Definition
A type of electric arc welding in which the arc is struck between a non-consumable tungsten electrode and the workpiece, while a shield of inert gas (typically argon or helium) flows around the arc to protect the weld area from atmospheric contamination. Filler metal, when used, is added separately by hand. Now more commonly called Gas Tungsten Arc Welding (GTAW), or informally TIG welding.
Plain English
A precise welding method that uses a tungsten rod to create the arc and a flow of unreactive gas to keep air away from the hot metal so the weld stays clean. The welder feeds in filler metal by hand if needed.
Context Anchor
Seen in aircraft maintenance and repair discussions, especially where clean, controlled welds are needed on aluminum, stainless steel, or other aircraft metals.
Derivation
Named for its two key features: the tungsten electrode (which has an extremely high melting point, so it doesn't burn away during welding) and the inert gas shield (a gas that won't chemically react with the hot metal). Together they describe exactly how the process works.
Why Pilots Care
Produces high-quality, contamination-free welds essential for maintaining the strength and safety of critical airframe parts.
Intuition Check
Do not read “Tungsten Inert Gas” as a kind of gas made from tungsten. Tungsten is the electrode material; the inert gas is the protective gas flowing around the weld.
Example Sentence 1
The cracked engine mount was repaired using Tungsten Inert Gas welding to preserve the strength of the thin steel tubing.
Example Sentence 2
Tungsten Inert Gas welding allows precise heat control when joining thin aluminum sheets on the fuselage.