öntforma

Öntforma is a Hungarian term referring to a mold or form used in casting processes to shape molten material into a predefined geometry. The mold provides a cavity that determines the external shape of the final part; after the molten material is poured or injected and solidifies, the part is removed from the mold.

In industrial use, öntforma encompasses a range of molding methods and materials. Metal casting commonly employs metal molds that can be reused many times (permanent molds), while other methods use expendable molds such as sand, plaster, or investment (lost-wax) molds. The choice of mold material and design depends on factors such as the material to be cast, required tolerances, surface finish, production volume, and cost. Core inserts may be used to create internal features, and gating systems and risers are incorporated to control flow and solidification.

Beyond metal casting, molds similar to öntforma are used in plastics and ceramics. Injection molding and die casting rely on multi-part molds that can form complex geometries with high precision. In these processes, considerations include mold cooling, venting, tool wear, and cycle times. Post-processing, such as removing parting lines, machining, or surface finishing, is often required to achieve final specifications.

The term originates from the Hungarian words for pouring (önt) and form/shape (forma). In English-language contexts, the concept is generally described as a casting mold or molding die. See also foundry, casting, die casting, injection molding.