CWB Welding Inspector Level III Study Guide
Questions With Correct Answers
Which |of |the |following |metals |has |the |highest |thermal |conductivity?
(a) |carbon |steel
(b) |stainless |steel
(c) |aluminum |- |CORRECT |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. |- |CORRECT |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. |- |CORRECT |ANSWER✔✔-True
Electricity |can |be |conducted |by:
(a) |atoms |and |electrons.
(b) |electrons |and |ions.
(c) |only |ions. |- |CORRECT |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 |- |CORRECT |ANSWER✔✔-(b)
Thoria |is |added |to |tunsten |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)
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)
Which |of |the |following |elements |are |most |likely |to |form |interstitial |solid |solutions?
(a) |copper
(b) |nickel
(c) |carbon |- |CORRECT |ANSWER✔✔-(c)
Questions With Correct Answers
Which |of |the |following |metals |has |the |highest |thermal |conductivity?
(a) |carbon |steel
(b) |stainless |steel
(c) |aluminum |- |CORRECT |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. |- |CORRECT |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. |- |CORRECT |ANSWER✔✔-True
Electricity |can |be |conducted |by:
(a) |atoms |and |electrons.
(b) |electrons |and |ions.
(c) |only |ions. |- |CORRECT |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 |- |CORRECT |ANSWER✔✔-(b)
Thoria |is |added |to |tunsten |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)
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)
Which |of |the |following |elements |are |most |likely |to |form |interstitial |solid |solutions?
(a) |copper
(b) |nickel
(c) |carbon |- |CORRECT |ANSWER✔✔-(c)
