Organic dyes as corrosion inhibitors of commercial AA1050 aluminum alloy in sodium chloride environment

Abstract

Considering corrosion control of aluminum is of great technical, economic, environmental and aesthetical importance, the use of inhibitors is one of the promising solutions for protecting aluminum and its alloys against corrosion. The research about green corrosion inhibitors which are environmentally friendly and do not contain heavy metals or other toxic compounds has gained a large interest. This study is an effort to investigate the role of a natural organic dye, Crocin, against the corrosion of a commercial aluminum alloy AA1050, in an aggressive chloride ions environment of NaCl 0,01M, in comparison with a synthetic dye, Alphazurine A. Corrosion behavior of AA1050 specimens in NaCl 0,01M solution at room temperature was studied by investigating their electrochemical behavior in the absence and presence of the two organic dyes, using DC Corrosion techniques, Linear Polarization and Tafel Polarization. The effect of the organic dyes as corrosion inhibitors was also evaluated by mass loss measurements. Study and characterization of the morphology of the surface of the specimens, before and after the corrosion measurements, was performed using Scanning Electron Microscopy. Results obtained showed that the examined dyes have a protective action against corrosion of aluminum surface in the corrosive environment.