Aluminium Repair

Aluminum is not a new metal in the automotive industry. Some cars from the 1930s had already body parts made of aluminum. The use of aluminum in the automotive industry reduces the weight of vehicles and at the same time it is a very strong metal. The lower weight affects on the braking system and the dynamic speed of cars.

The natural properties of aluminum alloy also have a positive effect on torsion. A car made of aluminu m is easier to drive, easier to control on corners. In addition, aluminum absorbs the force of the impact, with the deformation of the body in the place where the impact was made. This property allows for maximum preservation of the vehicle's frame, thereby preserving the lives of the passengers.

The exterior aluminum body panels are made of heat-treated aluminum. This aluminum varies in hardness from T0 (very soft and ductile) to T6 (so hard that when you try to bend a piece made of this aluminum, it will break). Most exterior aluminum body panels are T4 hardness. They are hard enough and resistant to dents.

Gas-dynamic spraying of aluminum

A breakthrough in the field of metal repair and restoration has been the spraying technology. The gas dynamic spraying technology involves feeding finely dispersed aluminum particles (0.01-50 microns) through a supersonic (600-700 m/s) nozzle and heating compressed air to 400-600°C. As a result, an aluminum layer is formed on the metal surface that has high adhesion (40-100 N/mm2) and low porosity (1-3%).Coatings that are formed in the process of spraying have significant advantages:

  • when applying the coatings, the temperature of the substrate does not exceed 150 ° C;
  • coatings have high adhesion (40-100 N/mm2) and low porosity (1-3%);

  • it is possible to spray layers of almost any thickness;

  • light alloys can be sprayed: zinc, aluminum, silver.

Anodizing is an electrochemical process of creating a protective oxide film. This technology is used to treat not only aluminum, but also many non-ferrous metals. It is essentially the same as electroplating, only here the protective film is formed not by Zn or Cr, but by the metal being processed itself.

Anodizing is applied to products made of various metals, in particular Al, Mg, Ti, but in the first place is aluminum and alloys based on it.

The aluminum product and the lead cathode are placed in a bath with an aqueous sulfuric acid solution and an electric current of 50 to 100 V is applied. An oxide film is formed on the aluminum (anode), which can be given any color.

Anodizing is widely used for the treatment of castings made of light aluminum-based alloys, often binary, i.e. consisting of two components - Al-Mg, Al-Cu, but three-component - Al-Mg-Si and Al-Zn-Mg are also suitable.

Although with varying success, aluminum continues to assert its right to be used in the manufacture of car bodies. The bodies of the Audi A8 are made entirely of aluminum, and quite a few cars are equipped with aluminum exterior panels. Aluminum is good against atmospheric corrosion, but poorly painted. This problem is also solved by anodizing, which not only increases the adhesion to the paint coating, but also increases anti-corrosion properties.

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