Aluminum alloy and aluminum common surface treatment

Aluminum alloy and aluminum usually need to meet the demands of different surface treatment, common treatment over the surface of aluminum alloy electroplating, painting, drawing, anode, sandblast, passivation, polishing, oxidation film processing, etc.
1. Sandblasting, main effect is the surface cleaning, sand blast before coating (paint or coating) can increase the surface roughness, has certain contribution to improve adhesion, but the contribution is limited, as chemical processing before painting.

2. Color: there are two main types of coloring of aluminum process: one is aluminum oxidation coloring process, the other one is aluminum paint electrophoresis process. In the oxide film is formed on a variety of color, to meet certain requirements, such as optical instrument parts are commonly used in black, commemorative medallion is made with gold, etc.

3. Conductive oxide (chromate conversion coating) - for both protection and conductive occasions.

4. Chemical oxidation, with thin oxide film, thickness of about 0.5 ~ 4 microns, and porous, soft, has good adsorption, can be used as the bottom layer of organic coating, but its wear resistance and corrosion resistance than the anode oxidation membrane;

Aluminum pcb and aluminum alloy chemical oxidation process according to its nature of the solution can be divided into two types: alkaline oxidation and acid oxidation.
According to the layer properties can be divided into: oxide film, phosphate film, chromate film, chromic acid, phosphate film.

5. Electrochemical oxidation, chemical oxidation of aluminum and aluminum alloy processing equipment is simple, convenient operation, high efficiency, no electricity, the applicable scope is wide, without being limited by the size and shape of the parts. Oxide film thickness of about 5 ~ 20 microns (hard anodic oxidation film thickness up to 60 ~ 200 microns), has high hardness, good heat resistance and insulation, corrosion resistant ability higher than that of chemical oxidation film, porous, has good adsorption capacity.

6. Spraying: used for equipment of external protection, decoration, usually on the basis of the oxidation. Aluminum should carry on the pretreatment before coating to coating and artifacts in combination with strong, generally there are three measures.
1. Phosphate method (phosphate) 2.Chromium (without chrome) 3.Chemical oxidation.