Co2 Gas For Welding. As individual welding gases, helium, argon, and carbon dioxide can create a quality weld. The deep penetration of pure co2 makes it useful for welding thick materials, as it provides very deep penetration.
The most common mixed gas for shielding in welding is a co2 argon mix. Carbon dioxide allows deep penetration, and argon is the inert gas that creates a better shield. Welding of carbon steel can be done with carbon dioxide alone and it produces the deepest penetration, the most smoke and the roughest weld.