The aluminum veneer is made of high-quality aluminum alloy plate as the base plate, and then formed by NC bending technology. The decorative coating surface is sprayed with new curtain wall materials.
Aluminum plastic composite plate is a chemically treated aluminum coating surface material, with polyethylene plastic as the core material, which is used in the processing of special aluminum plastic plate processing equipment and composite materials. The unique nature of APCP itself determines its wide application: it can be used for building exterior walls, curtain wall panels, renovation of old buildings, interior wall and ceiling decoration, advertising signs, display racks and dust purification projects. Aluminum plastic composite board has been widely used in China and belongs to a new type of building decoration material.
1, Development history
Curtain walls have been used for decades and are still in use, including aluminum veneer, aluminum-plastic composite plate and aluminum honeycomb plate. Among the three materials, the most commonly used are aluminum veneer and aluminum plastic plate. Aluminum veneer first appeared. Later, in the late 1960s and early 1970s, APCP was invented in Germany and quickly became popular all over the world. What is the difference between aluminum and aluminum veneer? Here I will make a simple comparison between the two materials: first, the material and cost of aluminum veneer generally use 2-4mm thick AA1100 pure aluminum or AA3003 aluminum alloy plate, and 2.5mm thick AA3003 aluminum alloy plate is generally used in China; aPCP generally adopts 3-4mm three-layer structure, including upper and lower 0.5mm interlayer PVC or PE. From the material, we can see that the cost of APCP must be much lower than that of aluminum veneer. At present, the price of about 4mm thick composite plate in the market is less than 120 yuan/square meter at the price of 2.5mm thick. For 10000 square meter projects, the cost of using aluminum-plastic plate is 1.2 million yuan lower than that of using aluminum veneer.
2, Production process
At present, there are two kinds of fluorocarbon sprayed aluminum veneers and roll coating on aluminum veneers in the world. At present, there is no stick coating production line in China, so the plywood processing here mainly refers to fluorocarbon spraying production. The production of sprayed aluminum veneer is divided into two steps: the first step is sheet metal processing. This process is mainly through cutting, folding, bending, welding, grinding and other processes to process the aluminum veneer into the structure of the required shape and size. The second step is spraying. Spraying is the process of spraying paint on a metal plate. There are two types of spraying, one is manual spraying and the other is machine spraying. Machine coating is generally only suitable for the rules of flat plates, but this kind of aluminum veneer is rarely used in practice. Most domestic manufacturers use manual spraying. Manual spraying is a dangerous work, because the paint is relatively volatile and toxic, which is likely to cause chronic benzene poisoning and seriously affect human health. The advantage is that no matter the size of the aluminum-plastic coating roller is large, it must be sprayed manually to achieve a certain color. The processing of aluminum plates is more complex than that of aluminum veneer. There are four main processes: chemical forming, coating, compounding and trimming. In addition to running, these four processes are automated production. It can be seen from its treatment that aluminum-plastic plates have certain advantages in environment and safety. Coupled with the simple process of sheet metal and aluminum veneer, some private workshops have begun to get involved, which seriously affects the stable quality of the aluminum veneer market.
3, Product appearance quality and physical properties
2.5mm aluminum veneer and 4mm thick aluminum-plastic composite plate have uneven appearance quality and flatness, which looks partially concave convex, with high flatness, but the processing shape is limited; but it can be processed into various irregular shapes; the eye quality, color and film thickness deviation of spray roller coating have no obvious local color difference due to the instability of artificial technology, but the damage can not be repaired. And film thickness deviation; local damage can be repaired. Tensile strength 130 / mm 38-61n/mm2x elongation 5% - 10% 12% - 17% bending strength 84.2n/mm 34n/mm2 elastic modulus 70.00n/mm2 26.136-49.050n/mm2 from the above table, it can be seen that the appearance of aluminum veneer is worse than aluminum, but its mechanical properties are obviously better than aluminum plastic plate, and its wind pressure performance is also better than aluminum plastic plate. However, in most areas of China, the wind pressure value of aluminum plates is completely tolerable, so the use of aluminum veneer projects is a little over corrected.
4, Installation process
The installation process of aluminum and aluminum veneer is roughly the same. The biggest problem is not that the aluminum-plastic plate is processed into the required shape and size on site, with greater structural freedom. Aluminum veneer processing is formed in the factory. Due to the accuracy of domestic equipment, some small problems are often encountered in the installation process. In addition, in the installation process, the batch production of APCP is much faster than that of aluminum veneer, and the schedule assurance system is also higher.
5, Other aspects of comparison
- Lightning protection function
This issue has been debated for a long time. People really think that aluminum veneer is pure aluminum and has better conductivity. To solve this problem, German assassination GmbH has conducted lightning protection experiments of two materials in a military laboratory in Munich, Germany. The results show that at the moment of lightning stroke, the current curtain wall connection mode, whether aluminum or aluminum veneer, can completely prevent lightning stroke; when lightning strikes a continuous current, the lightning part of the metal plate or metal surface layer is easy to melt. Because the polyethylene core in the middle of the aluminum-plastic composite plate has good insulation, lightning damage is limited to the skin.
- Fire protection characteristics
Aluminum veneers don't burn, we all know. The early aluminum-plastic board was not fireproof, but with the development of aluminum-plastic board technology, fireproof aluminum-plastic composite board can be used now. Because of its non-toxic and flame-retardant PE material, the fireproof performance is greatly improved, which is completely possible to meet the needs of engineering fire.
- Residual value
Aluminum veneer has a certain residual value, but due to its high cost, the waste is still much greater than aluminum-plastic composite veneer, and there is almost no residual value. To sum up, aluminum veneer and aluminum-plastic composite plate have their own advantages, but from a large perspective, the application of aluminum-plastic plate should be more affordable and environmentally friendly.