Synthesis, matching and deconstruction of polarization curves for the active corrosion of zinc in aerated near-neutral NaCl solutions

SYMADEC 1, used previously to synthesise, match and deconstruct polarization curves for the Fe/H2O/H+/O2(4e−) corrosion system, has been updated to SYMADEC Multimetal. The polarization curve of a zinc anode alloy corroding with formation of a non-protective layer of ZnO in fully-aerated, near-neutral NaCl solution was modelled. To test the SYMADEC Multimetal model four published polarization curves of zinc actively corroding in similar salt solutions are deconstructed. The polarization curve current/voltage contribution from the ZnO reduction/oxidation peak overlaid on the polarization curve is estimated by a bi-Gaussian relationship.