AC-impedance measurements on aluminium barrier type oxide films

doi:10.1016/0013-4686(83)85105-6

Electrochimica Acta

Volume 28, Issue 2, February 1983, Pages 171-175

https://doi.org/10.1016/0013-4686(83)85105-6 Get rights and content

Abstract

AC-impedance measurements in the frequency range 5 × 10⁻³ Hz ≤ f ≤ 10⁴ Hz were performed in the system polycrystalline pure aluminium/0.16 M NH₄-tartrate at pH 5–7, in the potential range −900 mV ≤ E_H ≤ 400 mV. The impedance of the system is characterized by a high-frequency capacitive and a low-frequency inductive behaviour. The capacity is unequivocally related to the thickness and dielectric properties of the barrier oxide film. The faraday impedance corresponds to a metal dissolution process at the oxide film/electrolyte interphase and can be interpreted by a model previously proposed by Armstrong.

References (16)

R.D. Armstrong et al.
J. electroanal. Chem.
(1972)
R.D. Armstrong et al.
J. electroanal. Chem.
(1972)
R.D. Armstrong et al.
Electrochim. Acta
(1973)
J.W. Diggle et al.
Chem. Rev.
(1969)
S. Tajima
G.C. Wood
A.K. Vijh
(1973)
J.B. Bessone et al.
Corros. Sci.
(1981)

There are more references available in the full text version of this article.

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¹: Permanent address: Institute of Electrochemistry, Universidad Nacional del Sur, Bahia Blanca, Argentina.

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AC-impedance measurements on aluminium barrier type oxide films

Abstract

J. electroanal. Chem.

J. electroanal. Chem.

Electrochim. Acta

Chem. Rev.

Corros. Sci.