Difference Between MIG and TIG Welding

MIG vs TIG Welding

MIG and TIG welding are two types of arc welding, using metal electrodes and an inert gas as the shielding from oxidation at high temperatures.  Both types of welding are relatively easy to learn, and the welding processes can be performed on all the common materials.

What is MIG welding?

MIG stands for metal inert gas welding and also called metal active gas welding (MAG) or Gas metal arc welding (GAMW).  It is an arc welding method using a consumable metal electrode and a shielding gas is used to cover the welding area covered from the atmospheric oxygen and other contaminants. It was originally discovered for welding aluminium, but later developed to weld other metals. Also, MIG welding gives a faster rate of welding than other welding processes.   

MIG welding uses an electric arc to heat the metal and join the pieces. In MIG welding the electrode acts as the filler which is spent, and deposited on the welding area. The operation can be either automatic or semi automatic. The main gas used for the shielding is the Argon (Ar) gas, sometimes combined with carbon dioxide depending on the application.

Advantages of the MIG welding are user friendly and quickness of the welding process. Also, it is cheaper than the TIG welding process. MIG electrodes produce a less stable arc; hence the reliability of weld sections becomes an issue. More fumes, sparks, and smoke is created during the welding; thus making the process less cleaner.

What is TIG welding?

TIG stands for Tungsten Inert Gas welding, where the electrode used in the welding is specifically a Tungsten (W) electrode, and only the Argon gas is used. Even though the overall mechanism of the welding process is same as the MIG welding, TIG has a fundamental difference in the filling. Since the electrode is non-consumable, the filler has to be provided externally, or else, when welding thinner metal sheets, no filler is used.

In operation, the TIG welding is a semi-automatic process where the arc is controlled by a foot pedal.  TIG welding is usually employed in non- ferrous metal joining, but can be used for iron alloys too.

The tungsten electrode is used to reduce the amount of contamination during the welding process. The current from the tungsten electrode creates less sparks and fumes, so the weld is cleaner than that of MIG welding. Since contamination is lower, the precision of the welds is also higher. However, the complexity of the welding process and the cost are major drawbacks in the TIG welding against MIG welding, where the welder has to be proficient. Also, the setup requires more time and effort.  

What is the difference between MIG and TIG Welding?

• In MIG welding, the electrode used is basically the same metal being weld while, in TIG, it is specifically a tungsten electrode.

• MIG welding electrodes are consumable and act as the filler, while TIG electrodes are non-consumable and the filler has to be provided externally.

• The shielding gas used in the MIG is Argon sometimes mixed with carbon dioxide, wherein TIG only uses Argon gas.

• MIG welding is used for non-ferrous alloys but can be used for steel welding, whereas TIG welding can be used for any metal.

• TIG welding requires more practice than the MIG welding, because of the complexity and the tighter tolerances to be maintained, while the MIG welding is much more user friendly.

• TIG welding is cleaner than the MIG welding and involves less contamination.