Which properties are common to body-centered cubic (BCC) metals?

• A. High strength and low ductility.
• B. High ductility.
• C. Low strength.
• D. Non-conductive.

Answer: (A)

BCC metals tend to be strong yet not very ductile at room temperature because their crystal structure makes dislocation motion more restricted. The body-centered cubic arrangement hinders the easy glide of dislocations, so the material resists plastic deformation, giving high strength. But that same restriction reduces ductility, so the metal doesn’t deform plastically as readily and tends to fracture or yield less before breaking. As temperature rises, dislocations move more easily and ductility improves, though strength can shift with temperature. Metals conduct electricity, so non-conductive is not a property of BCC metals. Low strength would not describe these materials, and high ductility is not typical at room temperature. Thus, high strength with relatively low ductility best describes common BCC metals.