hexavalent chromium passivation coating. Originality/value Zn-Ni composite coating can be deposited on steel directly by low-pressure cold spray by mechanically mixing the powders together. The composite coating also has the same long-term anticorrosion performance as Zn-Ni alloy coating. |
| Databáze: | OpenAIRE |
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