What are the common methods for surface treatment and coating of die casting products?

The surface treatment and coating of die-casting products are to improve the appearance quality of the product, protect the surface of the product, increase the additional functions of the product and prolong the service life of the product. The common surface treatment and coating methods of die casting products are as follows:

Sandblasting:
Sand blasting treatment is to spray sand particles at high speed, and remove impurities such as scale, residual sand cores and pores on the surface of the casting through impact and friction, so that the surface of the casting can meet the smoothness requirements. This method is suitable for situations that do not require a high surface finish of the product, such as body castings.

Polishing:
Polishing treatment is to mechanically polish and chemically dissolve the surface of the casting to achieve a certain degree of smoothness and brightness. This method is suitable for occasions that require high surface finish, such as jewelry, toys, etc.

Plating treatment:
The electroplating treatment is to put the casting into the electroplating tank containing metal ions, and the metal ions are reduced to metal elements by the action of electric current, and a metal protective layer is formed on the surface of the casting. Common electroplating methods include chrome plating, nickel plating, galvanizing, etc., which can improve the corrosion resistance and decoration of products.

Anti-oxidation treatment: Anti-oxidation treatment is to protect the surface from oxidation by coating the surface of the casting with a layer of non-oxidizable material to form an oxide layer. Common anti-oxidation methods include coating method, chemical treatment method, etc., which can improve the oxidation resistance of the product. Spray coating: Spray coating is to spray paint on the surface of castings to form a protective layer to protect and beautify. Coatings can be selected according to needs, such as epoxy resin coatings, polyurethane coatings, etc., which can improve the wear resistance, corrosion resistance and decorative properties of the product. Paint treatment: Baking paint treatment is to put the product in an oven for baking, so that the coating is cured to form a film, and the weather resistance and wear resistance of the product are improved. This method is suitable for occasions that require high product appearance and high protection performance. Carburizing treatment: Carburizing treatment is to immerse the casting in the medium containing carbon element, and make the surface of the casting rich in carbon element through the diffusion of carbon atoms under high temperature conditions, forming a layer of high carbide protective layer to improve the hardness and wear resistance of the product . Oxidation treatment: Oxidation treatment is to immerse the surface of the casting in a medium containing an oxidant, and make it oxidize under high temperature conditions to form an oxide film to increase the surface hardness and corrosion resistance of the product.
Electrophoretic coating:
Electrophoretic coating is a method of encapsulating charged paint particles on the surface of castings under the action of an electric field. The paint particles will automatically deposit on the surface of the casting under the action of the electric field force, and form a uniform and dense coating. Electrophoretic coating has the advantages of high efficiency, energy saving and environmental protection, and is suitable for castings of various shapes.
Thermal Spray:

Thermal spraying is the use of thermal energy to melt or heat metals, ceramics, plastics and other materials into powders, wires and other forms, and spray them on the surface of castings by spraying, blowing and other methods. Thermal spraying has excellent wear resistance, temperature resistance and corrosion resistance, and is widely used in pneumatic nozzles, anti-corrosion coatings and other fields.