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 HAZ is the portion of the base metal that was not melted but whose microstructure and mechanical properties were altered by the heat of welding.

Question 2

Martensite in steel welds is:

Accepted Answer

A hard, brittle phase formed by rapid cooling of austenite

Answer

Martensite is a hard, brittle microstructure that forms when austenite is cooled too rapidly, and can lead to cracking in the HAZ.

Question 3

Carbon equivalent (CE) is used to predict:

Accepted Answer

The susceptibility of steel to hydrogen-induced cracking

Answer

Carbon equivalent is a formula combining carbon and other alloying elements to predict hardenability and susceptibility to hydrogen-induced cracking.

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

Hydrogen-induced cracking (cold cracking) typically occurs after the weld cools below 150°C because hydrogen diffuses to stress concentration areas as the metal becomes more brittle.

Question 5

Austenite in steel exists:

Accepted Answer

At elevated temperatures in a face-centered cubic structure

Answer

Austenite is the high-temperature face-centered cubic (FCC) phase of steel that exists above the critical transformation temperature.

AWS Practice Test

AWS Practice Test

AWS AWS Weld Metallurgy & Heat Treatment