(1) surface pretreatment: chemical or physical methods are used to clean the surface of the profiles and bare the pure matrix, so as to obtain the complete and dense artificial oxide film. The surface of the mirror or no light (Ya Guang) can be obtained by mechanical means.
(2) anodization: surface treated preform, under certain process conditions, the substrate surface is anodized to form a dense, porous and strong adsorption AL203 film.
(3) sealing hole: the pore of porous oxide film formed after anodizing is closed, so that the oxide film is anti - pollution, corrosion resistant and wear-resistant. The oxide film is colorless and transparent. With the strong adsorption property of the oxide film before sealing, some metal salts are adsorbed in the membrane hole, so that many colors such as black, bronze, golden yellow and stainless steel can appear on the surface of the section.