Casting

Metal casting is a manufacturing process in which molten metal is poured into a mold to create a desired shape once the metal solidifies. It's a versatile method used to produce complex metal parts of various sizes and shapes. 

Metal casting is used in various industries, including automotive, aerospace, machinery, and art. Different casting methods, such as sand casting, investment casting, die casting, and more, offer different levels of complexity, precision, and surface finish. The choice of casting method depends on factors such as the type of metal, desired part characteristics, and production volume. 

Pattern Creation: The process begins with the creation of a pattern, which is a replica of the final desired part. Patterns can be made from wood, plastic, or metal. The pattern is used to create a mold cavity into which the molten metal will be poured. 

Mold Making: The pattern is embedded in a molding material, which can be sand, plaster, ceramic, or other materials. This creates a mold that consists of two halves: the top half (cope) and the bottom half (drag). The mold cavity is the negative space of the pattern. 

Core Placement: In some cases, internal features of the part require a core, which is a removable shape that forms hollow areas or complex internal structures. Cores are placed in the mold to create these features.

Melting and Pouring: The chosen metal is melted in a furnace to its liquid state. Once molten, the metal is poured into the mold cavity through a pouring channel called a sprue. The metal fills the mold and takes the shape of the pattern.

Solidification: As the molten metal cools, it solidifies within the mold, conforming to the shape of the pattern and the mold cavity. The solidification process affects the material's microstructure and properties.

Cooling and Removal: After the metal has solidified and cooled sufficiently, the mold is opened, and the casting is removed. Excess material, known as the gating system (sprue, runner, and riser), is usually trimmed off.

Finishing: The casting may require additional finishing steps, such as grinding, machining, or surface treatment, to achieve the desired final appearance and dimensions.

Reuse: The pattern and mold can in some instances, be reused to create multiple castings. In some cases though, patterns can be damaged or wear out over time.

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