23. Lis any three defects associated with fusion welding, anddescribe them briefly.
24. Draw a sketch of weld section, and label three zones; namely:base metal, weld metal and heat affected zone.
25. Define power density and include its units, and describe howpower density affects size of heat affected zone?
26. Sketch Fe-Fe3C equilibrium phase diagram, and identify thefollowing:
a. Alpha region
b. Gamma region
c. Delta region
d. Eutectic point
e. Eutectoid point
f. Lower critical temperature line, A1

27. Identify the methods that can be employed to minimize thedistortion in the welded workpieces.
28. Identify one high power density and one low power densitywelding process.
29. Sketch a fillet weld, and identify weld size, throat size andconvexity or concavity?
30. Two AISI1020 Steel plates 6 mm thick each are to be weldedthrough a T-Joint double fillet weld using
SMAW process. Assume that each leg of the fillet weld is equal to 4mm, and the weld has a flat face.
Perform the tasks:
a. How much metal in grams will be required to make the welds?Density of steel weld metal is 7.85
g/cm3.
b. How many electrodes will be required to make the weld ifdiameter of the electrode is 4 mm, and
length is 350 mm? Assume that electrode metal deposition efficiencyis 65%.