Design: There are two halves for the die casting machine- the fixed half and ejector. Both the haves are closed tightly by hydraulic pressure during the casting process. After the completion of the casting process the casts are removed through the ejector die half. The surface are of the cast is calculated by the die parting line which is the meeting point of the two parts of the mold.
Nowadays, special casting features like sprues, runners, gates, etc are also fixed to the mould. Before finalizing the design it is essential that the designers consult with the die caster, because that will help in understanding the requirements and the limitation of the die machine.
- Effective is casting complex components with dimensional accuracy
- The process is economical provided proper tooling and casting techniques are employed
- Minimal or no machining required
There are four types of dies:
- Single cavity to produce one component
- Multiple cavity to produce a number of identical parts
- Unit die to produce different parts at one time
- Combinations die to produce several different parts for an assembly
Cold Chamber Machines: Cold chamber machines are used for alloys such as aluminum and other alloys with high melting points. The molten metal is poured into a cold chamber, or cylindrical sleeve, manually by a hand ladle or by an automatic ladle. A hydraulically operated plunger seals the cold chamber port and forces metal into the locked die at high pressures.
High Integrity Die Casting Methods: There are several variations on the basic process that can be used to produce castings for specific applications. These include Squeeze casting, a method by which molten alloy is cast without turbulence and gas entrapment at high pressure to yield high quality, dense, heat treatable components.
Applications: Die castings provide integral fastening elements, such as bosses and studs. Holes can be cored and made to tap drill sizes, or external threads can be cast.
The die casting method is especially suited for applications where a large quantity of small to medium sized parts is needed with good detail, a fine surface quality and dimensional consistency.