Shielding Gas Mixture with Carbon Dioxide
A CO2-containing shielding gas mixture consists of argon and reactive carbon dioxide. It improves sidewall fusion and increases heat input in MAG welding.
Physical and Chemical Mechanism of Action
The shielding gas mixture with carbon dioxide contains argon as a carrier substance and reactive carbon dioxide. The carbon dioxide reacts chemically with the metal, which activates the surface and improves the sidewall fusion.
Metallurgical Relevance & Risks in Welding
Using shielding gas mixtures with carbon dioxide leads to better weld seam quality through optimized sidewall fusion. However, too high a carbon dioxide content can lead to melting of the weld seam, which impairs strength.
Workshop Practice & Operating Instructions
For MAG welding, use a gas mixture of 75% argon and 25% reactive carbon dioxide. Make sure the carbon dioxide content is between 20% and 30% to ensure optimal heat input and sidewall fusion.