For casting, aluminium is not used in its pure form because then it would not satisfy most of the requirements and purposes. Only in combination with various alloy-elements like copper, nickel, manganese, silicon, with possible further additions of manganese or titanium, optimal qualities can be achieved.

Due to its low specific weight, aluminium casting is used in all cases where – as for instance in vehicle construction – the minimization of weight matters more than strength.

In the process of aluminium pressure casting liquid or viscous aluminium is pressed into a prefabricated steel mould. Because of the high costs of these moulds the procedure is, however, only used if a great number of items is required.

When the process of gravity die casting is carried out, the molten metal, under the impact of gravity, is cast into a mostly two-part permanent mould made of steel, whose inner surface forms the shape of the cast. Cavities and undercuts may be caused by cores of sand. After cooling down the mould is opened and the cast is taken out.

The procedure is a financially reasonable solution to the manufacture of medium-sized or large series of aluminium cast parts. With one die tooling up to 100,000 casts can be made.