Results are presented for the corrosion process of low carbon steel, under
the influence of the combined action of chloride and sulfate ions. The rust
composition, the corrosion rates, and the corrosion potential of the rust
layers are analyzed. An increase of the relative magnetite content as the c
orrosion rate increases was found for the long-term corrosion. The corrosio
n potential can be used to distinguish between lower and higher corrosion r
ates; more importantly a concentration (SO42- = 10(-4) M and Cl- = 1.5 x 10
(-3) M) of the pollutants where a decrease of the corrosion rate is signifi
cant was found.