Tungsten has high melting point, strong electron emission ability, high elastic modulus and low vapor pressure, so tungsten electrode was used as thermal electron emission material early.
The shape of tungsten electrode tip is an important factor for TIG.

Tungsten welding electrode has excellent welding performance, great arc starting capacity with good arc stability, low electrode burning loss, long service life, free of slag and splashing and high welding quality.
Tungsten electrode plays an important role in tungsten argon arc welding of arc, arc stability and welding quality.

Tungsten electrode is used for inert gas protection arc welding, plasmacutting, spray-coating and furnace melting.
Surface conditions of tungsten electrode:
Grinding, cleaning, electrolysis polishing, drawing or forging.

Type	compositions				colors
	added oxide%	substances	substances%	tungsten%
W			<0.20	99.8	green
WT4	0.35--0.55	THO2	<0.20	remaining	blue
WT10	0.8--1.20	THO2	<0.20	remaining	yellow
WT20	1.70--2.20	THO2	<0.20	remaining	red
WT30	2.80--3.20	THO2	<0.20	remaining	violet
WT40	3.80--4.20	THO2	<0.20	remaining	orange
WZ3	0.15--0.50	ZrO2	<0.20	remaining	brown
WZ8	0.70--0.90	ZrO2	<0.20	remaining	white
WL10	0.90--1.20	LaO2	<0.20	remaining	black
WC20	1.80--2.20	CeO2	<0.20	remaining	grey

Diameter	Length
1.0	150                   175
1.6
2.0
2.4
3.2       6.3
4.0       8.0
5.0     10.0