11. Match the joining processes in Group 1 with the filler material in Group 2.
Group 1
Group 2
P. Soldering
1. Silver-titanium alloy
Q. Welding
2. Silver-tin alloy
R. Brazing
3. Mild steel
4. Lead fluoride
| Group 1 | Group 2 |
| P. Soldering | 1. Silver-titanium alloy |
| Q. Welding | 2. Silver-tin alloy |
| R. Brazing | 3. Mild steel |
| 4. Lead fluoride |
12. Determine the correctness or otherwise of the following Assertion (a) and Reason (r).
Assertion (a): During welding of aluminium alloys by the gas tungsten arc welding process, direct current reverse polarity (DCRP) mode is used.
Reason (r): DCRP facilitate breaking up of the oxide film on the workpiece surface.
Assertion (a): During welding of aluminium alloys by the gas tungsten arc welding process, direct current reverse polarity (DCRP) mode is used.
Reason (r): DCRP facilitate breaking up of the oxide film on the workpiece surface.
13. "Cold cracking" in the heat affected zone of a high strength steel weld can take place because of
14. Steels with high carbon equivalent have poor weldability because in these steels during welding
15. Which of the following is not a fusion welding process?
16. Of the following welding processes
[P] Laser Beam Welding
[Q] Submerged Arc Welding
[R] Metal Inert Gas Welding
the width of the heat-affected zone in decreasing order is
[P] Laser Beam Welding
[Q] Submerged Arc Welding
[R] Metal Inert Gas Welding
the width of the heat-affected zone in decreasing order is
17. In TIG welding thoriated tungsten electrodes are used because it
18. In the consumable electrode shielded metal arc welding process, which of the following observations are correct?
P. The, weld composition does not depend upon the basicity of the slag.
Q. Basic flux is used to achieve low hydrogen content-and low inclusion content in the weld metal.
R. Reverse polarity of the direct current power source is used to weld thin sheets.
S. Coated electrodes are classified by tensile strength of the weld metal deposit.
P. The, weld composition does not depend upon the basicity of the slag.
Q. Basic flux is used to achieve low hydrogen content-and low inclusion content in the weld metal.
R. Reverse polarity of the direct current power source is used to weld thin sheets.
S. Coated electrodes are classified by tensile strength of the weld metal deposit.
19. In an arc welding experiment, the current, voltage and electrode travel speed were 140 A, 22 V, and 15 cm/min respectively. The heat input per unit length of the weld is given by . . . . . . . . kJ/cm.
20. Match the welding process in Group 1 with the source of heat in Group 2.
Group 1
Group 2
P. Ultrasonic welding
1. Thermochemical
Q. Spot welding
2. Electrical resistance
R. SMAW
3. Friction
S. Thermit welding
4. Electric arc
| Group 1 | Group 2 |
| P. Ultrasonic welding | 1. Thermochemical |
| Q. Spot welding | 2. Electrical resistance |
| R. SMAW | 3. Friction |
| S. Thermit welding | 4. Electric arc |