CWB WELDING INSPECTOR
LEVEL III STUDY GUIDE WITH
ACTUAL EXAM QUESTIONS AND
DETAILED VERIFIED ANSWERS
ALREADY GRADED A+ LATEST
AND COMPLETE VERSION
"Which of the following metals has the highest work hardening coefficient?
(a) 70/30 brass
(b) aluminum
(c) copper
(d) low carbon steel - CORRECT ANSWER=> (a)"
"True or False?
Recrystallization always involves the formation of a new phase. - CORRECT ANSWER=> False"
"To get recovery and recrystallization the metal must have been previously
(a) quenched.
(b) heated.
(c) cold worked. - CORRECT ANSWER=> (c)"
"Can strain aging in low carbon steels take place at room temperature? - CORRECT ANSWER=>
Yes"
"Why is the temperature range 150°C-400°C usually avoided when forming steels? - CORRECT
ANSWER=> Because of "blue brittleness", i.e., lower ductility due to dynamic strain aging."
1|Page
,"Which of the following is a condition for an alloy to show precipitation hardening?
(a) there must be a eutectoid system
(b) the solubility of one component must rise with increasing temperature
(c) there must be complete solid solubility - CORRECT ANSWER=> (b)"
"How does yield strength vary with grain size? - CORRECT ANSWER=> Inversely as the square root
of the grain size."
"Which of the following factors increases the degree of constitutional supercooling?
(a) very slow solidification rate
(b) an alloy with a very narrow solidification range
(c) an alloy with a wide solidification range - CORRECT ANSWER=> (c)"
"Hot Cracking during welding is more likely in:
(a) pure metals.
(b) alloys with a wide solidification range.
(c) alloys with a very high alloy content. - CORRECT ANSWER=> (b)"
"Which of the following alloys would you expect to give the highest risk of hot cracking?
(a) Al-0.1%Cu
(b) Al-3%Cu
(c) Al-8%Cu - CORRECT ANSWER=> (b)"
"If centerline solidification cracking is occuring in welding a structural steel what is a likely
cause?
(a) electrical extension too long
(b) arc voltage too high
(c) welding current and speed too high
(d) weld too large - CORRECT ANSWER=> (c)"
"What is the most likely cause of porosity in aluminum welds?
(a) hydrogen
(b) nitrogen
(c) argon
(d) oxygen - CORRECT ANSWER=> (a)"
"How can porosity due to nitrogen be controlled in welding nickel? - CORRECT ANSWER=> By
using filler metal containing titanium."
2|Page
,"What is the most likely cause of porosity in carbon steel welds?
(a) hydrogen from reduction of water
(b) nitrogen
(c) carbon monoxide from reaction of oxygen with carbon
(d) oxygen direct from the air - CORRECT ANSWER=> (c)"
"What elements are included in electrodes or fluxes to control porosity in steel welds?
(a) silicon, aluminum, manganese
(b) copper, nickel, molybdenum
(c) sulphur, phosphorus, selenium
(d) silica, alumina, magnesia - CORRECT ANSWER=> (a)"
"What is thermal conductivity divided by specific heat and specific gravity known as? - CORRECT
ANSWER=> Thermal diffusivity"
"True or False?
A metal with a low thermal conductivity is more likely to reach the maximum melting efficiency
when welded. - CORRECT ANSWER=> True"
"Would a joint geometry designed for thick stainless steel be perfectly acceptable for welding
thick aluminum? - CORRECT ANSWER=> No. Grooves for thick aluminum would have a wider
angle than for stainless steel."
"When welding on a thick plate the cooling rate is proportional to the:
(a) heat input.
(b) inverse of the heat input.
(c) inverse of the square of the heat input. - CORRECT ANSWER=> (b)"
"From Figure 11.10(Module 20-2014, page 54), estimate the cooling rate for a submerged arc
bead on a 19 mm plate (no preheat) with an energy input of 1.77 kJ/in. - CORRECT ANSWER=>
16°C/s at 540°C"
"Which of the following metals is likely to need the greatest degree of shielding from the
atmosphere during welding?
(a) copper
(b) lead
(c) titanium
3|Page
, (d) steel
(e) gold - CORRECT ANSWER=> (c)"
"In an electroslag flux the current is carried mainly by:
(a) neutral oxides.
(b) holes.
(c) mobile ions.
(d) thermionic electrons.
(e) free electrons. - CORRECT ANSWER=> (c)"
"Compared with pure tungsten, a thoriated tungsten electrode is expected to:
(a) get hotter more quickly.
(b) absorb more electrons.
(c) have a shorten life.
(d) operate at a lower temperature for the same current.
(e) emit more ions. - CORRECT ANSWER=> (d)"
"The presence of close-packed planes in FCC metals gives many of them the special property of:
(a) good high-temperature strength.
(b) the ability to undergo extensive plastic deformation.
(c) brittleness at low temperatures.
(d) complete solubility with all other metals.
(e) small grains. - CORRECT ANSWER=> (b)"
"Work hardening occurs because of:
(a) fine precipitates.
(b) a reduction in the number of dislocations making slip more difficult.
(c) locking of dislocations by carbon and nitrogen atoms.
(d) multiplication and congestion of dislocations. - CORRECT ANSWER=> (e)"
"Nickel and copper have complete solid solubility. Copper has a lower melting point then nickel.
If a 50/50 Cu-Ni alloy is cooled from the liquid what will be the composition of the first solid to
form?
