problem 1:

Make a distinction between porosity and blow holes?

problem 2:

Illustrate the causes for formation of porosity in welds?

problem 3:

What are the situations required for the phase change in structures due to welding?

problem 4:

Illustrate the mechanism for the formation of heat affect zone in welds?

problem 5:

What are the constituents employed to coat on bare electrodes? Illustrate each of the ingredients?

problem 6:

Make a distinction between AC welding and DC welding?

problem 7:

Austenitic Stainless Steels are successfully welded through spot welding. Comment on this line.