Tungsten Electrode For Tig Welding

About Tungsten Electrode for TIG Welding:-

An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte or a vacuum). The word was coined by the scientist Michael Faraday from the Greek words elektron (meaning amber, from which the word electricity is derived) and hodos, a way.

Application:
Tungsten Electrode for TIG welding:
Tungsten electrodes are used when arc welding with the Tungsten Inert gas (TIG) process or when plasma welding. In both processes the electrode, arc and weld pool are protected from atmospheric contamination by an inert gas. A tungsten electrode is used because it can withstand very high temperatures with minimal melting or erosion.A TungstenA electrodes are made by powder metallurgy and are formed to size after sintering.
TIG welding tungsten electrodes usually contain small quantities of other metallic oxides which can offer the following benefits:-
facilitate arc starting
increase arc stabilityA
improve current-carrying capacity of the rod.
reduce the risk of weld contaminationA
increase electrode life
Oxides used are primarily those of zirconium, thorium, lanthanum, yttrium or cerium. Additions are usually of order 1%-4%. All these oxides greatly improve arc initiation, especially when direct current (DC) welding is employed. Thorium oxide (thoria) has been used for many years having been found effective in terms of long life and thermal efficiency. Zirconium oxide (zirconia) has been commonly used for alternating current (AC) TIG welding, normally for welding aluminium.
TypeBrandColorChemical Compositioni i i Sizes
(mm)SurfaceFeatures
Rare EarthImpuritiesW
Pure
TungstenWPGreeni a 0.05the rest0.8~15D,E
G,SNon-radioactive;suitable for AC welding of aluminum, magnesium, and their alloy
Thoriated
TungstenWTh10Yellow0.9~1.1ThO2a 0.05the rest0.8~15D,E
G,SExcellent electron emission and overall performances; high current-carrying capacity; radioactivity; suitable for DC welding of carbon steel, stainless steel,nickel alloy and titanium alloy.
WTh20Red1.8~2.2ThO2a 0.05the rest0.8~15
Lanthanum
TungstenWLa10Black0.8~1.2La2O3a 0.05the rest0.8~15D,E
G,SNon-radioactive;excellent electric conductivity and welding capacity; high current-carrying capacity; minimum ratio of burnt area; substitute for thoriated tungsten electrode; mainly used in DC welding.
WLa15Golden
Yellow1.3~1.7 La2O3a 0.05the rest0.8~15
WLa20Blue1.8~2.2 La2O3a 0.05the rest0.8~15
Cerium
TungstenWCe10Pink0.8~1.2CeO2a 0.05the rest0.8~15D,E
G,SNon-radioactive;easier arc initiation under low current circumstances, and low arc-maintaining current;suitable for the welding of pipelines,small components and discontinuous welding.
WCe15Orange1.3~1.7CeO2a 0.05the rest0.8~15
WCe20Grey1.8~2.2CeO2a 0.05the rest0.8~15
Yttrium
TungstenWY20Sky
Blue1.8~2.2Y2O3a 0.05the rest0.8~15D,E
G,SNon-radioactive;long and slim arc beam with high compression; deeper burning groove under medium and high current circumstances.
Compound
Rare Earth
TungstenWMXCyan1.0~5.0MOxa 0.05the rest0.8~15D,E
G,SCompound rare-earth tungsten electrode; different additives contributing to better performance of tungsten electrode
Note:Da As DrawnA A A A Ea Electrolytic PolishedA A A Ga GroundA A A A A Sa Swaged