Seven Surface Treatment Methods for Aluminum Alloy

Method 1. Sandblasting treatment is mainly used for surface cleaning. Sandblasting (paint or plastic spraying) before painting can improve surface roughness and make a certain contribution to adhesion, but it is limited and not as good as chemical painting.

Method 2. Passivation treatment. Passivation is a method of transforming the metal surface into a non oxidizing one, which delays the corrosion rate of the metal.

Method 3.Coloring Treatment: There are two main processes for aluminum: one is the coloring process of aluminum oxidation, and the other is the coloring process of aluminum electrophoresis. Various colors are formed on the oxide film to meet certain usage requirements, such as optical instrument components typically used in black, commemorative chapters in gold, etc.

Method 4. Chemical Polishing Treatment: Chemical polishing is a selective self dissolution of acids or aluminum alloys in aluminum and aluminum alloys to reduce the surface roughness and pH of the surface.

This polishing method has the advantages of simple equipment, no power, no external size limitations, high inflow speed, and low processing cost. The purity of aluminum and aluminum alloys has a significant impact on the quality of chemical polishing. The higher the purity, the better the polishing quality.

Method 5.Chemical oxidation film treatment: Thin film, with a thickness of about 0.5-4 microns, porous, soft, and with good adsorption, can be used as the bottom layer of organic coatings. Chemical oxidation methods for aluminum and aluminum alloys can be divided into alkaline oxidation and acid oxidation methods based on their solution properties.

The properties of membranes can be divided into: oxide film, phosphate film, chromate film, and chromate phosphate film.

Method 6.Spray treatment: External protection, decoration, usually carried out on the basis of oxidation. Aluminum components should be pre treated before painting to ensure a firm combination of the coating and the workpiece, and there are three methods: phosphating (phosphate), chrome (chromium free chrome), and chemical oxidation.

Method 7.Electrochemical Oxidation Treatment: The chemical oxidation treatment equipment for aluminum and aluminum alloys is simple, with high operational efficiency, high production efficiency, wide application range, and limitations on parts and shapes. The thickness of the oxide film is about 5 to 20 microns (the thickness of the hard anodized oxide film can reach 60 to 200 microns), with high hardness, good heat resistance and insulation, chemical oxide resistance, porosity, and very good adsorption capacity.