TIG

TIG, short for Tungsten Inert Gas welding, is a welding process that uses a non-consumable tungsten electrode to create an arc between the electrode and the workpiece. The weld area is shielded by an inert gas, typically argon or sometimes helium, to protect the molten metal from atmospheric contamination. The process may use a filler metal added separately with a filler rod, or it can weld without filler depending on the joint and material.

The technique offers precise control of heat input and can produce high-quality, clean welds with good appearance. It is versatile across a wide range of metals, including aluminum, stainless steel, carbon steel, copper and its alloys, nickel, titanium, and other exotic alloys. TIG is particularly well suited for thin sections, critical joints, and applications requiring strong, leak-tight welds. Successful use often depends on careful joint preparation, clean surfaces, and skilled technique. Alternating current is commonly used for aluminum and magnesium to help break up oxide layers, while direct current is often used for steels and nickel alloys. Pulsed TIG can reduce heat input and distortion in some applications.

Equipment and setup typically include a suitable power supply (capable of DC or AC output), a TIG torch with a tungsten electrode, a shielding gas supply with regulator, and a filler rod if needed. Some setups employ water cooling for high-amperage work, and operators may use a foot pedal or other control to adjust amperage during welding. Safety measures include proper ventilation, UV protection, and electrical safety.

History and usage: TIG welding was developed in the mid-20th century and has since become a standard method in aerospace, automotive, and metal fabrication due to its precision and versatility.