In what class of material is stress whitening often seen, and what is the physical origin of the phenomenon?

What is the difference in appearance between ductile & brittle fractures?

Which is the correct definition of elastic deformation?       The behavior of a material when its size changes by the addition of heat.     The behavior describing a material's shape change under load that is self-reversing after the force is removed, so that the material returns to its original shape.       The behavior describing a material that deforms when subjected to stress and does not return to its original shape when the stress is removed resulting in permanent deformation.     Deformation caused by cleavage, where the material is actually pulled apart across atomic planes within the crystals or along the grain boundaries.

3. Linear elastic fracture mechanics (LEFM) predicts there will be an infinite stress at the tip of a crack. Why is this not the case? What happens microstructurally in metals, polymers and ceramics that prevents this?

How does the choice of material and cross-sectional geometry affect the bending behavior and structural integrity of a mechanical component?

Define the term“volumetric strain?

What is the failure due to fatigue? What factors influence the fatigue strength of the material? Under what loading types and materials would you use it?

Analyze the effects of thermal stress?

Under what circumstance could a fatigue crack become nonpropagating, even though the component experiences the same stress cyclic levels?

How to determine the yield point for materials that do not exhibit a well defined yield point? Name some of such materials