Influence of Organic Acids on the Surface and Corrosion Resistant Behavior of Anodized Films on AA2024 Aerospace Alloys in Artificial Seawater

This study aims to evaluate the influence of dicarboxylic acids (oxalic, malonic and succinic acid) used in anodization bath on the surface and corrosion resistant performance of anodized films on AA2024 aerospace grade alloys. The surface morphology, topography, composition and structure of anodized samples were examined by scanning electron microscopy, optical profilometer, X-ray diffraction and attenuated total reflectance-infrared techniques. Characterization results revealed the effect of dicarboxylic acids addition on the anodized film's surface with important changes. X-ray Photoelectron Spectroscopic analysis confirmed the presence of carboxylic groups on the porous anodized layer processed in anodization bath containing succinic acid. The electrochemical corrosion tests specified a solid relationship between the corrosion resistance and the surface microstructure of the anodized layer processed in different dicarboxylic acids. Graphic