ME or MEng Master of Engineering Structural Analysis and Materials Science 2

Question 1

Face-centered cubic (FCC) crystal structures are generally:

Accepted Answer

Ductile and have many slip systems

Answer

FCC metals (Al, Cu, Au, Ni) have 12 slip systems, enabling significant plastic deformation and high ductility.

Question 2

The stress intensity factor K_I in fracture mechanics represents:

Accepted Answer

Stress amplification at a crack tip under Mode I (opening) loading

Answer

K_I = σ√(πa)·Y quantifies the stress field magnitude at a Mode I crack tip; fracture occurs when K_I reaches the material's fracture toughness K_IC.

Question 3

Fatigue failure in metals typically initiates at:

Accepted Answer

Surface stress concentrations or defects

Answer

Fatigue cracks nucleate at surface irregularities, notches, or stress concentrators where cyclic stresses are locally amplified.

Question 4

In a simply supported beam with a central point load P and span L, the maximum bending moment is:

Accepted Answer

PL/4

Answer

For a simply supported beam with central load P, M_max = PL/4 at midspan, derived from the bending moment diagram.

Question 5

Which heat treatment process diffuses carbon into the surface of low-carbon steel to increase surface hardness?

Accepted Answer

Carburizing

Answer

Carburizing exposes low-carbon steel to a carbon-rich atmosphere at elevated temperature, enriching the surface layer with carbon for increased hardness.

ME or MEng Master of Engineering Practice Test

ME or MEng Master of Engineering Practice Test

ME or MEng Master of Engineering Structural Analysis and Materials Science 2