There are many kinds of aluminum surface treatment method. At present, use high temperature wood grain transfer, the spray oxidation and coating. Alumina membrane layer can well protect the aluminum substrate from corrosion, aluminum profile which is the main reason for corrosion resistance.

Natural oxidation

Natural oxidation of aluminum profile is to react with oxygen in the air in the natural environment, formed in the surface of aluminum oxide layer, and makes the internal matrix continued to react with oxygen. Cover is transparent, the oxide film. Natural oxidation film, the color is not good, corrosion resistance is not strong, now rarely used.

Chemical oxidation

Chemical oxidation is to remove the surface of the aluminum alloy after degreasing, and remove ash content in the oxidation of oxidant and surfactant solution to form artificial oxide film. Surfactant plays a part in forming process to dissolve the role of the oxide film. Hole oxidation to continue and oxide film layer thickening.

Many different kinds of oxidation solution, usually using chromate as oxidant, carbonate as a surfactant. The advantage of chemical oxidation is easy to control and easy operation. Defect is high cost, environmental pollution, chemical oxidation of thin oxide film, production capacity is low.

Anodic oxidation

Anodic oxidation is aluminum in acidic electrolyte. Applying high voltage direct current (dc) so that the anion as anode, moved towards the anode, form a new oxygen alumina and anodic oxide film formed in the anode. Partly dissolved in the electrolyte, acid oxidation film to produce holes, thereby oxidation reaction can be conducted in depth. This approach allows the surface of aluminum porous structure formation, can undertake all kinds of color processing, and can be used as a base coat.

The advantage of anodic oxidation is thickness of oxide film, corrosion resistance, higher level and batch processing. At present, many aluminum alloy companies are keen to anodic oxidation and aluminum doors and Windows accessories company.