What are the surface treatment methods of aluminum products

Aluminum products have the advantages of light weight, easy processing, and various surface treatment methods, which are used in many industries. So what are the surface treatment methods of aluminum products, and how to choose the surface treatment method is suitable for your own products? Below I list and summarize the commonly used surface treatment methods of aluminum products.

Pre-treatment method:

1. Grinding and polishing: Polishing refers to the use of mechanical, chemical or electrochemical action to reduce the surface roughness of the workpiece in order to obtain a bright and smooth surface processing method. Is the use of polishing tools and abrasive particles or other polishing media to modify the surface of the workpiece.

2. Sandblasting: The process of cleaning and coarsening the surface of the matrix by the impact of high-speed sand flow. The compressed air is used as the power to form a high-speed jet beam to spray the spray material (copper ore, quartz sand, emery, iron sand, Hainan sand) at high speed to the surface of the workpiece that needs to be treated, so that the appearance or shape of the outer surface of the workpiece surface changes, due to the impact of abrasive on the surface of the workpiece and cutting action, so that the surface of the workpiece to obtain a certain degree of cleanliness and different roughness, The mechanical properties of the workpiece surface are improved, so the fatigue resistance of the workpiece is improved, the adhesion between it and the coating is increased, the durability of the coating is extended, and the flow and decoration of the coating are also beneficial.

3. Wire drawing: Surface wire drawing treatment is a surface treatment method that forms lines on the surface of the workpiece by grinding the product to play a decorative effect. Because the surface drawing treatment can reflect the texture of metal materials, it has been loved by more and more users and more and more widely used. Wire drawing treatment can also be generally called sand sweeping, nylon sweeping, and so on. It is usually divided into straight silk and messy silk according to different surface effects. Straight silk is also called hair silk, messy silk is also called snow pattern, the good difference of silk type has a great subjectivity. Each user has different requirements for the surface grain and different preferences for the effect of the grain. Some people think hair is beautiful, some people like snow pattern, some people like long silk, some people like short silk. Due to the variety of wire effect, it is usually difficult to describe and specifically define, but by determining the processing method of wire drawing, the grinding product used, the process parameters and other ways to determine the effect of wire drawing wire.

4. Embossing: Embossing is a common processing technology for decorative packaging materials. The pressing pattern is divided into plate embossing and roller embossing. Embossing process is a kind of mold with concave and convex lines, under the action of a certain pressure and temperature, the pressure material (PVC, aluminum, wood, paper, etc.) is deformed, forming a certain pattern, so as to perform artistic processing on the surface of decorative packaging materials

Surface treatment:

1. anodic oxidation and hard oxidation: Anodic oxidation, electrochemical oxidation of metals or alloys. Aluminum and its alloy in the corresponding electrolyte and specific process conditions, due to the action of external current, the process of forming an oxide film on the aluminum product (anode). Anodizing, if not specified, usually refers to sulfuric acid anodizing.

In order to overcome the defects of surface hardness and wear resistance of aluminum products, expand the application range and extend the service life, surface treatment technology has become an indispensable part of the use of aluminum products, and anodizing technology is the most widely used and most successful.

Anodizing is to use metal or alloy parts as the anode, using the method of electrolysis to form an oxide film on its surface. The metal oxide film changes the surface state and performance, such as surface coloring, improving corrosion resistance, enhancing wear resistance and hardness, protecting the metal surface. The film thickness is generally 8um-10um. Can do a variety of colors, suitable for decorative pieces, outdoor use will be easy to fade.

Hard oxidation stands for hard anodizing treatment. Hard anodic oxide film generally requires a thickness of 25-150um, most of the hard anodic oxide film thickness of 50-80um, the film thickness is less than 25um hard anodic oxide film, used for parts such as tooth keys and spiral applications, wear-resistant or insulating anodic oxide film thickness of about 50um, in some special process conditions, It is required to produce a hard anodized film with a thickness of more than 125um, but it must be noted that the thicker the anodized film, the lower the microhardness of its outer layer can be, and the roughness of the film surface increases. Color is the color of electrolytic thickness of the material, according to the color of different materials into dark coffee, gray, brown, black, can not be dyed, can be used outdoors. Generally used as an environment without appearance requirements requiring wear resistance and salt spray resistance.

