What is the difference between extrusion and casting?

1. Definition and principle of extrusion
Squeezing is a processing method that forces metal materials through a mold to produce the desired cross-sectional shape. This is usually done at high temperatures to ensure that the metal can flow more easily and adapt to the shape of the mold. The extrusion process usually includes an extruder and a metal billet, which is placed in the extruder and then passed through the mold by applying pressure.
The principle of extrusion is based on the plasticity of materials at high temperatures. By applying sufficient pressure, the metal material can undergo deformation and gradually form the desired cross-section through the mold. This method can be used to produce metal products of various shapes, such as pipes, profiles, etc.
Extrusion is widely used in the manufacturing industry, especially in the production of aluminum profiles, copper pipes, and other aspects. Due to its ability to provide highly precise shapes and dimensions, extrusion has been widely used in industries such as construction and automotive manufacturing.
The advantages of extrusion include high production efficiency, precise size control, and increased material strength. However, the drawbacks of extrusion may include higher equipment costs and limitations applicable to certain specific shapes.
2. Definition and principles of casting
Casting is a processing method that involves injecting molten metal into a mold and then allowing it to cool and solidify to form the desired shape. Unlike extrusion, casting typically involves the process of transforming metals from liquid to solid. This can be achieved by heating the metal in a furnace and then pouring it into a mold.
The principle of casting is based on the melting and solidification points of metals. By melting the metal at an appropriate temperature and then injecting it into the mold, the metal gradually solidifies during the cooling process, ultimately forming the desired shape. Casting can be used to produce products of various sizes and shapes, from small parts to large castings.
Casting has a wide range of applications in the manufacturing industry, especially in fields such as automotive manufacturing and aerospace. By casting, components with complex geometric shapes can be produced, and compared to other processing methods, casting costs are lower.
The advantages of casting include being suitable for products of various sizes and shapes, and relatively low cost. However, the drawbacks of casting may include relatively low surface quality of the product, as well as the cost and time required for mold manufacturing and maintenance.
3. The difference between extrusion and casting
Squeezing is the process of forcing a metal billet through a mold to form a cross-sectional shape, while casting is the process of injecting molten metal into the mold and then cooling and solidifying to form the desired shape.
Squeezing is usually carried out at higher temperatures to increase the plasticity of the metal. On the contrary, casting involves melting the metal and then cooling and solidifying it at a lower temperature.
Extrusion is suitable for producing products with relatively simple cross-sections and longer lengths, such as profiles and pipes. Casting is suitable for producing complex shaped products, including large castings and components.
Squeezing usually provides a higher surface quality, while casting has a relatively lower surface quality and may require subsequent processing and treatment.