The most common of the reactive gases used in MIG welding is Carbon Dioxide (CO2). It is the only one that can be used in its pure form without the addition of an inert gas. CO2 is also the least expensive of the common shielding gases, making it an attractive choice when material costs are the main priority.
A 75/25 MIG Argon and CO2 mix is the most popular gas for MIG welding sales, making up more than 90% of the gas we sell at Vern Lewis Welding Supply. CO2 is much cheaper than inert gas, and it allows the bond to penetrate very deeply into the metal when welding.