Fundamentals Tech Flashcards

What does the acronym 'HAZ' stand for in welding metallurgy?

Answer: Heat-Affected Zone

The Heat-Affected Zone (HAZ) is the area of base metal whose microstructure and properties have been altered by welding heat without melting.

Which nondestructive examination method is best suited for detecting subsurface planar discontinuities in a weld?

Answer: Ultrasonic testing (UT)

Ultrasonic testing (UT) can detect subsurface discontinuities including planar flaws like lack of fusion and cracks.

What is the purpose of the 'essential variable' concept in welding procedure qualification?

Answer: To identify parameters whose change requires requalification of the WPS

Essential variables are those parameters whose change could affect the mechanical properties of the weld, requiring the WPS to be requalified.

In radiographic testing, a higher density (darker area) on a film indicates the presence of:

Answer: Less material or void-type discontinuities

Darker (higher density) areas on RT film indicate less material for radiation to penetrate, suggesting voids, porosity, or cracks.

Which of the following is considered an 'unacceptable' weld profile condition per AWS D1.1?

Answer: Overlap (cold lap) at the weld toe

Overlap (cold lap) is unacceptable because it creates a notch at the weld toe that can initiate fatigue cracks without proper fusion.

What is 'dilution' in welding?

Answer: The mixing of base metal into the weld metal deposit

Dilution is the percentage of base metal melted into the weld pool, which changes the chemical composition of the deposited weld metal.

A Procedure Qualification Record (PQR) is defined as:

Answer: A document that records actual welding conditions used to qualify a WPS

A PQR is the record of welding data and test results used to support and qualify a Welding Procedure Specification (WPS).