What is the primary method for shaping metals in a liquid state?

The primary method for shaping metals in a liquid state is casting. In the casting process, molten metal is poured into a mold where it solidifies into the desired shape. This method is particularly useful for creating complex geometries and large components that would be difficult or impossible to achieve with solid-state processing techniques.

Casting allows for a high degree of flexibility in design and can accommodate a wide variety of metal alloys. Once the metal cools and solidifies in the mold, it takes on the precise form of the cavity, making it an efficient way to produce parts with specific dimensions and features.

Other methods such as forging, molding, and extrusion involve shaping the metal primarily in its solid state or require pre-processing steps where the material is not liquid. Forging, for example, is a process that involves shaping metal using compressive forces without it being molten, while molding generally pertains to shaping materials such as plastics. Extrusion involves forcing metal through a die to create a specific cross-section, but again, this occurs when the metal is solid or semi-solid, not in a fully molten state as in casting.