Estudio mediante EIS de la respuesta electroquímica de la aleación AA5083 frente a señales DC anódicas
- Aballe, A. 1
- Bethencourt, M. 1
- Botana, F. J. 1
- Marcos, M. 2
- Pérez-Mariscal, J. 1
- Rodríguez-Chacón, M. A. 1
- 1 Dpto. de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica. Univ. de Cádiz. Fac. de Ciencias del Mar
- 2 Dpto. de Ingeniería Mecánica y Diseño Industrial. Univ. de Cádiz. Esc. Sup. de Ingeniería
ISSN: 0034-8570
Year of publication: 1998
Volume: 34
Issue: 0
Pages: 37-41
Type: Article
More publications in: Revista de metalurgia
Abstract
Electrochemical Impedance Spectroscopy (EIS) has been applied to characterise the behaviour of AA5083 alloy samples under anodic polarisation in a 3.5 % NaCl solution. EIS spectra were obtained at different DC potentials falling within the passivity range characteristic of the anodic polarisation branch of this alloy in the cited corrosive environment. Three different types of electrochemical response, with specific features in the corresponding Nyquist diagrams, were observed within the potential range covered in this study. The different type of spectra have been fitted with equivalent circuits. The evolution of the values of the different elements in the circuits as a function of the applied DC polarisation potential has been established. The analysis of these data has allowed us to determine the ranges of polarisation potentials where the passivation layer remains stable, metastable pits are nucleated or where stable pits grow. Finally, the use of a "Bode Surface Plot" has been proposed to get a better visualization of the evolution of the system with the applied DC potential.