Aluminium alloy casting process and equipment
The process of casting aluminium alloy is mainly divided into sand casting and die casting. The choice of casting process and equipment should be based on the requirements of mechanical properties, surface quality, dimensional accuracy and batch size. In general, appropriate mould materials and casting type should be selected according to actual production needs.
1. Sand casting
Sand casting is a casting process in which sand is used as the molding material. Sand casting has the advantages of wide application range, simple process, convenient equipment and low cost, and can be used to cast some large and medium-sized castings. The moulding material of sand casting is generally divided into green sand, self-hardening sand and furan resin sand. Green sand is widely used in production and is more suitable for large and medium-sized castings. Self-hardening sand has the properties of not easy to collapse, good heat resistance and strong adaptability to complex shaped castings. The Furan resin sand has both the characteristics of green sand and self-hardening sand, and has a high production speed and good surface finish.
2. Die casting
Die casting is a method of casting metal components by forcing melted metal alloy into a pre-made mould under high pressure. Die casting is suitable for mass production of complex and highly precise castings. Its main advantages are high production efficiency and good surface quality of castings. Die casting molding material is generally divided into cold hardening die casting and hot chamber die casting. The cold hardening die casting is suitable for casting complex and accurate structure of small products, especially for mass production. The hot chamber die casting is suitable for casting large and medium sized castings with good surface finish, but the cost is higher.
The choice of diecasting equipment should be based on the type and quantity of the castings. For the production of general small and medium-sized castings, high speed and low cost cold chamber die casting machine can meet the requirements; for the production of high precision and complex large and medium sized castings, the hot chamber die casting machine is the preferred choice.
3. Automatic Casting
Automatic casting is a method of casting which uses a machine instead of manual operation to realize the automated production process. Automatic casting is suitable for mass production of uniform and accurate parts, and its main advantages are fast production speed and high production efficiency. At present, the automatic casting machines used in the market include centrifugal casting machine, gravity casting machine, low pressure casting machine and vacuum casting machine. The centrifugal casting machine has the advantages of fast production speed and good surface finish of castings, and is suitable for mass production of disc type casting; the gravity casting machine is suitable for aluminum alloy castings with good surface finish, small size and complex shapes; the low pressure casting machine is suitable for the production of aluminum alloy castings with higher requirements for surface finish and mechanical properties; the vacuum casting machine has good surface finish and excellent porosity, impact and is suitable for the production of high-precision castings.
In summary, the selection of aluminium alloy casting process and equipment should be based on the requirements of mechanical properties, surface quality, dimensional accuracy and batch size of the castings. The production process should be reasonably planned and the equipment should be selected reasonably. Under the premise of meeting different production requirements, the equipment selection should be based on the production scale, output, precision and surface quality of the castings.
