scope:

Magnesium alloys can be arc welded with most of the same techniques and equipment used to arc weld steel or aluminum. Two types of arc-welding equipment, tungsten-metal arc (TIG) and gas-metal arc (MIG), are useful for welding all thicknesses of magnesium alloys using a variety of joint types. There is no more danger of fire occurring when arc-welding magnesium than with aluminum since the molten pool and base material do not ignite from the heat of the arc. A wide selection of magnesium alloys which can be arc welded are available as casting, extrusion or rolled products. High temperature magnesium alloys for service up to 800F are also rated excellent in weldability by arc welding. Several magnesium alloys can be arc welded and put into service without post heating for stress-relief. Some alloys, however, are subject to stress-corrosion cracking and must be stress-relieved after welding. This report presents technical information on both magnesium alloys and the arc-welding processes used to join them. This information amplifies those points pertaining to processes, alloys, welding wires and techniques which are most instructive in establishing the starting point for a number of different magnesium welding applications. A selected list of published reports, bulletins and specifications pertaining to the joining of magnesium alloys complements this technical information.