With the constant innovation of science and rapid development of industry, aluminum has become the most widely used nonferrous metals due to its excellent performance. Moreover, the demand for aluminum is increasing. Until now, aluminum has been applied in many areas, such as automobile industry and aircraft industry. When applied in some extreme environments, untreated aluminum and its alloy may be corroded. https://www.alfachemic.com/testinglab/services/aluminum-anodization.html