Aluminum is a metal that has been many useful and widely used in industry, it is used to produce aluminum alloy. Aluminum alloy can be used in many industries because of properties, such as density, and weight, it can be easily molded, not vulnerable to cracks and breakage and non-toxic to human [1], [2]. But, aluminum alloys can occur corrosion. Thus, Anodizing is the method that can reduce corrosion in natural by building the aluminum oxide film on the aluminum surface. Usually, when aluminum reacts with oxygen in the air, it occurs the stable oxide film to prevent the surface of aluminum from corrosion, and the anodizing method is also using the same principle as well [3].
Anodizing is a common method to prevent corrosion by using electrolysis that uses acid solution to react. The anodizing will change the surface of aluminum to an oxide film (Al2O3) for coating the surface to prevent the corrosion, reduce thermal conductivity and increase strength of aluminum [4]. In the process of anodizing aluminum will occur porous that orderly arrangements. The porous and oxide film can prevent the corrosion and help to dyeing color more adhesive.
The anodizing can be used in many industries such as aircraft and automobiles, these industries require materials with structures withstanding all types of weather. In addition, material on a daily basis, such as electronic devices and kitchenware is also has the anodizing [5].
The types of aluminum anodizing, have a main three types. Type I, is chromic acid anodizing, Type II is sulfuric acid anodizing, and Type III is sulfuric acid hard coat anodizing. The most common solution is sulfuric acid that is type II and other types used for other suitable applications [6]. The anodizing efficiency depends on many parameters such as type of aluminum, acid concentration, anodizing time and temperature. If we can find the best parameters, we can reduce more production costs [4].