Metal Active Gas Welding
MAG welding is a consumable electrode arc process with active gas mixtures, widely used in steel construction and industrial series production.
Physicochemical Mechanism of Action
MAG welding uses a mixture of argon and carbon dioxide (MAG) as shielding gas. The argon shields the weld area from air and steel oxidation, while the carbon dioxide coats the steel surface and facilitates melting.
Metallurgical Relevance & Welding Risks
Insufficient gas flow can cause porosity because air enters the weld area. Too much carbon dioxide can increase weld hardness and lead to hot cracking. An incorrect gas ratio (argon to CO2) can affect the microstructure and reduce steel toughness.
Workshop Practice & Instructions
Always use a sufficiently high gas flow rate, typically 15-20 l/min. Ensure the gas mixing ratio (argon to CO2) is in the range of 80:20 to 90:10. Monitor the weld area temperature and allow the weld to cool slowly to achieve a homogeneous structure.