Aluminum alloy toolbox welding:
(1) Select welding wire
Generally choose 301 pure aluminum welding wire and 311 aluminum silicon welding wire.
(2) Select welding method and parameters
It is generally carried out by the left welding method, and the welding torch and the workpiece form an angle of 60°. When the welding thickness is more than 15mm, the right welding method is used, and the welding torch and the workpiece form an angle of 90°.
(3) Preparation before welding
Use chemical or mechanical methods to strictly clean the surface oxide film on both sides of the weld groove.
Mechanical cleaning can use wind or electric milling cutters, scrapers, files and other tools. For thinner oxide films, 0.25mm copper wire brushes can also be used to remove oxide films.
Welding is performed immediately after cleaning. If it is left for more than 4 hours, it should be cleaned again.
(4) Features of aluminum and aluminum alloy materials in aluminum boxes
Aluminum is a silver-white light metal with good plasticity, high electrical and thermal conductivity, and also has the ability to resist oxidation and corrosion. Aluminum is easy to oxidize to produce aluminum oxide film, which is easy to produce inclusions in the weld, thereby destroying the continuity and uniformity of the metal, and reducing its mechanical properties and corrosion resistance.
(5) Difficulties in welding aluminum and aluminum alloy materials in aluminum boxes
Easy to oxidize. In the air, aluminum is easily combined with oxidation to form a dense aluminum oxide film (thickness of about 0.1-0.2μm), with a high melting point (about 2050°C), far exceeding the melting point of aluminum and aluminum alloys (about 600°C) . The density of aluminum oxide is 3.95-4.10g/cm3, which is about 1.4 times that of aluminum. The surface of aluminum oxide film is easy to absorb moisture. During welding, it hinders the fusion of basic metals and easily forms pores, slag inclusions, and defects such as non-fusion Decrease in weld performance.
Aluminum alloy is made of pure aluminum by adding some alloying elements, such as aluminum-copper alloy, aluminum-zinc-magnesium-copper super-hard aluminum alloy. Aluminum alloy has the characteristics of light weight, low cost, mechanical properties (uniform force), and aluminum alloy is easy to process and has a high degree of heat dissipation. Especially the vehicle engine part is particularly suitable for the use of aluminum alloy materials. As for most computer cases, aluminum-copper alloys are used. Mainly consider the heat dissipation problem. Because copper and aluminum are mixed and extruded, the heat dissipation performance is quite good, and even some CPU water cooling fans use this material. A box body that is made of aluminum alloy extruded material and matched with related accessories. Different from other profile boxes, this aluminum profile box has the characteristics of aluminum alloy materials, light weight, easy processing, strong load-bearing capacity, beautiful appearance, and reasonable design structure. Due to the unique characteristics of the aluminum profile box and the higher and higher technological content, it has played a better role in protecting the product in terms of convenient transportation and use, and is an ideal box for various products.