Engineering Materials

Choose the correct option:

Which crystal structure has the highest packing factor and 12 slip systems, making metals with this structure highly ductile?

(i) Body-centered cubic (BCC)
(ii) Face-centered cubic (FCC)
(iii) Hexagonal close-packed (HCP)
(iv) Simple cubic

Choose the correct option:

The critical resolved shear stress (CRSS) is defined as:

(i) The tensile stress required for dislocation motion
(ii) The shear stress resolved on the most favorable slip system required to initiate slip
(iii) The maximum shear stress in a crystal regardless of orientation
(iv) The stress needed to create new dislocations

Choose the correct option:

A family of directions is represented by

(i) (hkl)
(ii) {hkl}
(iii) <uvw>
(iv) [uvw]

Describe the three main types of metallic crystal structures (BCC, FCC, HCP) with their coordination numbers and packing factors.

Deduce the packing fraction of BCC and FCC crystal structure with a neat sketch.

Classify imperfections in solids with one example each.

Explain the following: Space Lattice