What is Aluminum Extrusion Profile?
Aluminum extrusion profiles are aluminum alloys that are heated and melted, and then extruded into different sections. The main component is aluminum. The proportion of added aluminum is different, and the mechanical properties and application fields will also be different. The same goes for the finish of the aluminum extrusions. The three main surface treatments for aluminum extrusions are anodizing, electrophoresis and powder coating.
Why choose Aluminium Extrusion Profiles?
The density of aluminum extrusion profiles is about 2.7g/cm3, which is about steel, copper or brass, and the density is 7.83g/cm3 and 8.93g/cm3, respectively. Aluminum has good corrosion resistance in most applications, such as air, water, salt water, oil and other chemicals.
Aluminum extrusions are widely used due to their good electrical conductivity. The conductivity of aluminum is close to 1/2 of that of copper at the same weight.
The thermal conductivity of aluminum alloys is about 50-60% of that of copper, which is beneficial for the manufacture of heat exchangers, evaporators, heating appliances, cookers, automobile cylinder heads and radiators.
Aluminium extrusion profiles are non-magnetic and very important for the electrical industry and electronic parts manufacturing.
Aluminum extrusions are non-flammable, which is important for applications related to handling or contact with flammable and explosive materials.
The processing properties of aluminium extrusion profiles are very good. Many other wrought and cast aluminum alloys, and the state in which these alloys are produced, vary greatly in their machinability. Therefore, special machine tools or techniques are required.
The variation in the allowable deformation is controlled by the special properties of the aluminum extrusion profile, such as tensile strength, yield strength, ductility and related work hardening rates.
Aluminum is highly recyclable. The properties of recycled aluminium are almost identical to virgin aluminium.
What surface finish can we choose for aluminium extrusions?
1.Anodizing: Anodizing is a process in which aluminum is used as an anode and placed in an electrolyte, and a dense oxide film is formed on the surface of the aluminum extrusion profile through the action of the electrolyte.
2.Electrophoretic coating: Electrophoretic coating is the process of dissolving the electrophoretic coating material in water to electrolyze it to generate charged particles, and the charged particles move to the opposite pole under the action of external force and deposit on the aluminum extrusion profile. electric field, and a dense and uniform film appears.
3.Powder spraying: Electrostatic powder spraying is a process in which powder coatings are put into a spray gun, and under the action of compressed air, powder particles are adhered to the surface of aluminum extrusion profiles through high-voltage static electricity.
Why choose these three aluminum extrusion profile finishes?
- Anodizing: A porous oxide film will appear after anodizing, and the hardness can reach 500HV. The porous oxide film can adhere to lubricants and dyes, improving the corrosion resistance and wear resistance of the material surface. The oxide film has good insulation, and the breakdown voltage is higher than 30V/mm. The oxide film has strong high temperature resistance and can withstand high temperature of 1500 ℃. Aluminium can be anodised and dyed in many different decorative colours due to its excellent adhesion. Therefore, anodized aluminumis widely used in aerospace parts manufacturing, electronics, construction and architectural decoration of various aluminum extrusion profiles.
- Electrophoretic coating: Electrophoretic coating can reduce pollution to air and water, and since water is a dispersion medium, the amount of added solvent is also small, so there is no danger of fire. The coating material has a large throwing force and can cover the edges and gaps of aluminum extrusion profiles to form a dense and uniform oxide film. And the corrosion resistance of the whole part is also very good. The appearance quality of the electrophoresis part is high, the surface of the aluminum extrusion profile has no sagging, and there is no solvent condensation phenomenon. Electrophoretic coating adopts advanced RO recycling system, which can save chemical coatings and reduce environmental pollution. Since the recovery rate of paint is above 98%, the discharge of wastewater is also very small.
- Powder coating: Since the molecular weight of the powder sprayed resin is larger than that of the solvent-based coating, the surface of the aluminum extrusion profile is highly resistant to chemical media. It can greatly save working time and batches, and a coating of 50-300μm can be obtained in one powder spraying.Aluminum extrusion productsare strong and durable because powder spraying is free of the sag and pinhole defects that occur when applying solvent-based paints. Powder coating can enhance the aesthetics of aluminium extruded profiles as it is available in a wide range of colours. The aluminum-based surface quality and pretreatment quality are not as stringent as the other two methods.