(a) 50% Cu
(b) less than 50% Cu
(c) Pure Cu
(d) Pure Ni
(e) more than 50% Cu - CORRECT ANSWER=> (b)"
4|Page
LEVEL III STUDY GUIDE WITH
ACTUAL EXAM QUESTIONS AND
DETAILED VERIFIED ANSWERS
ALREADY GRADED A+ LATEST
AND COMPLETE VERSION
"Which of the following metals has the highest work hardening coefficient?
(a) 70/30 brass
(b) aluminum
(c) copper
(d) low carbon steel - CORRECT ANSWER=> (a)"
"True or False?
Recrystallization always involves the formation of a new phase. - CORRECT ANSWER=> False"
"To get recovery and recrystallization the metal must have been previously
(a) quenched.
(b) heated.
(c) cold worked. - CORRECT ANSWER=> (c)"
"Can strain aging in low carbon steels take place at room temperature? - CORRECT ANSWER=>
Yes"
"Why is the temperature range 150°C-400°C usually avoided when forming steels? - CORRECT
ANSWER=> Because of "blue brittleness", i.e., lower ductility due to dynamic strain aging."
1|Page
,"Which of the following is a condition for an alloy to show precipitation hardening?
(a) there must be a eutectoid system
(b) the solubility of one component must rise with increasing temperature
(c) there must be complete solid solubility - CORRECT ANSWER=> (b)"
"How does yield strength vary with grain size? - CORRECT ANSWER=> Inversely as the square root
of the grain size."
"Which of the following factors increases the degree of constitutional supercooling?
(a) very slow solidification rate
(b) an alloy with a very narrow solidification range
(c) an alloy with a wide solidification range - CORRECT ANSWER=> (c)"
"Hot Cracking during welding is more likely in:
(a) pure metals.
(b) alloys with a wide solidification range.
(c) alloys with a very high alloy content. - CORRECT ANSWER=> (b)"
"Which of the following alloys would you expect to give the highest risk of hot cracking?
(a) Al-0.1%Cu
(b) Al-3%Cu
(c) Al-8%Cu - CORRECT ANSWER=> (b)"
"If centerline solidification cracking is occuring in welding a structural steel what is a likely
cause?
(a) electrical extension too long
(b) arc voltage too high
(c) welding current and speed too high
(d) weld too large - CORRECT ANSWER=> (c)"
"What is the most likely cause of porosity in aluminum welds?
(a) hydrogen
(b) nitrogen
(c) argon
(d) oxygen - CORRECT ANSWER=> (a)"
"How can porosity due to nitrogen be controlled in welding nickel? - CORRECT ANSWER=> By
using filler metal containing titanium."
2|Page
,"What is the most likely cause of porosity in carbon steel welds?
(a) hydrogen from reduction of water
(b) nitrogen
(c) carbon monoxide from reaction of oxygen with carbon
(d) oxygen direct from the air - CORRECT ANSWER=> (c)"
"What elements are included in electrodes or fluxes to control porosity in steel welds?
(a) silicon, aluminum, manganese
(b) copper, nickel, molybdenum
(c) sulphur, phosphorus, selenium
(d) silica, alumina, magnesia - CORRECT ANSWER=> (a)"
"What is thermal conductivity divided by specific heat and specific gravity known as? - CORRECT
ANSWER=> Thermal diffusivity"
"True or False?
A metal with a low thermal conductivity is more likely to reach the maximum melting efficiency
when welded. - CORRECT ANSWER=> True"
"Would a joint geometry designed for thick stainless steel be perfectly acceptable for welding
thick aluminum? - CORRECT ANSWER=> No. Grooves for thick aluminum would have a wider
angle than for stainless steel."
"When welding on a thick plate the cooling rate is proportional to the:
(a) heat input.
(b) inverse of the heat input.
(c) inverse of the square of the heat input. - CORRECT ANSWER=> (b)"
"From Figure 11.10(Module 20-2014, page 54), estimate the cooling rate for a submerged arc
bead on a 19 mm plate (no preheat) with an energy input of 1.77 kJ/in. - CORRECT ANSWER=>
16°C/s at 540°C"
"Which of the following metals is likely to need the greatest degree of shielding from the
atmosphere during welding?
(a) copper
(b) lead
(c) titanium
3|Page
, (d) steel
(e) gold - CORRECT ANSWER=> (c)"
"In an electroslag flux the current is carried mainly by:
(a) neutral oxides.
(b) holes.
(c) mobile ions.
(d) thermionic electrons.
(e) free electrons. - CORRECT ANSWER=> (c)"
"Compared with pure tungsten, a thoriated tungsten electrode is expected to:
(a) get hotter more quickly.
(b) absorb more electrons.
(c) have a shorten life.
(d) operate at a lower temperature for the same current.
(e) emit more ions. - CORRECT ANSWER=> (d)"
"The presence of close-packed planes in FCC metals gives many of them the special property of:
(a) good high-temperature strength.
(b) the ability to undergo extensive plastic deformation.
(c) brittleness at low temperatures.
(d) complete solubility with all other metals.
(e) small grains. - CORRECT ANSWER=> (b)"
"Work hardening occurs because of:
(a) fine precipitates.
(b) a reduction in the number of dislocations making slip more difficult.
(c) locking of dislocations by carbon and nitrogen atoms.
(d) multiplication and congestion of dislocations. - CORRECT ANSWER=> (e)"
"Nickel and copper have complete solid solubility. Copper has a lower melting point then nickel.
If a 50/50 Cu-Ni alloy is cooled from the liquid what will be the composition of the first solid to
form?
(a) 50% Cu
(b) less than 50% Cu
(c) Pure Cu
(d) Pure Ni
(e) more than 50% Cu - CORRECT ANSWER=> (b)"
4|Page