It is suitable for deformed aluminum products and may also be used for die-cast aluminum parts.

2. Fluorocarbon baking paint: Fluorocarbon baking paint is a super durable baking fluorocarbon paint, with fluorine resin as the main component, fluorocarbon baking paint is specially designed for spraying factory baking paint production line, with good durability, protection, lasting beauty and other excellent properties.

Fluorocarbon baking paint has super durability, super weather resistance, corrosion resistance, strong self-cleaning properties; Strong adhesion, high decoration, waterproof and anti-enzyme, acid and alkali resistance; Good film properties: quick drying, flexibility, scratch resistance, wash resistance; High transparency, high hardness, high fullness, no yellowing and other product features.

Fluorocarbon baking paint can be used for all kinds of aluminum curtain wall panels, aluminum profiles and other metal materials durable decorative protective coating, can also be used in steel structure equipment durable protective coating.

Fluorocarbon baking paint is flammable, should be stored in a cool place, avoid the sun and rain, away from heat sources, pay attention to fire prevention

3. Electrostatic powder spraying: electrostatic powder spraying is commonly known as "electrostatic spraying". Main features: The spraying method can be manual, automatic or manual + automatic. The spray material is 100% solid powder, the free powder can be recycled, and the paint recycling rate can reach 98%. Suspension transport system, high degree of automation. The coating has fewer micropores, good anti-corrosion performance, and can be sprayed with thick film at one time. As long as the powder coating is sprayed directly on the surface of the pre-treated MDF sheet, after baking, you can get a coating surface with excellent performance. General powder coatings have long-lasting coating properties, including friction resistance, impact resistance, cohesiveness, toughness, corrosion resistance and chemical resistance. The outdoor use of powder coatings, in addition to the above advantages, also includes high weather resistance and pollution resistance. Powder coating can be sprayed once to obtain a high thickness film, the film thickness can be between 50-300μm, and there is no droplet or accumulation phenomenon when solvent coating is thick.

4. Electrophoresis: Electrophoresis is also known as - electric (in), swimming paint, electrodeposition. Founded in the 1960s, it was first applied to automotive primers by Ford Motor Company. Because of its good anti-corrosion and anti-rust function, it is soon widely used in the military industry. In recent years, it has been applied to the surface treatment of daily hardware. Due to its excellent quality and high environmental protection, it is gradually replacing traditional paint spraying. Electrophoretic paint film: electrophoretic paint film has the advantages of full, uniform, flat and smooth coating, and the hardness, adhesion, corrosion resistance, impact performance and permeability of electrophoretic paint film are obviously superior to other coating processes. Features: (1) The use of water-soluble paint, water as the dissolving medium, saving a lot of organic solvents, greatly reducing air pollution and environmental hazards, while avoiding fire hazards; (2) The coating efficiency is high, the coating loss is small, and the utilization rate of the coating can reach 90% ~ 95%; (3) The coating film thickness is uniform, the adhesion is strong, the coating quality is good, all parts of the workpiece, such as the inner layer, depression, weld, etc., can obtain uniform and smooth paint film, which solves the painting problem of other coating methods on the complex shape workpiece; (4) High production efficiency, the construction can achieve automated continuous production, greatly improve labor efficiency; (5) The equipment is complex, the investment cost is high, the power consumption is large, the temperature of drying and curing requirements is high, the management of paint and coating is complex, the construction conditions are strict, and the wastewater treatment is required; (6) Only water-soluble paint can be used, and the color can not be changed during the painting process, and the stability of the paint is not easy to control if it is stored for too long. (7) Electrophoresis coating equipment is complex, high scientific and technological content, suitable for the production of fixed color.

5. Electroplating: Electroplating is the process of using the principle of electrolysis to plate a thin layer of other metals or alloys on some metal surfaces, which is the process of using electrolysis to attach a layer of metal film to the surface of metal or other materials to prevent metal oxidation (such as rust), improve wear resistance, electrical conductivity, reflective property, corrosion resistance (copper sulfate, etc.) and improve beauty. The outer layer of many coins is also plated.