Under fire exposure, what happens to the structural integrity of aluminum shells?

When aluminum shells are exposed to fire, their structural integrity may be weakened. Aluminum has a relatively low melting point compared to other metals, typically around 660°C (1,220°F). When subjected to high temperatures, the strength of aluminum diminishes significantly as it loses its rigidity and ductility. This can lead to deformation or failure of structural components made from aluminum, especially in critical applications where load-bearing is essential.

The other options imply that aluminum either remains unaffected, improves in durability, or becomes more resistant, which are not accurate in the context of fire exposure. Instead, the reality is that elevated temperatures compromise the material’s ability to withstand stress, making Option B the only accurate choice regarding the effects of fire exposure on aluminum shells.