Can anyone provide a good source of reference, or explanation please.
There is no direct relationship between electrode potential and corrosion resistance of metals. It is because the few active metals are passivated (form of corrosion resistant oxide) and others do not.
For example, in series Fe < Cr > Fe > Al >> Mg.
Definitely there should be some correlation between these properties,which are strongly related with electronic structure of atomic species making up the metallic alloys individually as well as collectively. The work function is nothing but the Fermi energy level, which is strongly affected with deformation in the surface states by the applied and/or residual stresses as well as the existence of foreign adatoms and other topographic structural defects.
Corrosion is an electrochemical reaction taking place at the surface layer, and simply involves localized or short range electron transfer from the cation species to the anion species where the electron negativity difference plays the dominant and selective role. The lost of metallic species in the form of oxides, sulfade, phosphate etc. Where, the embedding media which is mostly water plays very important role by convective currents not only carrying out the reaction products from the zone but also supply the fresh oxygen to the reaction zone. The rough surface morphology exposed to especially the compressive stresses creates reactive zones at the trough regions, where the stress concentration is much higher than the crest (hills), The stored strain energy is additive to the Helmholtz surface free energy. That means electrochemical potential of cations at the trough is much higher then the crest. That induces the surface diffusion of cations from the trough region to the crest, which results eventually deepens the trough and sharping tips like a micro cracks, and that enhances the stress concentration further in such degrees that decimation of the structure by catastrophic fracture may take place .
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