Influence of halide ions on inhibitive performance of cetyl trimethyl ammonium bromide in various concentrations of phosphoric acid for cold rolled steel

The influence of chloride ions on inhibitive performance of cetyl trimethyl ammonium bromide (CTAB) in 1.0–4.0 M of phosphoric acid (H3PO4) for cold rolled steel has been studied using weight loss and Tafel polarization techniques. The effect of acid concentration on corrosion inhibition and the effectiveness of inhibitors at 1.0–4.0 M of H3PO4 have been examined. The results reveal that a synergistic effect has been observed for CTAB with NaCl at each acid concentration. In 1.0 M H3PO4, the polarization curves show that the complex is a mixed-type inhibitor.