MIG (Metal Inert Gas) Welding is a form of Gas metal arc welding (GMAW), an arc welding process where a wire electrode and a shielding gas are fed through a welding gun. MIG is the most common industrial welding process, preferred for its versatility and speed. Originally developed for welding aluminum and other non-ferrous materials in the 1940s, GMAW was soon applied to steels because it allowed for lower welding time compared to other welding processes. The cost of inert gas limited its use in steels until several years later, when the use of semi-inert gases such as carbon dioxide became common.

MIG welding can be used on all thicknesses of steels, on aluminum, nickel, and even on stainless steel, etc. However, it is most typically utilized in manufacturing and in commercial fabrication settings.

Advantages of MIG welding are:

• High quality welds can be produced much faster
• Since a flux is not used, there is no chance for the entrapment of slag in the weld metal resulting in high quality welds
• The gas shield protects the arc so that there is very little loss of alloying elements. Only minor weld spatter is produced
• MIG welding is versatile and can be used with a wide variety of metals and alloys
• The MIG process can be operated several ways, including semi and fully automatic