The injection molding process for metals is very similar to that for plastics. A distinction is made in, hot chamber and cold chamber die casting. Both techniques use of a mold in which the material is injected under high pressure. After cooling of the material, the product is ejected from the mold, after which the mold closes and the cycle starts again.
The difference between the cold chamber and the hot chamber injection moulding originates from the way the material enters the injection chamber. For hot chamber injection molding, a large melting pot containing the injection portal has been added to the machine. Because in this case the material does not have to be removed from a central crucible, the process can be many times faster than cold chamber injection molding.
Because the injection system is constantly immersed in the liquid metal, it can quickly erode when processing metals with a high melting point. Therefore, this method is only suitable for low processing temperature metals such as zinc, lead and their alloys.
The pressure in the mold can be up to 30 MPa, which is lower than with a cold chamber production technique. The lifespan of the mold is around 250,000 pieces.