The Effect of Electrolyte Concentration and Electric Current on the Quality of Surface Coloring on Anodized Aluminum

The use of aluminum metal in daily life has widely used coloring techniques to enhance the aesthetic value of the metal. Aluminum anodizing process can produce porous on the metal surface. The formed porous can be used to store and hold the coloring agent to make them more durable. The research intends to observe the coloring characteristics on the aluminum surface influenced by several parameters of the anodizing process, including electrolyte concentration and electric current. In this study the current H2SO4 concentration was used as a variable to improve the quality of staining on anodized aluminum surfaces. The anodization process was carried out on H2SO4 electrolyte solution with variations in concentrations of 10% to 20% and the current density used was 3 A to 5 A. The tests were carried out using micro Vickers to observe the hardness value. The hardness was higher at lower concentration of electrolyte solution due to thinner layer of oxide film, scanning electron microscope to observe the structure and visual observations for anodized color quality. From the results given, the tendency of the lower current density the size and density of porous lower. With the same condition, the color was darker than higher current density.