Shielding Gas For Welding Aluminum. Shielding gases are necessary for gas metal arc welding to protect the welding area from atmospheric gases such as nitrogen and oxygen which can cause fusion defects porosity and weld metal embrittlement if they come in contact with the electrode the arc or the welding metal. And thats why its called shielding gas.
We know that the shielding gas is mainly Ar and CO2 used in TIG welding in many applications O2 H₂ He or N₂ can be added to improve the welding quality. Again many welding supply stores carry their own mixture that can improve the weld quality and ease of welding on stainless steel. Shielding gases are necessary for gas metal arc welding to protect the welding area from atmospheric gases such as nitrogen and oxygen which can cause fusion defects porosity and weld metal embrittlement if they come in contact with the electrode the arc or the welding metal.
For a pure 100 percent argon shield gas a flow rate of 20 to 30 cubic feet per hour is recommended when welding aluminum.
Mixtures of argon and helium are probably the next common and pure helium is generally only used for some specialized GTAW applications. The major purpose of MIG welding gas is to protect the arc and the molten weld pool from elements in our atmosphere that can contaminate and weaken the finished weld. For a pure 100 percent argon shield gas a flow rate of 20 to 30 cubic feet per hour is recommended when welding aluminum. Again many welding supply stores carry their own mixture that can improve the weld quality and ease of welding on stainless steel.