Metal Casting Definition Types and Processes

Definition

Casting is a method where a solid material is dissolved, heated to suitable temperature (generally treated to change its chemical structure), and is then added into a mold or cavity, which keeps it in a proper form during solidification. As a result, in just one step, complex or simple designs can be created from any material that can be dissolved. The end product can have nearly any setting the designer needs.

For any casting procedure, choice of right alloy, sizing, shape, thickness, tolerance, structure, and weight, is really important.

Special needs such as, magnetism, deterioration, stress distribution also have an impact on the selection of metal casting process.

Opinions of the tooling manufacturer; foundry / machine house requirements, customer's exact product needs, and secondary procedures like paint work, must be addressed before choosing the right metal casting process.

Metal Casting Processes

There are numerous metal casting processes implemented in the manufacturing of parts. Two main divisions can be identified by the fundamental nature of a mold they use. There is expendable casting and long-lasting mold casting. Expendable molds are utilized for a single metal casting while long-lasting molds are utilized for several. When considering manufacturing procedures, there are pros and cons to both of the processes.

Expendable Mold

Can only make one metal casting

Made of sand, or other similar materials

Binders used to support material hold its shape

Mold that metal hardens in should be damaged to wipe out casting

More complex geometries are feasible for casting

Long-lasting Mold

Can create many metal castings

Generally made of metals or often a refractory ceramic

It has parts that can close or open, permitting eradication of the casting

Have to open mold limitations part designs

Types of Metal Casting

Centrifugal Casting

In this range of processes the melted material is required to disperse into the mold hole because of centrifugal speed. Centrifugal casting procedures can be categorized as true casting processes, which, when the melted material is added into the cavity, pushes it against the cavity walls where it stiffens into a hollow container; semi-centrifugal casting, varies from real centrifugal casting. In this process, the mold cavity is 100% filled with molten material so that the center, which is later on taken out, is exposed to low stress and is where inclusions and air is caught and the centrifuging approach in which melted material is poured into several mold cavities and which move around the core axis and shifted from the core axis and causes the cavities to be stuffed under excessive pressure.