[China Aluminum Industry Network] In addition to containing free silicon, aluminum parts also contain various compounds and other inclusions between metals. Due to the loose structure of the cast aluminum parts, there may be uneven segregation of chemical components. At the same time, the unprocessed surface will form a dense oxide film when cooled after casting. Alkali corrosion time is short, the cast aluminum may not be completely removed, and due to alkaline dissolution of cast aluminum when the dissolution rate is faster, after alkali etching will often lead to excessive corrosion of cast aluminum parts, resulting in tolerance size Changes can even cause product obsolescence.
In view of the existence of the above situation, it can be solved by changing the alkali etching procedure, that is, the alkali etching treatment is performed after the casting molding. According to this process procedure, it is possible to prevent problems such as scrapping of parts caused by alkali corrosion, and also to facilitate the surface quality after oxidation.
The above-mentioned alkali etching method can avoid over-corrosion of the parts, and after alkali etching, 1:1 hydrochloric acid can be used for rapid light emission of 2 to 3 seconds instead of the more toxic hydrofluoric acid, which is not only favorable for environmental protection, but also improves working conditions. It can also reduce production costs.
In view of the existence of the above situation, it can be solved by changing the alkali etching procedure, that is, the alkali etching treatment is performed after the casting molding. According to this process procedure, it is possible to prevent problems such as scrapping of parts caused by alkali corrosion, and also to facilitate the surface quality after oxidation.
The above-mentioned alkali etching method can avoid over-corrosion of the parts, and after alkali etching, 1:1 hydrochloric acid can be used for rapid light emission of 2 to 3 seconds instead of the more toxic hydrofluoric acid, which is not only favorable for environmental protection, but also improves working conditions. It can also reduce production costs.