361. Which two of the following joining processes are autogenous?
     i. Diffusion welding
     ii. Electroslag welding
     iii. Tungsten inert gas welding
     iv. Friction welding

1. 1. i and iv

   
   
   

   2. ii and iii

   
   
   

   3. ii and iv

   
   
   

   4. i and iii

   
   
   

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1. View Hint View Answer Discuss in Forum

   Autogeneous → No filter material is used so Diffusion welding & friction welding

   Correct Option: A

   Autogeneous → No filter material is used so Diffusion welding & friction welding

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362. Within the Heat Affected Zone (HAZ) in a fusion welding process, the work material undergoes

1. 1. micro structural changes but does not melt

   
   
   

   2. neither melting nor micro structural changes

   
   
   

   3. both melting and micro structural changes after solidification

   
   
   

   4. melting and retains the original micro structure after solidification

   
   
   

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1. View Hint View Answer Discuss in Forum

   Temperature is above the Recrystalization temperature due to which micro structural changes takes place

   Correct Option: A

   Temperature is above the Recrystalization temperature due to which micro structural changes takes place

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363. In solid-state welding, the contamination layers between the surfaces to be welded are removed by

1. 1. alcohol

   
   
   

   2. plastic deformation

   
   
   

   3. water jet

   
   
   

   4. sand blasting

   
   
   

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1. View Hint View Answer Discuss in Forum

   plastic deformation

   Correct Option: B

   plastic deformation

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364. The major difficulty during welding of aluminium is due to its

1. 1. high tendency of oxidation

   
   
   

   2. high thermal conductivity

   
   
   

   3. low melting point

   
   
   

   4. low density

   
   
   

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1. View Hint View Answer Discuss in Forum

   Aluminium oxide layer which is ceramic in nature has higher melting point which decreases the quality of welding.

   Correct Option: A

   Aluminium oxide layer which is ceramic in nature has higher melting point which decreases the quality of welding.

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365. Match the CORRECT pairs
     

     Processes	Characteristics/Applications
     P. Friction Welding	1. Non-consumable electrode
     Q. Gas Metal Arc welding	2. Joining of thick plates
     R. Electroslag Welding	3. Consumable electrode wire
     S. Tungsten Inert Gas welding	4. Joining of cylindrical dissimilar materials

1. 1. P-4, Q-3, R-2, S-1

   
   
   

   2. P-4, Q-2, R-3, S-1

   
   
   

   3. P-2, Q-3, R-4, S-1

   
   
   

   4. P-2, Q-4, R-1, S-3

   
   
   

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1. View Hint View Answer Discuss in Forum

   P-4, Q-3, R-2, S-1

   Correct Option: A

   P-4, Q-3, R-2, S-1

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