CASTING SOURCE

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DIE CASTINGS

CAST - MACHINED - FINISHED

Die castings, pressure die castings, and vacuum die castings are processes by which foundries can rapidly create thin wall complex shapes, with high dimensional accuracy, and a very smooth attractive surface finish. The advantage to the die casting process is the ability to make large quantities of well defined castings quickly and cheaply that will require few secondary operations to obtain a finished part.

The disadvantage to the die casting process is that the initial die casting tooling cost is normally very expensive and the die casting process is limited to low temperature alloys, such as aluminum, brass, magnesiun, and zinc. Die castings are made by pouring, injecting, or pulling by vacuum melted alloys into the cavities of a hardened metal mold, called a die. Normally this is done in an automated die casting machine. Most dies have several cavities, making several parts with each casting cycle.

Die casting begins by making a steel die, which will be capable of making tens of thousands of castings. The dies are made in at least two sections. The die casting cycle begins by clamping the die sections together. Liquid alloy is then poured, injected, or pulled by vacuum into the die cavities. When it solidifies, the die opens and the castings are ejected. Once removed from the die, the die castings normally require a few secondary operations, usually just flash trimming, buffing, perhaps holes tapped or machined to a final tolerance and then anodized, panited, or plated.