The Full Form of GMAW is‍ Gas metal arc welding.

Gas metal arc welding (GMAW) is a high-speed, economical process that is sometimes referred to as metal inert gas (MIG) welding (Figure 1). In this process, an arc is struck between the base metal and a continuously supplied consumable electrode, which provides filler metal for the weld (2). The electrode is bare, containing no coating or core. The shielding, to protect the molten metal from reacting with constituents of the atmosphere, is supplied by an external gas, usually containing one of a mixture of the following: helium, argon, or carbon dioxide. A significant amount of fume can be generated when welding with this process. Most of the fume generated during GMAW is derived from the consumption of the electrode and not from the base metal.

GMAW is a welding process which joins metals by heating the metals to their melting point with an electric arc and the arc is struck between a continuous, consumable bare (not covered) electrode wire and the work piece; whereas the arc is shielded from atmospheric contaminants by a shielding gas. The shielding is accomplished by flooding the arc, melted end of the metal-electrode, and weldpool area with a shielding gas. The bare wire is fed continuously and automatically from a spool through the welding gun, Figure 10 illustrates the schematic representation of the GMAW process.