GTAW, also known as Tungsten Inert Gas (TIG) welding, is an arc welding process that uses a non-consumable tungsten electrode to produce the weld. The weld area and electrode are protected from oxidation or other atmospheric contamination by an inert shielding gas (argon or helium). A filler metal is normally used, though some welds, known as autogenous welds, do not require it.
Advantages
- No flux required, so no slag
- All position welding
- Suitable for thin metals
- High-quality root
Limitations
- Slow welding speed
- Tungsten inclusion possibility in weld metal
- Requires inert gas shielding and purging
- Highly skilled welder required
Electrodes
| MATERIAL | TYPICAL ELECTRODE |
|---|---|
| CS/MS | ER70S-2 |
| SS | ER308L |
| CS#SS | ER309L |
| CS#C276 (HASTELLOY) | ERNiCrMO-4 |
Equipment Cost: Relatively Costly
Welding Speed: Slow
