AWS AWS Weld Metallurgy & Heat Treatment

Question 1

The heat-affected zone (HAZ) in welding is defined as:

Accepted Answer

The base metal area altered by welding heat without melting

Answer

The area where filler metal has been deposited

Answer

The base metal area that has been melted during welding

Answer

The zone where weld spatter has been deposited

Question 2

Martensite in steel welds is:

Accepted Answer

A hard, brittle phase formed by rapid cooling of austenite

Answer

A soft, ductile phase that improves weld toughness

Answer

A phase that forms during slow controlled cooling

Answer

A protective oxide layer on the weld surface

Question 3

Carbon equivalent (CE) is used to predict:

Accepted Answer

The susceptibility of steel to hydrogen-induced cracking

Answer

The carbon content of the filler metal

Answer

The melting point of the base metal

Answer

The tensile strength of the completed weld

Question 4

Hydrogen-induced cracking (HIC) in welds is most likely to occur:

Accepted Answer

After the weld has cooled below 150°C (300°F)

Answer

During welding at elevated temperatures

Answer

Immediately after solidification of the weld pool

Answer

Only in non-ferrous metals

Question 5

Austenite in steel exists:

Accepted Answer

At elevated temperatures in a face-centered cubic structure

Answer

At room temperature in all steels

Answer

Only in stainless steels at all temperatures

Answer

Below the martensite start temperature

Question 6

Solidification cracking in welds is primarily caused by:

Accepted Answer

Low-melting-point impurities segregating to grain boundaries during solidification

Answer

Excessive preheat temperature

Answer

Low-temperature hydrogen embrittlement

Answer

Excessive post-weld heat treatment