Die casting is an efficient metal casting manufacturing process, commonly used in the manufacturing industry. The molten metal of liquid and semi-liquid is forced into a pre-shaped mold(dies) with very high speed and pressure, then the molten metal has cooled and hardened. At last, it is removed from the mold(dies) to manufacture high precision die-cast products. Molds(dies) are designed to cast engineered shapes and complex features with great accuracy and consistent replication. It’s a process similar to the plastic injection process. There are two different methods of die casting processes: hot chamber die casting and cold chamber die casting. In other words, we need a hot chamber die-casting machine and cold chamber die-casting machine.
Hot chamber die casting
Hot chamber die casting always uses a hot chamber die casting machine. It is also known as a gooseneck die casting machine. The machine has an alloy melting pot as a part of the machine itself, where the metal is heated to a molten state in a die-casting machine, rather than in a separate machine or furnace. The molten metal liquid and semi-liquid were in the die casting machines, and they were forced into the pre-shaped molds(dies), through a high-pressure hydraulic plunger.
We can found the one standard production cycle is rather fast which is around 15-20min only. And the process of metal melting is very easy and simple. So hot chamber die casting is suit for automation production.
But the machine can not produce metals with high melting points such as aluminum, which will carry the iron out of the melting pot. As a result, hot chamber die casting machines are commonly used for alloys of Zinc, magnesium, tin, and Lead.
And the hot chamber die casting is suit the small die casting parts, but not used for the large casting parts.
Cold chamber die casting
Cold chamber die casting uses the cold chamber die casting machine, which with a separated furnace outside, where the metal will be heated to a molten state. Then the metal liquid will be poured into a machine with a ladle, they will be forced into the pre-shaped mold through high-pressure hydraulic plunger. The pressure requirements for cold chamber casting are typically higher than those of hot chamber dice casting. It is similar to the hot chamber machine. But the difference is the cold chamber die casting machine don’t have gooseneck.
It is obvious, one standard production cycle is longer and the material wastage is larger than hot chamber die casting, due to the metal liquid and semi-liquid need to be poured into the cold chamber.
Cold chamber die-casting machines can be used for die casting production when metals cannot be produced by hot chamber die-casting machine. Metals including aluminum, brass, and copper.