Which of the following metals is more commonly cast in a crucible furnace?

Copper is more commonly cast in a crucible furnace due to its specific casting requirements and the characteristics of the metal. Crucible furnaces allow for controlled melting of metals that require precise temperature management, which is crucial for copper. This metal has a relatively high melting point (around 1,984°F or 1,085°C) and benefits from the efficient thermal properties of crucible furnaces, which can melt small to medium quantities of material without the large scale typically involved in other furnace types.

Furthermore, the use of crucible furnaces allows for the melting of high-purity copper, which is essential for many electrical and mechanical applications where conductive and ductile properties are critical. The ability to melt and hold copper in small batches also supports the production of intricate shapes and varying alloy compositions, which are often required in specialized applications.

In contrast, while iron, steel, and aluminum can also be cast, they typically utilize other forms of furnaces that are better suited for their melting and casting processes, such as cupola furnaces for iron or larger induction furnaces for aluminum and steel.