There are many kinds of cast aluminum parts, so it is not necessary to choose silicon aluminum alloy. Even if Si Al alloy is selected, anodizing is not impossible. Generally speaking, the alloy aluminum contains more or less silicon, for example, 6061 contains 0.4 ~ 0.8% silicon, 7075 contains 0.4% silicon. Such silicon content has little effect on the anodization of alloy. However, when the content of silicon in the alloy is large (> 7%), it will affect the anodizing of the alloy. These problems can be solved by the process, which requires the surface treatment manufacturer to have a certain technical ability. Therefore, cast aluminum ≠ silicon aluminum alloy ≠ cannot be anodized.
Let's talk about coloring. Anodizing and coloring of aluminum alloy are two different processes, which are different from bluing of steel. The bluing of iron and steel is that the oxide film itself is blue, and coloring is carried out immediately after anodizing, and the oxide film itself is colorless and transparent. Aluminum alloy anodized with sulfuric acid is the most suitable for dyeing the oxide film. Now more and more organic dyes are used for coloring, and then the oxide film is sealed after coloring. In addition, the electrolytic coloring of heavy metal salts is also useful, but it is difficult to dye red according to the requirements of the building owner. The process of chemical treatment of iron and steel parts in phosphoric acid solution to form a protective film which is difficult to dissolve in water is called phosphating treatment.
Generally, the melting point of metal is relatively moderate in the casting of aluminum casting parts, such as aluminum, zinc and other raw materials. Through the processing equipment, various shapes of products are cast, which are applied in different fields. Due to the various casting process and complex process, this is also the main reason for the damage of die casting parts. Some manufacturers mainly test the integrity of each process of die casting, but this has become a major difficulty in the production process.
The common defect of die casting is cracking, because in the process of die casting, the stress does not meet the requirements, which will lead to casting damage, so what affects the stress?
The influence stress is mainly the energy conversion, from mechanical energy, chemical energy and heat energy to the thermal stress of the equipment. Therefore, during the production of die casting, the manufacturer should manually adjust the error of energy conversion to keep the working environment of the equipment relatively stable.
Generally speaking, the damage of die-casting products generally occurs in the processing of the later batch of products, so the staff should adjust the equipment temperature and equipment operation environment appropriately in the later processing, so as to ensure that the qualified rate of products can reach more than 98%.