Inert Shielding Gas
Inert shielding gas like argon or helium protects the weld pool in TIG and MIG welding from oxidation. It does not react with the metal.
Physical-Chemical Mechanism of Action
Inert shielding gas such as argon or helium has high chemical inertness and does not form chemical bonds with the molten metal. It creates a dense layer around the workpiece that excludes atmospheric oxygen and water vapor molecules.
Metallurgical Relevance & Risks in Welding
Without inert shielding gas, oxidation occurs in the molten weld pool, leading to porosity and reduced mechanical properties. Insufficient shielding gas supply can cause hot cracking and poor weld quality.
Shop Practice & Action Instructions
Use a continuous gas supply with a flow of at least 15 L/min for argon or helium. Ensure the gas is directed properly to the weld and no air pockets form. Regularly check gas supply systems for leaks or blockages.