Aluminum is easy to process, good visual effect, rich surface treatment means, aluminum surface treatment is mainly divided into: sandblasting, polishing, drawing, spraying, electroplating, spraying, coloring and so on
1. The sand blasting
The process of cleaning and coarsening metal surfaces using the impact of high-speed sand flow. This method of aluminum surface treatment can make the surface of the workpiece to obtain a certain cleanliness and different roughness, so that the mechanical properties of the workpiece surface is improved, so as to improve the fatigue resistance of the workpiece, increase the adhesion between it and the coating, prolong the durability of the coating film, but also conducive to the flow and decoration of the coating. This process is often seen in various Apple products and is increasingly being used in existing TV cases or middle frames.
2. The polishing
A process in which the surface roughness of the workpiece is reduced by mechanical, chemical or electrochemical methods in order to obtain a bright, flat surface. Polishing process is mainly divided into: mechanical polishing, chemical polishing, electrolytic polishing. Aluminum parts using mechanical polishing + electrolytic polishing can be close to the stainless steel mirror effect, giving a person with high-grade simple, fashionable feeling of the future (of course, easy to leave fingerprints but also more care).
3. The drawing
Metal wire drawing is a manufacturing process in which aluminum sheets are repeatedly sanded out of the wire. Drawing can be divided into straight line drawing, random drawing, spiral drawing, thread drawing. Metal wire drawing process, can clearly show each fine silk mark, so that the metal matte out of the fine hair luster, the product has fashion and sense of science and technology.
The external protection and decoration of equipment are usually carried out on the basis of oxidation. Aluminum parts should be pre-treated before painting in order to make the coating and the workpiece firmly combined, there are generally three methods: ①, phosphating (phosphate method) ②, chromatization (no chromium chromatization) ③, chemical oxidation
There are two main coloring processes for aluminum: one is aluminum oxidation coloring process, the other is aluminum electrophoresis coloring process. Various colors are formed on the oxide film to meet certain use requirements, such as black for optical instrument parts and golden gold for commemorative MEDALS.
6. Anodic oxidation
Anodic oxidation refers to the electrochemical oxidation of metal or alloy, aluminum and its alloy in the corresponding electrolyte and specific process conditions, due to the action of the impressed current, aluminum products (anode) on the formation of a layer of oxide film process. Anodic oxidation can not only solve the defects of aluminum surface hardness, wear resistance and other aspects, but also prolong the service life of aluminum and enhance the aesthetic degree, has become an indispensable part of aluminum surface treatment.
7, chemical polishing
Chemical polishing is a chemical processing method that uses the selective self-dissolution of aluminum and aluminum alloy in acidic or alkaline electrolyte solution to smooth and polish the surface of age, so as to reduce the surface roughness and PH. This polishing method has the advantages of simple equipment, no power supply, not limited by the size of the workpiece, high polishing speed and low processing cost. The purity of aluminum and aluminum alloy has a great influence on the quality of chemical polishing, the higher its purity, the better the polishing quality, and vice versa.
Passivation is a method to change the metal surface into a state that is not easy to be oxidized and slow down the corrosion rate of the metal.