TIG welding is an arc welding process in a shielded environment, using neutral gases – argon or helium – and a non-fusible tungsten electrode that is not consumed.

This can be:

• pure tungsten electrode (for welding aluminium, copper and magnesium and their alloys);
• alloyed with thorium, zirconium or hafnium oxide (for welding high-alloy steels).

TIG welding is used for welding:

• alloy steel using alternating current and a positive pole at the electrode;
  non-ferrous metals by means of a direct electric current and a negative pole at the electrode.

TIG welding can be used to weld metals and alloys with extremely high melting points, as it can reach high temperatures of up to 6,000 degrees. The use of noble gas protects against atmospheric contamination or oxidation of the welding consumables, and the method itself offers greater control over the welding consumables compared to arc welding with coated electrodes, providing stronger and higher quality welds, while TIG welding does not result in any loss of material.

TIG welding is considered to be the highest quality welding process as it ensures that the weld is almost identical in composition to the workpiece, is extremely resistant to corrosion and is not susceptible to cracking, even over long periods of time.

TIG welding is very demanding as it requires a short arc distance, but offers the best possible results: strong, precise and high quality welds. It is used for welding pipelines, in toolmaking, and without it there would be no modern aviation or space programme. It is often used in industries where special hygiene standards are required – for example, cosmetics or food.