Studying the Corrosion Resistance of Anodized Low Carbon Steel in Alkaline Solution

Abstract

Low carbon steels are widely used materials in industrial application due to its availability and properties. Therefore it always needs to improve its properties especially corrosion resistance. One of the most important methods for improving its corrosion resistance is anodizing process. This study involves anodized of low carbon steels in 1 M sodium hydroxide (alkaline) electrolyte for 30 minute, using constant current technique at a range of (20-620) mA/cm2.Atomic force microscope (AFM) used to investigate the topography and anodic film parameters, it was found that the roughness of the anodic film is mainly depend on the anodizing current density and its increase from 0.9 (as polished) to (0.281-0.598) nm after anodizing. Coating thickness also increases with an increase in current density supply to the range of (2.5-13.3) μm. The corrosion behaviors of anodized and non-anodized of low carbon steel specimens in sea water are obtained. The corrosion current density and corrosion rate are decreased with an increase in anodic current density which increases anodic film thickness.