CO2 shielding gas is classified as which type of shielding gas?

CO2 shielding gas is classified as which type of shielding gas?

• A. Inert gas.
• B. Reactive gas.
• C. Ionized gas.
• D. Non-conductive gas.

Answer: (B)

Shielding gases are classified by how they interact chemically with the molten metal. CO2 is a reactive gas because it can participate in chemical reactions at welding temperatures, oxidizing the weld pool and altering heat transfer. This reactivity changes bead shape, penetration, and can increase spatter compared with inert gases. Inert gases (like argon or helium) do not chemically react with the weld, providing cleaner, more stable welds. Terms like ionized gas or non-conductive gas describe electrical behavior in the arc, not the chemical reactivity used for shielding gas classification, so they aren’t the right way to categorize CO2.

Shielding gases are classified by how they interact chemically with the molten metal. CO2 is a reactive gas because it can participate in chemical reactions at welding temperatures, oxidizing the weld pool and altering heat transfer. This reactivity changes bead shape, penetration, and can increase spatter compared with inert gases. Inert gases (like argon or helium) do not chemically react with the weld, providing cleaner, more stable welds. Terms like ionized gas or non-conductive gas describe electrical behavior in the arc, not the chemical reactivity used for shielding gas classification, so they aren’t the right way to categorize CO2.