Aluminum is also oxidized under normal conditions so that in the presence of air and usually a layer of non-porous oxide is formed on the surfaces of aluminum parts, which is responsible for protecting the metal surface in the environment, but the advantage of the oxide created by the anodizing method is Under natural conditions, it is more resistant to corrosion. In this method, the high resistance of Al2O3 aluminum oxide coating layer against corrosion that is formed immediately on the surface of freshly cut aluminum is used. This layer is the natural corrosion resistance agent of this metal. This layer, which forms naturally, is very thin, sticky and protective. Anodizing is actually a type of thickening of the oxide layer to a thickness of several thousand times the thickness of the natural oxide layer.