Cee 3684 Test #1 Updated Questions And Correct Answers

CEE 3684 TEST #1 UPDATED QUESTIONS AND CORRECT
ANSWERS
Question:
1. Liquid water molecules are held together by secondary bonding forces created by the dipole nature
of the mole-cule(T/F)
Answer:
False

Question:
2. The bonding force between metal atoms are _________ bonds.
Answer:
Primary

Question:
3. The net Bonding energy de-creases to a minimum as the repulsion and attraction forces increase to
the equilibrium spacing between atoms(T/F)
Answer:
False

Question:
4. Increasing temperature of a crystalline material _______ spacing between atoms and ________
attractive bond forces between atoms.
Answer:
Increases, decreases

Question:
5. The unit cell which has the least dense packing of atoms is the ________.
Answer:
BCC

Question:
6. Imperfections in the crys-talline arrangement govern the mechanical response of metals
Answer:
True

Question:
7. The ductility of metals is creat-ed by ________ in the crystalline structure.
Answer:
Dislocations

Question:
8. All the energy is recovered during the unloading of a ________ material when loaded to below the
yield point.
Answer:
linear elastic

,Question:
9. Yielding of a metallic materi-al is caused by _______ stresses along the failure plane.
Answer:
Shear

Question:
10. Strain hardening of a steel ma-terial occurs because of ____. a.instability as interatomic spacing
increases b.yield at individual crystal boundaries c.
Answer:
Rearrangement in the interatomic spacing which decreases

Question:
11. Steel is an alloy of iron and carbon and other selection atoms(T/F)
Answer:
True

Question:
12. The ________ atom coexists within the spaces between the iron atoms.
Answer:
Carbon

Question:
13. The carbon content of struc-tural steels is typically less than ______ percent.
Answer:
2%

Question:
14. At the eutectoid point of .80% carbon, below 1340F, the structure of steel is ______.
Answer:
100% cementite

Question:
15. Below 1340F the structure of a .2% carbon steel is 25% pearlite and 75% ferrite(T/F)
Answer:
False

Question:
16. Pearlite is lamellae of ferrite and cementite which exhibits the mechanical properties of ferrite and
cementite.(T/F)
Answer:
True

Question:
17. ______ is in solid solution with iron, it increases strength and hardness but is not as effective as
carbon.
Answer:
Manganese

, Question:
18. phosphorous and sulfur con-tents of structural steels are limited because they form compounds
with iron and im-pair weldability(T/F)
Answer:
True

Question:
19. Annealing improves ductility and reduces internal stress-es.(T/F)
Answer:
True

Question:
20. A steel which exhibits ductile behavior in tension will also exhibit ductile behavior when exposed
to a biaxial stress con-dition.(T/F)
Answer:
False

Question:
21. When welding two pieces of steel together, structural changes take place within the heat affected
zone of the par-ent materials(T/F)
Answer:
True

Question:
22. Hydrogen induced within the steel atomic structure dur-ing welding can reduce the strength of the
steel and result in hydrogen-induced crack-ing(T/F)
Answer:
True

Question:
23. To maintain the reliability of the ductile behavior of struc-tural steels, the carbon con-tent and the
size of the fer-rite grains need to be con-trolled.(T/F)
Answer:
True

Question:
24. To _______ uniform corrosion you would _______ the steel.
Answer:
Reduce the rate of, apply cathode protection

Question:
25. The rate of uniform corrosion is predictable and a function of the atmospheric exposure
conditions.(T/F)
Answer:
True