Employing the MIG welding method is an efficient way to weld cast aluminum. Welding cast aluminum with the TIG welding method is also acceptable and just as efficient if not more efficient than MIG welding. In welding, electricity is streamed down onto the workload through an electrode, heating it to a point where the metal becomes a liquid. When the liquid cools, it hardens and permanently joins pieces of a metal together.
The acronym "MIG" in MIG welding stands for "metal inert gas." In MIG welding, an electrode is fed to the aluminum workload through a live stream, or arc, of electricity, leaving a fill metal on the workload. The electrode melts onto the workload, effectively welding pieces of cast aluminum together.
The acronym "TIG" in TIG welding refers to "tungsten inert gas." In TIG welding, the welder can apply the same process as in MIG welding, with the electrode melted onto the workload. However, in TIG welding, a different electrode may be employed, one that does not melt onto the workload. If this type of electrode is used, two pieces of cast aluminum are melted together by the application of a live arc of electricity; no filler metal is applied to the workload.