Molded

Molded is the past participle of the verb mold, and it is used to describe objects or parts that have been shaped or formed by a mold. In manufacturing, a molded item is typically created by introducing or shaping material within a cavity that defines the final geometry, rather than by subtractive machining.

Molding processes encompass several methods. Injection molding injects molten material into a closed mold to create complex shapes with high dimensional accuracy. Compression molding presses material between heated molds, useful for thermosets and some fiber-reinforced composites. Blow molding forms hollow parts by inflating a heated polymer parison inside a mold, common for bottles. Rotational molding uses a heated mold that is rotated to distribute material, producing large hollow parts. Thermoforming heats a sheet and forms it over a model, often used for packaging. Casting, used for metals, ceramics, and some plastics, pours material into a mold where it solidifies. Finished molded parts may undergo trimming, finishing, painting, or coating, and require considerations of draft angles, shrinkage, cooling, and mold release to ensure quality and repeatability.

Materials commonly molded include plastics (such as polypropylene and ABS), metals (in die casting and some sand casting contexts), ceramics, and glass. Applications span consumer packaging, automotive components, housing and enclosures, toys, and household goods.

Note that British English often uses moulded instead of molded, and the term can also refer to a biological mold, which is a different concept despite the shared root.