Journal of Applied Electrochemistry

, Volume 34, Issue 11, pp 1153–1158

Passivity and passivity breakdown of 304 stainless steel in alkaline sodium sulphate solutions

  • S. S. El-egamy
  • W. A. Badaway


The passivity and passivity breakdown of 304 stainless steel were investigated in 0.25 M Na2SO4solutions of pH 10. The effect of applied potential and the presence of Cl ions in the electrolyte were also studied. Different electrochemical methods such as open circuit potential measurements, polarization techniques and electrochemical impedance spectroscopy (EIS) were used. The results showed that the steel electrode passivates under open circuit conditions and also under potentiostatic control. The rate of passive film thickening under open circuit conditions follows a simple logarithmic law. Addition of Cl ion shifts the polarization curves in the active direction and above a critical chloride concentration, [Cl ] ≥ 0.15 M, pitting corrosion occurs and the pitting potential, Epit, decreases linearly with the logarithm of [Cl]. The addition of sulphate ions to the chloride-containing solutions was found to inhibit the pitting process, and at [SO2-4] ≥ 0.25 M, a complete immunity to pitting corrosion was recorded. The impedance measurements provided support for film thickening and film breakdown reactions. An equivalent circuit model which consists of a pure resistor, RΩ, in series with a parallel combination of a pure resistor, Rp, and a constant phase element, Q, was proposed to describe the electrode/electrolyte interface. The passive film thickness was found to increase with applied potential up to a critical value of 0.3 V. At higher voltages, breakdown of the passive film occured.

corrosion corrosion inhibition EIS passivation pitting stainless steel 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    C.R. Clayton and I. Olefjord; in Corrosion Mechanisms in Theory and Practice, P. Marcis and J. Oudar, Editors, p 175, Marcel Decker, New York (1995), and references therein.Google Scholar
  2. 2.
    E. De Vito and P. Marcus, Surf. Interf. Anal, 19 (1992) 403.Google Scholar
  3. 3.
    W. Wang, D. Costa and P. Marcus, J. Electrochem. Soc., 141 (1994) 111.Google Scholar
  4. 4.
    V. Maricue, W. Yang and P. Marcus, J. Electrochem. Soc., 143 (1996) 1182.Google Scholar
  5. 5.
    S.S. El-Egamy, W.A. Badawy and H. Shehata, Corrosion Prevention Control, 47 (2000) 35.Google Scholar
  6. 6.
    S.S. El-Egamy, W.A. Badawy and H. Shehata, Mat. Wiss. und. Werkstofftech, 31 (2001)737.Google Scholar
  7. 7.
    S.I. Ali and G.J. Abbaschian, Corros. Sci., 18 (1978)15.Google Scholar
  8. 8.
    H.C. Man, D.R. Gabe, Corros. Sci., 21 (1981) 713.Google Scholar
  9. 9.
    J.J. Park, S.I. Pyun, W.J. Lee and H.P. Kim, Corrosion, 55 (1999) 380.Google Scholar
  10. 10.
    A.R. Brooks, C.R. Clayton, K. Doss and Y.C. Lu, J. Electrochem. Soc., 133 (1986) 2459.Google Scholar
  11. 11.
    T. Hong, G.W. Walter and M. Nagumo, Corros. Sci., 38 (1996) 1525.Google Scholar
  12. 12.
    J.H. Wang, C.C. Su and Z. Zsklarska-Smialowska, Corrosion, 44 (1988) 732.Google Scholar
  13. 13.
    S.T. Amaral and I.L. Muller, Corros. Sci., 41 (1999) 747.Google Scholar
  14. 14.
    T. Kodoma, 5th Int. Congr. Metallic Corrosion, p. 223, NACE, Houston 1974.Google Scholar
  15. 15.
    R.P. Frankenthal and H.W. Pickering, J. Electrochem. Soc., 119 (1972) 1304.Google Scholar
  16. 16.
    Z. Szklarska-Smialowska, Corros. Sci., 18 (1978) 97.Google Scholar
  17. 17.
    A. Kolics, J.C. Polkinghorne and A. Wieckowski, Electrochim. Acta, 43 (1998) 2605.Google Scholar
  18. 18.
    M. Keddam, O. R. Mattos and H. Taken; Electrochim. Acta, 31 (1986) 1159.Google Scholar
  19. 19.
    A. L. Dobbelaar, E. C. M. Herman and J. H. W. De Wit; Corros. Sci., 33 (1992) 765.Google Scholar
  20. 20.
    D. D. Macdonald and Urquidi-Macdonald in Modification of Passive Films; P. Marcus, B. Baroux and M. Keddam, Editors, p. 46, Ins. Of Materials, London (1994).Google Scholar
  21. 21.
    D. D. Macdonald, S. R. Biaggio and H. Song; J. Electrochem. Soc., 139 (1992) 17.Google Scholar
  22. 22.
    J.R. Macdonald, “Impedance Spectroscopy” New York, N.Y., John Wiley & Sons, 1987.Google Scholar
  23. 23.
    K. Juttner, W.J. Lorenz and W. Paatsch, Corros. Sci., 29 (1989) 279.Google Scholar
  24. 24.
    U. Rammelt and R. Reinhard, Corros. Sci., 27 (1987) 373.Google Scholar
  25. 25.
    K Juettner, W.J. Lorenz, W. Paatsch, M.W. Kendig and F. Mansfeld, Werkst. und Korros., 36 (1985) 120.Google Scholar
  26. 26.
    S.C. Thomas and V.I. Birss, J. Electrochem. Soc., 144 (1997) 1353.Google Scholar
  27. 27.
    J.W. Diggle, T.C. Downie and C.W. Goulding, Electrochim. Acta, 15 (1970) 1079.Google Scholar
  28. 28.
    S.M. Abd El-Motaal, N.H. Hilal and W.A. Badawy, Electrochim. Acta, 39 (1994) 3611.Google Scholar

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • S. S. El-egamy
    • 1
  • W. A. Badaway
    • 1
  1. 1.Faculty of Science, Department of ChemistryCairo UniversityGizaEgypt

Personalised recommendations