Aluminum type
Aluminum belongs to one of the non-ferrous metals in the metal category. Because of its wide application, it is introduced separately as follows: Aluminum profiles and die-casting aluminium alloys are commonly used. Aluminum ingots with purity up to 92% are the main raw materials, and metal elements such as carbon, magnesium, silicon and sulfur are added to increase strength, hardness and wear resistance to form a variety of "alloys".
1.1 Aluminum Profile
Aluminum profiles such as screens and windows are common. It uses extrusion forming technology, that is, aluminium ingot and other raw materials are melted in the furnace, then extruded to die by extruder. It can also extrude various sections of profiles. The main properties, such as strength, hardness and wear resistance, are in accordance with the national standard GB6063. Advantages are: light weight only 2.8, no rust, fast design change, low input of die, vertical elongation as high as 10 meters. The appearance of aluminium profiles can be divided into bright and dumb light. The treatment process of aluminium profiles is anodic oxidation. The oxide film on the surface of aluminium profiles can reach 0.12m/m thickness. Aluminum profile wall thickness is selected according to product design optimization. It is not the thicker the better in the market. It should be designed according to the requirements of section structure. It can be uneven in 0.5-5 mm. The layman's view that the thicker the harder, in fact, is wrong.
The surface quality of aluminium profile also has some defects which are difficult to overcome: warping, deformation, black line, convex and concave and white line. The high level of designer and reasonable design and production process of die can avoid the above defects not obvious. Inspection defects should be carried out according to the inspection methods prescribed by the state, that is, the visual distance of 40-50CM to identify defects.
Aluminum profiles are widely used in furniture: screen skeleton, various suspension beams, table feet, decorative strips, handles, wiring grooves and caps, chair tubes and so on, which can be used in a variety of design and application!
Although aluminium profiles have many advantages, there are still some unsatisfactory aspects:
Unoxidized aluminium is easy to rust, which leads to performance degradation. Longitudinal strength is not as good as that of iron products. The wear resistance of surface oxide layer is not as good as that of electroplating layer, which is easy to scratch. The cost is higher, and the cost is about 3-4 times higher than that of iron products.
1.2 Die Cast Aluminum Alloy
Compared with the processing methods of die casting alloys and profiles, the equipment used is different. Its raw materials are aluminium ingots and alloy materials, which are melted in the furnace and then molded in the die casting machine. Die-cast aluminium products can be designed like toys, with different shapes and convenient connection in various directions. In addition, it has high hardness and strength, and can be mixed with zinc to form zinc-aluminium alloy.
Die-casting aluminium forming process is divided into:
1. Die-casting
2. Remaining material of rough polishing and de-closing
3. Fine polishing
On the other hand, in the production process of die-casting aluminium, there should be a mould to manufacture. The cost of the mould is very high, which is higher than other moulds such as injection moulds. At the same time, die maintenance is very difficult, and it is difficult to reduce material to repair when design errors are made.
Defects of die-casting aluminium:
The cost is low only when the quantity of production and processing is large. The cost of polishing products with complex production cycle and slow production cycle is about 3-4 times higher than that of injection parts. Screw hole requirements should be a little larger connection force to stabilize the scope of application: platform foot, platform connectors, decorative head, aluminum profile seals, countertops and tea table top brackets, etc., a very wide range.