Gas Tungsten Arc Welding (GTAW/TIG) Flashcards
6 cards from real AWS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Gas Tungsten Arc Welding (GTAW/TIG) flashcards as text
What type of tungsten electrode is most commonly recommended for welding aluminum using AC current in GTAW?
Answer: Pure tungsten (EWP)
Pure tungsten (EWP) is traditionally recommended for AC GTAW on aluminum because it forms a balled end that aids in oxide cleaning during the electrode positive half-cycle.
In GTAW, what is the primary function of the post-flow shielding gas after the arc is extinguished?
Answer: Cool the tungsten electrode and protect the solidifying weld pool and hot tungsten from oxidation
Post-flow shielding gas protects both the hot tungsten electrode and the solidifying weld pool from atmospheric contamination (oxidation and nitridation) until they cool below the temperature at which oxidation occurs.
Which shielding gas is most widely used for GTAW on carbon and low-alloy steels?
Answer: 100% Argon
100% Argon is the most widely used shielding gas for GTAW on carbon and low-alloy steels because it provides stable arc characteristics and adequate shielding at a lower cost compared to helium.
What AWS classification covers filler metals used in GTAW of carbon steel?
Answer: AWS A5.18
AWS A5.18 covers carbon steel filler metals for gas shielded arc welding, including GTAW rods such as ER70S-2 and ER70S-6.
In GTAW, what condition is indicated when the tungsten electrode becomes contaminated with base metal (appears gray or has inclusions)?
Answer: The electrode dipped into the weld pool
Tungsten contamination with base metal material occurs when the electrode tip makes contact with (dips into) the molten weld pool, transferring base metal into the tungsten and requiring re-preparation of the electrode.
Which GTAW technique is preferred when welding in the overhead position to minimize the risk of weld pool sag?
Answer: Reduce amperage and use a smaller weld pool with faster travel speed
In overhead GTAW, reducing amperage to keep the weld pool small and increasing travel speed minimizes the volume of molten metal that gravity can pull away from the joint, reducing sag.