Investigation the Mild and Hard Anodizing of 1100 Aluminium Alloy in Different Acidic Electrolyte, and Characterization of Obtained Oxide Film

Nowdays, AAO (Anodic Aluminium Oxide) films obtained by anodizing, have vast  applications in different fields of nano. In this study, AAO films production by mild and hard anodizing of 1100 aluminium alloy was investigated in three different conditions, and the characteristic parameters of these films were studied. Results showed that AAO films produced in oxalic acid and sulfuric acid mixture as an anodizing electrolyte needs to lower voltage compared with films produced in oxalic acid electrolyte alone. Mixture of oxalic acid and sulfuric acid generated AAO films with smaller interpore distance and pore diamaeter without any reduction in oxide film quality. Thickness of the barrier layer which is an important parameter for the growth of materials, was also reduced from 155 nm to about 110 nm. Phase analysis results using XRD patterns showed amorphous-crystalline structure of AAO films. EDS results showed the presence of sulfur in these films with addition of sulfuric acid to the anodizing electrolyte, and the more sulfuric acid was added to the solution, the amount of sulfur was increased. This shows high acidic potential of sulfuric acid and its peneteration into the film during anodizing process.