Molebdate as Corrosion Inhibitor for Aluminium 356 In Acidic and Saline Media

Jahagirdhar A. A; Pruthviraj R. D.

Abstract

Corrosion processes are the cause of significant losses in industry. Organic, inorganic, and mixed material inhibitors have all been used to resist corrosion for a long time, but the environmental toxicity of organic corrosion inhibitors has driven a quest for inorganic corrosion inhibitors. The effect of molybdate as a new corrosion inhibitor on the corrosion of aluminium 356 in acidic and saline conditions was investigated using electrochemical and weight loss techniques. It was also looked into the effect of inhibitor concentration. The metal’s surface morphology before and after corrosion was studied using high resolution scanning electron microscopy with energy dispersive spectroscopy (HR-SEM/EDS). Experimental results revealed that molybdate in at the various concentrations studied, the investigated solution reduced the rate of corrosion. The results of the experiments using the potentiodynamic polarization method revealed that the presence of the molybdate in 3.5% NaCl. Corrosion current densities (iCORR) and corrosion rates (CR) are reduced by 0.5 M H2SO4 solutions, but polarization resistance is increased (Rp). The inhibitor efficiency was shown to be dependent on the corrosive media, inhibitor concentration, and substrate material. The adsorption characteristics of the molybdate were also described. There is a strong correlation between the outcomes of both methods.

Abstract

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