CWB Level 3 Module 20 Practice UPDATED
ACTUAL Exam Questions and CORRECT
Answers
Which of the following metals has the highest thermal conductivity? C
(a) carbon steel
(b) stainless steel (
(c) aluminum - CORRECT ANSWER - (c) aluminum
The Ellingham diagram C
(a) is a plot of thermal conductivity against temperature.
(b) shows the free energy of oxide formation against temperature.
(c) shows the rate of oxidation of metals against temperature. - CORRECT ANSWER - (b)
shows the free energy of oxide formation against temperature.
True or False?
A metal with a high negative free energy of oxide formation will generally require
greater shielding from the atmosphere during welding. - CORRECT ANSWER - True
Electricity can be conducted by:
(a) atoms and electrons.
(b) electrons and ions. C
(c) only ions. - CORRECT ANSWER - (b) electrons and ions. C
Which of the following elements is often present in submerged arc fluxes to improve arc
stability?
(a) copper (
(b) potassium (
, (c) nickel C
(d) tungsten - CORRECT ANSWER - (b) potassium (
Thoria is added to tungsten electrodes for what purpose? - CORRECT ANSWER - To
increase thermionic emission by lowering the work function.
True or False?
All pure metals have the same crystal structure. - CORRECT ANSWER - False. Metals
generally have one of three basic structures.
Which crystal structure(s) is (are) composed of close-packed planes? - CORRECT
ANSWER - FCC and HCP
The real strength of metals is lower than the theoretical value because:
(a) real crystals always fracture along specific crystal planes.
(b) grain boundary sliding occurs.
(c) the presence of dislocations facilitates slip. - CORRECT ANSWER - (c) the presence
of dislocations facilitates slip.
Multiplication and subsequent congestion of moving dislocations causes:
(a) elastic extension.
(b) work or strain hardening.
(c) a drop in the yield stress. - CORRECT ANSWER - (b) work or strain hardening.
Which of the following elements are most likely to form interstitial solid solutions?
(a) copper
(b) nickel
(c) carbon - CORRECT ANSWER - (c) carbon
ACTUAL Exam Questions and CORRECT
Answers
Which of the following metals has the highest thermal conductivity? C
(a) carbon steel
(b) stainless steel (
(c) aluminum - CORRECT ANSWER - (c) aluminum
The Ellingham diagram C
(a) is a plot of thermal conductivity against temperature.
(b) shows the free energy of oxide formation against temperature.
(c) shows the rate of oxidation of metals against temperature. - CORRECT ANSWER - (b)
shows the free energy of oxide formation against temperature.
True or False?
A metal with a high negative free energy of oxide formation will generally require
greater shielding from the atmosphere during welding. - CORRECT ANSWER - True
Electricity can be conducted by:
(a) atoms and electrons.
(b) electrons and ions. C
(c) only ions. - CORRECT ANSWER - (b) electrons and ions. C
Which of the following elements is often present in submerged arc fluxes to improve arc
stability?
(a) copper (
(b) potassium (
, (c) nickel C
(d) tungsten - CORRECT ANSWER - (b) potassium (
Thoria is added to tungsten electrodes for what purpose? - CORRECT ANSWER - To
increase thermionic emission by lowering the work function.
True or False?
All pure metals have the same crystal structure. - CORRECT ANSWER - False. Metals
generally have one of three basic structures.
Which crystal structure(s) is (are) composed of close-packed planes? - CORRECT
ANSWER - FCC and HCP
The real strength of metals is lower than the theoretical value because:
(a) real crystals always fracture along specific crystal planes.
(b) grain boundary sliding occurs.
(c) the presence of dislocations facilitates slip. - CORRECT ANSWER - (c) the presence
of dislocations facilitates slip.
Multiplication and subsequent congestion of moving dislocations causes:
(a) elastic extension.
(b) work or strain hardening.
(c) a drop in the yield stress. - CORRECT ANSWER - (b) work or strain hardening.
Which of the following elements are most likely to form interstitial solid solutions?
(a) copper
(b) nickel
(c) carbon - CORRECT ANSWER - (c) carbon
