FCAW-GS uses which type of shielding gas?

FCAW-GS, or Flux-Cored Arc Welding with Gas Shielding, primarily uses carbon dioxide (CO2) as its shielding gas. The function of the shielding gas in welding is to protect the molten weld pool from contamination by the atmosphere, which can introduce defects and compromise weld quality. CO2 is favored in FCAW-GS applications because it is cost-effective, readily available, and provides good penetration and stability in the welding arc.

In contrast, other gases listed would not be appropriate for this type of welding. Argon and helium are typically used for gas metal arc welding (GMAW) processes, while oxygen can lead to oxidation and is not suitable as a shielding gas in this context. Therefore, the specific application of CO2 in FCAW-GS is aligned with its role in enhancing weld performance and quality.