CWB Welding
Inspector Level III
Study Guide (solved &
updated)
Which of the following metals has the highest thermal conductivity?
(a) carbon steel
(b) stainless steel
(c) aluminum - answer (c)
The Ellingham diagram
(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. - answer
(b)
True or False?
A metal with a high negative free energy of oxide formation will generally
require greater shielding from the atmosphere during welding. - answer
True
Electricity can be conducted by:
(a) atoms and electrons.
(b) electrons and ions.
(c) only ions. - answer (b)
, Which of the following elements is often present in submerged arc fluxes
to improve arc stability?
(a) copper
(b) potassium
(c) nickel
(d) tungsten - answer (b)
Thoria is added to tunsten electrodes for what purpose? - answer To
increase thermionic emission by lowering the work function.
True or False?
All pure metals have the same crystal structure. - answer False. Metals
generally have one of three basic structures.
Which crystal structure(s) is (are) composed of close-packed planes? -
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. - answer (c)
Multiplication and subsequent congestion of moving dislocations causes:
(a) elastic extension.
(b) work or strain hardening.
(c) a drop in the yield stress. - answer (b)
Which of the following elements are most likely to form interstitial solid
solutions?
(a) copper
(b) nickel
Inspector Level III
Study Guide (solved &
updated)
Which of the following metals has the highest thermal conductivity?
(a) carbon steel
(b) stainless steel
(c) aluminum - answer (c)
The Ellingham diagram
(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. - answer
(b)
True or False?
A metal with a high negative free energy of oxide formation will generally
require greater shielding from the atmosphere during welding. - answer
True
Electricity can be conducted by:
(a) atoms and electrons.
(b) electrons and ions.
(c) only ions. - answer (b)
, Which of the following elements is often present in submerged arc fluxes
to improve arc stability?
(a) copper
(b) potassium
(c) nickel
(d) tungsten - answer (b)
Thoria is added to tunsten electrodes for what purpose? - answer To
increase thermionic emission by lowering the work function.
True or False?
All pure metals have the same crystal structure. - answer False. Metals
generally have one of three basic structures.
Which crystal structure(s) is (are) composed of close-packed planes? -
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. - answer (c)
Multiplication and subsequent congestion of moving dislocations causes:
(a) elastic extension.
(b) work or strain hardening.
(c) a drop in the yield stress. - answer (b)
Which of the following elements are most likely to form interstitial solid
solutions?
(a) copper
(b) nickel
