Aluminum and aluminum alloys have the characteristics of easy processing, rich surface treatment methods, and good visual effects, and are now widely used in a wide range of applications. Usually, after the rough machining of parts is completed, multiple surface treatments will be carried out according to the surface requirements. For aluminum and aluminum alloys, what are the main surface treatments? Let us take you through!
Oxidation
Aluminum itself has a layer of aluminum oxide film, which has a certain corrosion resistance. But this layer of aluminum oxide film will make the surface of the aluminum profile lose its original luster, and all aluminum alloy products generally require special oxidation treatment for oxidation coloring. Let it have corrosion resistance, wear resistance and other functions.
The oxidation process is: degreasing (oil removal), alkali etching, anodizing, activation, dyeing, sealing
Secondary oxidation
Some characters on the surface of some electronic products are raised gloss effect, which can be obtained by secondary oxidation and stamping.
Surface drawing
According to the surface requirements of aluminum alloy, several drawing effects such as straight grain, chaotic grain, thread, corrugation, and spiral grain can be produced.
Sandblasting
In order to meet the requirements of soft luster, etc., sandblasting can be used to obtain the surface effect of film light or reflective surface. Surface blasting can overcome the common defects of most aluminum surfaces. But the main function is to clean the surface. Sandblasting (paint or plastic spraying) before painting can improve the surface roughness, which has a certain contribution to the adhesion but is limited, which is not as good as chemical painting.
High light
The high-gloss treatment is generally carried out on flat aluminum parts, and the effect of milling machine processing is performed on the edge of the aluminum part and other places that need to be conspicuously treated.
Spraying
There are two ways of spraying: baking varnish and powder spraying.
Scrub
Frosting can make the bright aluminum alloy avoid the shortcoming of light interference under certain environment and conditions. Its surface is as delicate and soft as brocade, which is very popular in the market. However, the existing frosted materials must overcome the uneven surface grains. , and can see the lack of pattern.
Passivation
Passivation treatment, passivation is the method of turning the metal surface into a non-oxidizing method, delaying the corrosion rate of the metal.
Chemical polishing treatment
Chemical polishing is the selective self-dissolution of acid or aluminum alloy in aluminum and aluminum alloy to reduce the age of the surface to reduce its surface roughness and pH chemical processing method. This polishing method has the advantages of simple equipment, no power, not limited by external dimensions, high inflow speed and low processing cost. The purity of aluminum and aluminum alloys has a great influence on the quality of chemical polishing, the higher the purity, the better the polishing quality, the better.
Chemical oxide film treatment
A thin film will be formed on the surface of aluminum parts with a thickness of about 0.5-4 microns. It is porous, soft, and has good adsorption. It can be used as the bottom layer of organic coatings. The method of chemical oxidation of aluminum and aluminum alloys can be determined according to its solution properties. Divided into alkaline oxidation and acid oxidation methods.
The nature of the film can be divided into: oxide film, phosphate film, chromate film, chromic acid-phosphoric acid film.
Hope the above content can help you.
