Abstract
The potentiodynamic polarization curves of Fe3Al and Fe3Al + Cr intermetallics obtained in aerated pH 4 H2SO4 acidic solution have been theoretically analyzed. The role of chromium in minimizing the hydrogen embrittlement (HE) of the intermetallic Fe3Al (resulting in its poor ductility) has been addressed based on the analysis. In the case of the chromium-alloyed iron aluminide, calculations indicate that hydrogen liberation does not occur on the surface due to the shift of the corrosion mixed potential to a value nobler than the electrode potential for the hydrogen evolution reaction. This shift occurs due to the induction of passivity on alloying with Cr resulting in the formation of a passive film. The minimization of HE of iron aluminides on alloying with Cr can thus be understood.
Similar content being viewed by others
References
Agarwal A and Balasubramaniam R 1996Bull. Mater. Sci. 19 91
Balasubramaniam R 1996Scr. Mater. 34 127
Fontana M G 1986 inCorrosion engineering 3rd ed. (Singapore: McGraw Hill Book Co.) p. 457
Liu C T, McKamey C G and Lee E H 1990Scr. Metall. Mater. 24 385
McKamey C G, Horton J A and Liu C T 1988Scr. Metall. 22 1979
McKamey C G and Liu C T 1990Scr. Metall. Mater. 24 2119
Stoloff N S and Duquette D J 1993J. Metals 45 30
West J M 1970 inElectrodeposition and corrosion processes 2nd ed., (London: Van Nostrand Reinhold Co.) p. 56–59
West J M 1986 inBasic corrosion and oxidation (Chichester: Ellis Horwood Ltd.) 2nd ed., p. 92
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Mukherjee, S., Balasubramaniam, R. Deciphering the potentiodynamic polarization curves of iron aluminides Fe3Al and Fe3Al + Cr. Bull. Mater. Sci. 19, 831–835 (1996). https://doi.org/10.1007/BF02745203
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02745203