MIG BrazingMIG brazing is a variation of the MIG welding process that is used for joining ferrous alloys. It uses the heat generated by an arc struck between a continuously fed consumable filler wire and the workpiece to fuse the metal in the joint area. The consumable wire used in MIG brazing is solid and an additional shielding gas is required to protect the arc and weld area in the same manner as that used for MIG welding. The main features of the process are low welding currents, low heat input and high deposition rates. The process is applied mainly to mild and alloy steels in automotive industry. Here, the MIG brazing process has largely superceded gas brazing and 'leading' processes in car production plants where it can greatly increase productivity. However, the process may also be used wherever welds with minimal dilution, but good fusion, are required. The filler wire is usually of copper-silicon alloy, although other copper alloy wires have also been used. Shielding gases are normally pure argon or argon-helium mixtures, although active gases have been used on occasions. The low currents used keep generation of welding fume down to low levels.
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