MIGMAG

MIG/MAG welding is a welding process that uses a continuously fed consumable wire electrode and a shielding gas to protect the weld pool from atmospheric contamination. The acronym MIG stands for Metal Inert Gas and MAG for Metal Active Gas. In practice, MIG and MAG are both variants of gas metal arc welding (GMAW) and are usually performed with the same equipment; the difference lies in the shielding gas: inert gases (MIG) versus active gases such as CO2 or blends that include oxygen (MAG). The shielding gas protects the molten weld metal from oxidation and nitrogen uptake.

During the process, an electric arc is struck between the continuously fed wire electrode and the workpiece. The arc heats and melts both the wire and a portion of the base metal, creating a weld pool. The wire is fed automatically by a wire feeder, and the shielding gas is delivered through a nozzle around the arc. The power source can be constant-current or constant-voltage, and the process is typically operated with direct current, though some MAG variations can use alternating current.

MIG/MAG welding is widely used for ferrous and nonferrous metals, with common applications in automotive, fabrication, shipbuilding, and piping. It offers high deposition rates, good welding speed, and suitability for automation and thin-to-medium thickness sections. Limitations include sensitivity to wind in outdoor conditions due to shielding gas, a need for clean, rust-free surfaces for best results, and a tendency to produce more spatter on certain materials compared with other welding processes.