Mechanism of Inhibition of Corrosion of Mild Steel in Aqueous Solutions of Sodium Azelate: I. Effect of solutions of sodium azelate on the air-formed oxide film on mild steel

Abstract

Changes in the thickness and ferrous ion permeability of the air-formed oxide film on mild steel, immersed in solutions of sodium azelate, have been studied as functions of immersion time and solution pH. In neutral solutions, characteristic thickening of the air-formed oxide film takes place, whilst at lower pH values slight, but significant, film breakdown occurs during the first twenty-four hours of immersion with no detectable change thereafter. The role of azelate ions in giving rise to these different effects will be considered in Part II.