Synergistic inhibition effect of trisodium phosphate and sodium benzoate with sodium dodecyl benzene sulphonate on the corrosion of Mg-Al-Zn-Mn alloy in 30% ethylene glycol containing chloride ions

The enhanced efficiency of the sodium dodecyl benzene sulphonate (SDBS) by the addition of trisodium phosphate and sodium benzoate on the corrosion inhibition of Mg-Al-Zn-Mn alloy in aqueous ethylene glycol solution (30%) containing chloride ions was studied by potentiodynamic polarization technique and electrochemical impedance spectroscopy method. The combination of SDBS with trisodium phosphate and sodium benzoate resulted in synergistic effects on the inhibition efficiency. The inhibition efficiencies decreased with the increase in the medium temperature. The mixture of inhibitors acted predominantly as anodic types and the adsorption of the inhibitors on the surface of the alloy obeyed Langmuir adsorption isotherm.