CWI Metallurgy and Weld Discontinuities 2

Question 1

Which weld discontinuity is caused by the base metal melting away beneath the weld toe, creating a groove along the weld edge?

Accepted Answer

Undercut

Answer

Overlap

Answer

Incomplete fusion

Answer

Cold lap

Question 2

In welding metallurgy, what does the term 'HAZ' refer to?

Accepted Answer

Heat-Affected Zone

Answer

High Alloy Zone

Answer

Hardened Arc Zone

Answer

Horizontal Arc Zone

Question 3

Which type of crack forms along the centerline of a weld bead due to solidification shrinkage and low-melting-point segregates?

Accepted Answer

Centerline solidification crack

Answer

Toe crack

Answer

Underbead crack

Answer

Lamellar tear

Question 4

What is the primary cause of porosity in a weld?

Accepted Answer

Gas entrapment during solidification

Answer

Excessive preheat temperature

Answer

High interpass temperature

Answer

Insufficient arc voltage

Question 5

Which discontinuity occurs when weld metal flows over the base metal surface without fusing to it?

Accepted Answer

Overlap

Answer

Underfill

Answer

Concavity

Answer

Burn-through

Question 6

In carbon steel, what phase transformation occurs when steel is rapidly cooled (quenched) from the austenite region?

Accepted Answer

Martensite formation

Answer

Ferrite formation

Answer

Pearlite formation

Answer

Bainite formation

Question 7

A weld inspector finds a discontinuity classified as 'incomplete joint penetration' (IJP). What does this mean?

Accepted Answer

The weld metal did not fully penetrate to the root of the joint

Answer

The weld bead is too wide

Answer

The cap pass is missing

Answer

The weld has excessive reinforcement