A casting refers to a metal product obtained by pouring molten metal or alloy into a mold, cooling and solidifying it. During the use of castings, due to factors such as heating, expansion, and cooling of the metal, castings often suffer from external thermal shocks. Thermal shock can cause deformation, cracking, or fracture of castings, thereby reducing their service life and reliability. Therefore, improving the thermal shock resistance of castings is crucial for their application in engineering and manufacturing industries.

Casting coating is a chemical substance that can be applied to the surface of castings to improve their performance. By improving the composition and structure of casting coatings, the thermal shock resistance of castings can be improved. The following will introduce several common methods:

1. Adding flame retardants: Adding flame retardants to casting coatings can reduce their combustion performance and improve their fire resistance. Flame retardants can prevent the spread of flames and prevent the burning of castings. Common flame retardants include aluminum hydroxide, ammonium hexametaphosphate, etc.

2. Adding reinforcing agent: Adding an appropriate amount of reinforcing agent to the casting coating can increase the hardness and wear resistance of the coating, thereby improving the thermal shock resistance of the casting. Enhancers can be particles such as carbon fibers, ceramic microspheres, etc., or plasticizers such as polyurethane, silicone oil, etc. These enhancers can enhance the mechanical properties and thermal stability of coatings, and improve their thermal shock resistance.

3. Use ceramic coatings: Ceramic coatings have high thermal resistance and wear resistance, which can effectively resist the thermal shock of castings. Ceramic coatings can form a hard and wear-resistant protective layer on the surface of castings, blocking the conduction of heat, making the castings more resistant to high temperatures and thermal shocks.

4. Choose the appropriate coating thickness: Coating thickness is one of the important factors affecting the thermal shock resistance of castings. Properly increasing the thickness of the coating can improve the thermal isolation and thermal shock resistance of the casting. However, excessively thick coatings can increase thermal stress, which may lead to coating peeling, cracking, or deformation. Therefore, selecting an appropriate coating thickness is the key to improving the thermal shock resistance of castings.

5. Optimize coating structure: The structure of the coating can also affect the thermal shock resistance of the casting. Reasonably designing the structure of coatings, such as staggered layers and composite layers, can improve the wear resistance and thermal shock resistance of coatings. Meanwhile, optimizing the structure of the coating can also improve the adhesion and stability of the coating, preventing coating peeling and detachment.

6. Use special coatings: Some special coatings have high thermal shock resistance, which can improve the heat resistance of castings. For example, refractory coatings, temperature resistant coatings, etc. can form a high-temperature resistant protective layer on the surface of castings to prevent them from being subjected to thermal shock.

The above are some common methods to improve the thermal shock resistance of castings by improving casting coatings. However, it is necessary to choose appropriate improvement measures based on the specific application environment and casting materials. In addition, when using coatings to improve the performance of castings, attention should also be paid to factors such as the selection of coatings, construction methods, and compatibility between coatings and substrates. By comprehensively considering factors such as the composition, structure, and thickness of coatings, the thermal shock resistance of castings can be effectively improved and their service life can be extended

The above are some common methods to improve the thermal shock resistance of castings by improving casting coatings. However, it is necessary to choose appropriate improvement measures based on the specific application environment and casting materials. In addition, when using coatings to improve the performance of castings, attention should also be paid to factors such as the selection of coatings, construction methods, and compatibility between coatings and substrates. By comprehensively considering factors such as the composition, structure, and thickness of coatings, the thermal shock resistance of castings can be effectively improved, and their service life and reliability can be enhanced.