The fundamental process of metalcasting consists of five basic elements:

• Molding—The mold cavity must be formed from a material that will withstand the operating temperatures and conditions of the chosen casting process and metal.
• Pouring—The molten metal is poured into the mold and travels through its passages to fill the mold cavity.
• Solidification—During the solidification process, the metal cools and becomes a solid shape.
• Mold Removal—The cooled casting is removed from the mold.
• Secondary Operations—The casting is trimmed, cleaned, heat-treated, machined, inspected, painted, etc.

These five basic elements are supported by design and fabrication of the patterns and cores for the mold, the fabrication of the mold cavity and the melting of the metal.

A key part of designing a mold involves the use of cores. Cores are preformed masses of bonded sand or some other material that are used to make the internal passageways of a casting. Castings may require a single core, a complex assembly of cores or no cores at all. Like castings, cores are made in a mold, called a coldbox. Typically these cores are made of sand and may be combined with other materials that bind the sand together. Metal cores are used in permanent mold and diecasting processes. The type of cores used in each metalcasting process will also be part of your decision making process.

Molding processes can be broken into four general categories: sand casting processes; permanent mold processes; ceramic processes; and rapid prototyping. 

Sand Casting

Permanent Mold

Ceramic and Plaster Mold

Rapid Prototyping