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.

Classify imperfections in solids with one example each.

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

Explain the following: Space Lattice