| The purpose of this study was to search for and evaluate the effectiveness of various inhibitors to slow down or prevent atmospheric corrosion/discoloration of the local mild steel during storage in the Arabian Gulf region. Various inhibitors were reported in the literature that can help in protection against atmospheric corrosion. Among them sodium phosphate, sodium benzoate, sodium nitrite and sodium nitrate were obtained from the local market and first tested on a simulated aqueous solution for the purpose of initial screening. In light of the results obtained, sodium phosphate and sodium benzoate were selected for examination against atmospheric corrosion of steel to be applied at 10 and 100 mM concentrations for 1 day at room temperature. Test specimens were prepared from locally produced reinforcing steel products. Exposure racks were constructed from wood to hold specimens during atmospheric exposure for different periods. Corrosion was evaluated through weight loss determination, electrochemical technique and morphological analysis of corrosion specimens using photograph and scanning electron microscopy (SEM). Atmospheric corrosion inhibition performance of sodium phosphate was better and long lasting than of sodium benzoate. Atmospheric corrosion rates of sodium phosphate treated specimens stayed low even after 6 months of exposure. Atmospheric corrosion inhibition performance of sodium benzoate, on the other hand, was inferior to that of sodium phosphate and, moreover, deteriorated faster with atmospheric exposure time loosing its inhibition effectiveness totally at the end of 3 months of atmospheric exposure. |
