Through chemical or electrochemical methods, a layer of oxide film is formed on the metal surface. For steel materials, the most common treatment is blackening. For aluminum and aluminum alloys, anodizing is often used. The product is energized in a specific electrolyte to form a hard, wear-resistant and corrosion-resistant aluminum oxide film on its surface.

The blackening treatment of steel is often used for mechanical parts, knives, etc., which not only increases corrosion resistance but also has a certain decorative effect. The anodizing of aluminum and aluminum alloys is widely used in the construction, electronics, automobile and other industries. It has beautiful appearance and good weather resistance and wear resistance.

A spray gun or other spraying equipment uses compressed air or mechanical power to disperse liquid paint into tiny droplets, making the paint form a mist that flies to the metal surface driven by the air flow, and forms a continuous paint film after drying and curing.

In the furniture, home appliances, automobile and other industries, spray painting is widely used to give products an aesthetic appearance. It can prevent metals from being corroded, worn and eroded by chemicals in the external environment.

The powder coating is adsorbed onto the metal surface by static electricity, after the workpiece is sent into an oven for high-temperature baking, generally at a temperature of about 180-220°C. As the temperature decreases, it gradually solidifies to form a uniform and dense coating.

It is widely used in surface decoration and protection of various metal products, such as furniture, automobiles, mechanical shells, etc. Powder spraying can provide rich colors and textures, with good weather resistance and corrosion resistance. At the same time, it has certain heat insulation and insulation properties.

Polishing is a process used to improve the surface finish and glossiness of metals. Polishing tools and polishing agents are used to finely grind the metal surface to remove surface blemishes, scratches, oxide layers, etc.

Polishing can remove microscopic defects on the metal surface, making the surface of the object as smooth as a mirror, enhancing the wear resistance and fatigue resistance. It is widely used in jewelry, decorations, electronic products and other fields.

The ink is squeezed by a scraper and transferred to the substrate through the mesh of the screen printing plate，forming a printed product consistent with the image and text of the printing plate.

Some parts after silk screen printing play the role of anti-corrosion or insulation, and can also increase the beauty and recognition of the product. This process is often used for electrical housings, electronic components, and mechanical parts.

Laser engraving is based on the principle of the photothermal effect of lasers. After the laser beam is focused, the energy is highly concentrated in a very small area, causing the surface of the irradiated material to instantly absorb a large amount of laser energy, causing the temperature to rise sharply, thus causing physical or chemical changes in the material.

It can be used to permanently mark brand names, perform high-precision engraving of parts in the fields of electronics, aerospace, etc. Meanwhile, it can also improve the hardness and wear resistance of the surface of parts.

A method of depositing a layer of metal or alloy on a metal surface using electrolysis principles.

It can improve the corrosion resistance, wear resistance, decorativeness and conductivity of metals, etc. It is widely used in automobile, electronics, hardware and other industries, such as chrome-plated decorative strips of automobiles, tin-plated pins of electronic products, etc.