Aluminum is the most widely used and widely used metal material in non-ferrous metals, and its application range is still expanding. There are more than 700,000 kinds of aluminum products produced by using aluminum materials. According to statistics, there are more than 700,000 kinds of aluminum products, and various industries such as construction and decoration industry, transportation industry, aerospace industry, etc. have different needs.
The advantages and characteristics of aluminum are as follows:
1. Low density. The density of aluminum is about 2.7 g/cm3. Its density is only 1/3 that of iron or copper.
2. High plasticity. Aluminum has good ductility and can be made into various products by pressure processing methods such as extrusion and stretching.
3. Corrosion resistance. Aluminum is a highly negatively charged metal, and a protective oxide film will be formed on the surface under natural conditions or anodization, and it has much better corrosion resistance than steel.
4, easy to strengthen. Pure aluminum is not very strong, but it can be increased by anodizing.
5. Easy surface treatment. Surface treatments can further enhance or alter the surface properties of aluminum. The aluminum anodizing process is quite mature and stable in operation, and has been widely used in the processing of aluminum products.
6. Good conductivity and easy to recycle.
Processing technology of aluminum products
- Punching of aluminum products
1. Cold punch
Use material aluminum pellets. The extrusion machine and die are used for one-time molding, which is suitable for cylindrical products or product shapes that are difficult to achieve by stretching process, such as oval, square, and rectangular products.
The tonnage of the machine used is related to the cross-sectional area of the product. The gap between the upper die punch and the lower die tungsten steel is the wall thickness of the product. When the upper die punch and the lower die tungsten steel are pressed together, the vertical gap to the bottom dead center is For the top thickness of the product.
Advantages: The mold opening cycle is short, and the development cost is lower than that of the drawing mold.
Disadvantages: The production process is long, the product size fluctuates greatly in the process, and the labor cost is high.
2. Stretching
Use material aluminum skin. It is suitable for non-cylindrical bodies (aluminum products with curved products) to be deformed many times by using continuous die machines and molds to meet the requirements of the shape.
Advantages: more complex and multiple deformation products have stable dimensional control in the production process, and the product surface is smoother.
Disadvantages: high mold cost, relatively long development cycle, and high requirements for machine selection and precision.
- Surface treatment of aluminum products
1. Sandblasting (Shot Peening)
The process of cleaning and roughening metal surfaces using the impact of high-speed sand flow. The surface treatment of aluminum parts in this method can obtain a certain degree of cleanliness and different roughness on the surface of the workpiece, so that the mechanical properties of the workpiece surface can be improved, thus improving the fatigue resistance of the workpiece and increasing the gap between it and the coating. The adhesion of the coating prolongs the durability of the coating film, and is also conducive to the leveling and decoration of the coating.
2. Polishing
Using mechanical, chemical or electrochemical action to reduce the surface roughness of the workpiece to obtain a bright, flat surface processing method.
3. Drawing
Metal wire drawing is the manufacturing process of repeatedly scraping an aluminum sheet out of lines with sandpaper. Drawing can be divided into straight drawing, random drawing, spiral drawing, thread drawing.
4. High gloss cutting
5. Anodizing
6. Two-color anode
Process to reduce deformation in aluminum processing
There are many reasons for the deformation of aluminum parts, which are related to the material, shape of the part, and production conditions. There are mainly the following aspects: deformation caused by internal stress of blank, deformation caused by cutting force and cutting heat, and deformation caused by clamping force.
Process measures to reduce processing deformation:
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1. Reduce the internal stress of the blank
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2. Improve the cutting ability of the tool
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3. Improve the clamping method of the workpiece
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4. Reasonable arrangement of processes
