Role of S2− ions on the microstructure change and the pitting behaviour of aluminum in saline solution
| Autor: | M. M. El-Deeb |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
0301 basic medicine
Multidisciplinary Materials science Constant phase element lcsh:R Analytical chemistry lcsh:Medicine chemistry.chemical_element Microstructure Electrochemistry Corrosion Ion Dielectric spectroscopy 03 medical and health sciences 030104 developmental biology 0302 clinical medicine chemistry Aluminium Pitting corrosion lcsh:Q lcsh:Science 030217 neurology & neurosurgery |
| Zdroj: | Scientific Reports, Vol 9, Iss 1, Pp 1-10 (2019) |
| ISSN: | 2045-2322 |
| Popis: | The electrochemical behaviour and the passive film microstructure of aluminum during its exposure to 3.5 wt% NaCl solution in the absence and presence of S2− ions are investigated using potentiodynamic polarization curves, electrochemical impedance spectroscopy measurements, XRD, XRF, SEM and AFM. Electrochemical measurements show that the presence of S2− ions enhances the uniform corrosion of aluminum in NaCl solution, but delay its susceptibility to the pitting corrosion. In addition, EIS analysis illustrate that the formation of more compact and protective passive layer in the presence of S2− ions compared to its rough surface in the absence of S2− ions as evidenced by the lower value of constant phase element (CPE) and higher value of phase shift (N). Cracks, non- homogenous and open large pits with high degree of roughness are clearly observed on the aluminum surface in the absence of S2− ions, compared to oriented grooves, elongated ridges with the accumulation of the corrosion products inside the pits in the presence of S2− ions. The inhibitory effect of S2− ions for the pitting corrosion of aluminum is interpreted on the basis of the change in its microstructure of the passive film in the absence and presence of S2−ions. |
| Databáze: | OpenAIRE |
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