Pros and Cons of Cold Casting
The process of die casting aluminum using the cold casting method is similar to the hot casting process, but has one major difference. Rather than the metal melting in the same machine as the mold itself, the melted metal is melted in a different machine, then transferred to the die casting chamber via a cold chamber. There are both advantages and disadvantages to the cold casting process for die casting aluminum, but cold casting is usually used with aluminum due to the high melting point of the metal.
Pros: In the cold casting process, the metal is pushed into the die with a plunger that forces the metal into to mold with high pressure. This ensures that the metal reaches all parts of the mold for a precise fit every time. Higher temperature melting metals, such as zinc, magnesium, and aluminum have such a high melting point that they require the use of a separate, hotter unit to melt the metal and prepare it for the mold. The dies made from cold casting are denser than dies made from the hot casting process, because of the high pressure used to create the die.
Cons: Cold casting is not all advantageous to the manufacturer, however. Using multiple machines make the production process take much longer, which prevents the factory from creating as many products in one day. Quality control is a huge issue as well. If the factory does not have proper quality control, the metal can easily become oxidized or have other quality problems during the transfer between machines.
In general, the cold casting process has many advantages over hot casting if the factory can maintain a high level of quality control. Cold casting also works much better with aluminum, and will provide consistent results every time.