In the design and manufacturing process of cylinder head molds, material selection plays a vital role, which is directly related to the overall performance of the mold, the effectiveness of the exhaust design, and the quality of the final casting. The exhaust design of the cylinder head mold is to ensure the smooth discharge of gas during the casting process, so as to effectively avoid the generation of defects such as bubbles and inclusions.

Thermal performance
The cylinder head is often in a high temperature environment during operation, so the thermal performance of the mold material is particularly critical. Properties such as thermal conductivity, thermal expansion coefficient and heat resistance have an important impact on the effectiveness of the exhaust design.
Thermal conductivity: High thermal conductivity materials can quickly conduct heat out of the mold, effectively reduce the temperature of the mold surface, and reduce the generation of thermal stress. This feature is particularly important in exhaust design, because under high temperature conditions, the expansion rate of the gas inside the mold increases significantly. If the heat cannot be dissipated in time, it may cause poor gas discharge, thereby affecting the quality of the casting.
Thermal expansion coefficient: The thermal expansion coefficient of the mold material directly affects its geometric stability. If the material expands too much at high temperature, it may cause the mold to deform, thereby affecting the size and shape of the exhaust channel, and thus affecting the flow capacity of the gas.
Heat resistance: The mold material needs to have excellent heat resistance to cope with the high temperature environment generated during the casting process. Materials with insufficient heat resistance may soften or deform at high temperatures, causing mold failure, thereby affecting the overall casting quality.

Mechanical properties
The mechanical properties of the mold also have a significant impact on its service life and the effectiveness of the exhaust design. Commonly used cylinder head mold materials include cast iron, aluminum alloy and steel.
Strength and hardness: The strength and hardness of the mold material directly affect its wear resistance and deformation resistance. During the high-pressure casting process, the mold needs to withstand the corresponding pressure and impact. Materials with insufficient strength may cause mold damage, which in turn affects the stability of the exhaust design.
Toughness: Good toughness helps to improve the mold's crack resistance under impact loads and reduce the risk of damage caused by material brittleness. During use, the mold may encounter thermal shock caused by temperature changes. Materials with insufficient toughness may cause the mold to crack, affecting the integrity of the exhaust channel.

Corrosion resistance
During the casting process, the mold comes into contact with molten metal and other chemicals, so the corrosion resistance of the material is particularly important.
Corrosive media: Some casting materials may react with gases or molten metals under high temperature conditions, causing corrosion on the mold surface, which in turn affects the shape and size of the exhaust channel. Selecting materials with strong corrosion resistance can effectively extend the service life of the mold and maintain the effectiveness of the exhaust design.
Surface treatment: In some cases, surface treatment of mold materials (such as coating, spraying, etc.) can enhance its corrosion resistance, thereby reducing the negative impact on the exhaust design. Through reasonable surface treatment technology, the corrosion resistance of the mold can be significantly improved, ensuring the stability and reliability of the mold in harsh environments.