Which shielding gas is cheaper and more widely used than the other?

• A. Helium is cheaper than Argon
• B. Argon is more expensive than Helium
• C. Argon is cheaper than Helium
• D. Hydrogen is cheaper than Argon

Answer: (C)

Shielding gas selection in GTAW is driven by cost, availability, and arc behavior. Argon is the default shielding gas for most GTAW applications because it is readily available, relatively inexpensive, and provides a stable arc with good weld quality for a wide range of metals. Helium can deliver a hotter arc and deeper penetration, which is useful in certain situations, but its higher cost and limited supply make it less common. Hydrogen is used only in a few specialized cases and comes with safety and material compatibility concerns, so it isn’t a general alternative to argon. Therefore, Argon is cheaper and more widely used than Helium.