Plasma Gas Mixture

Physicochemical Mechanism of Action

The plasma gas mixture is used in TIG welding. The plasma gas (e.g., argon) forms the plasma, while the secondary gas (e.g., carbon dioxide) shields the weld pool and improves constriction.

Metallurgical Relevance & Welding Risks

Insufficient secondary gas can lead to porosity because it doesn't shield the weld pool enough. Too much secondary gas can impair constriction and lead to poor gas flow.

Shop Practice & Instructions

Use a plasma gas mixture with a ratio of 90% plasma gas and 10% secondary gas. Make sure the flow meter is set correctly (approx. 5-8 l/min). Monitor constriction and weld pool during welding.