Tungsten Electrodes
Tungsten is a rare metallic element used for manufacturing TIG welding electrodes. The TIG
process relies on tungsten’s hardness and high-temperature resistance to carry the welding
current to the arc. Tungsten has the highest melting point of any metal, 3,410 degrees Celsius.
Tungsten electrodes are nonconsumable and come in a variety of sizes, they are made from
pure tungsten or an alloy of tungsten and other rare earth elements. Choosing the correct
tungsten depends on the material being welded, the amount of amps required and whether
you are using AC or DC welding current.
Follow are common used tungsten types: Thoriated, Ceriated, Lanthanated, Zirconiated
Tungsten Electrodes Rating for Welding Currents
Tungsten Diameter(mm)
DC Current Amps Torch Negative2% Thoriated
1.0mm
1.6mm
2.4mm
3.2mm
4.0mm
15 - 80
70 -150
150 - 250
250 - 400
400 - 500
Tungsten electrodes rating for welding currents
25
Tungsten Preparation
Always use DIAMOND wheels when grinding and cutting. While tungsten is a very hard
material, the surface of a diamond wheel is harder, and this makes for smooth grinding.
Grinding without diamond wheels, such as aluminum oxide wheels, can lead to jagged edges,
imperfections, or poor surface finishes not visible to the eye that will contribute to weld
inconsistency and weld defects.
Always ensure to grind the tungsten in a longitudinal direction on the grinding wheel. Tungsten
electrodes are manufactured with the molecular structure of the grain running lengthwise and
thus grinding crosswise is “grinding against the grain.” If electrodes are ground crosswise, the
electrons have to jump across the grinding marks and the arc can start before the tip and
wander. Grinding
longitudinally with the grain, the electrons flow steadily and easily to the end of the tungsten
tip. The arc starts straight and remains narrow, concentrated, and stable.
Table 6-1-1:Tungsten electrodes rating for welding currents
Repeat the process
Move the torch forward to the
front of the
molten pool
Gas shield
Retract the filler wire
Fig. 6-1-17: Retract the filler wire Fig. 6-1-18: Torch move Fig. 6-1-19: Repeat the process
Summary of Contents for Dura ARC160
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