S235JR steel corrosion behavior in neutral chloride media

Written by sctunisie 30 april 2017 no comments

We investigated the electrochemical behavior of S235JR steel in chloride media. The results of studying the effect of chloride concentration were reported and compared to those obtained for ordinary carbon steel (OS). Potentiodynamic polarization and cyclic voltammetry techniques were employed. For S235JR steel, it was revealed that the corrosion rate increased at higher chloride concentration and a first order kinetics was obtained. The pitting potential varied linearly with the logarithm of chloride concentration and the slope value was 110.9 mV/decade. In comparison with the ordinary carbon steel corrosion behavior, S235JR steel showed generally a better general corrosion resistance in chloride media. This was reflected by a lower value of corrosion current density equal to 8.6 mA cm^-2 compared to OS (28.3 mA cm^-2). The pitting potential determined for S235JR steel (-336 mV/SCE) was more positive than the one of OS (-365 mV/SCE) highlighting that S235JR steel is less subjected to pitting corrosion.