Welding Questions on “Weldability”.
1. Which of the following is not included in weldability?
a) Ability of mechanical soundness
b) Serviceability of joint
c) Strain relieving brittleness
d) Metallurgical compatibility of metal
Answer: c
Clarification: For the making of good fabricated composition of a structure, metal with good weldability gets readily welded. Weldability includes the ability of the metal or the alloy to be having soundness in its mechanical properties, metallurgical compatibility of metal and serviceability of joint.
2. Which effect is not seen in alloys on weldability?
a) Control of ductile-malleable transformation temperature
b) Provision for oxidation to molten metal
c) Reduction in segregation
d) Grain refinement
Answer: b
Clarification: On weldability, there are some effects seen in the alloying elements. Some of them are Control of ductile-malleable transformation temperature, Reduction in segregation, Grain refinement and provision for deoxidation to the molten metal.
3. On which of the following factor, does weldability not depend?
a) Boiling point
b) Melting point
c) Thermal expansion
d) Thermal conductivity
Answer: a
Clarification: Weldability is dependent on five factors of the metal or alloying element. The factors being, melting point, thermal expansion, thermal conductivity, surface condition and change in the microstructure.
4. Which of the following is not a way of correcting the metal which does not have good weldability properties?
a) Procedure of welding
b) Provision of fluxing material
c) Provision of filler material
d) Procedure of adding filler materials
Answer: d
Clarification: When a particular metal or an alloy does not have desirable welding characteristics, then it can be corrected by proper fluxing material, correct filler material and a perfect welding procedure.
5. What does HAZ stand for?
a) Helium Aerated Zone
b) Heated Area Zone
c) Heat Affected Zone
d) Heat Allowed Zone
Answer: c
Clarification: HAZ stands for Heat Affected Zone. This zone is generally the base of the metal or a thermoplastic material. This zone is not melted but the properties are altered by the welding process.
6. With an increase in the heat input of arc welding method, how does it affect the welding speed?
a) Increases
b) Decreases
c) Remains same
d) No relation
Answer: b
Clarification: In arc welding processes, for calculating the efficiency, we use the formula for heat input. According to the formula, heat input is inversely related to the speed of welding, that is, with an increase in heat input, the welding speed decreases.
7. With an increase in the heat input of arc welding method, how does it affect the voltage applied?
a) Increases
b) Decreases
c) Remains same
d) No relation
Answer: a
Clarification: None.
8. With an increase in the heat input of arc welding method, how does it affect the required current?
a) Increases
b) Decreases
c) Remains same
d) No relation
Answer: a
Clarification: None.
9. In fusion welding, welded pieces are kept together under pressure.
a) True
b) False
Answer: b
Clarification: In fusion welding, the welded pieces are not kept under pressure, instead they are welded first and then allowed for some to cool down. It is in pressure welding, that the welded pieces are kept under pressure for some time.
10. Materials having high thermal conductivity are difficult to melt.
a) True
b) False
Answer: a
Clarification: Materials that have a medium melting point are considered to be welded easily and those materials which have their thermal conductivity very high are the toughest to be melted.
Welding for Freshers,