One question that many customers ask these days seems to be,  “What is the correct Tungsten Electrode to use for my application?”

Selecting the right tungsten is crucial to a successful TIG weld. You have to ensure the correct tungsten is used for the right type of power source, material to be welded, and the thickness of the material. With so many different types of tungsten electrodes available, learning how to properly select the correct tungsten for each application can greatly improve weld performance as well as saving time and money.

Below are some of the most commonly produced tungsten welding electrodes for TIG DC, TIG-AC, and Plasma welding:

2% THORIATED (RED) EWTh-2/WT20

Principal Oxide: 1.7–2.2% Thorium Oxide

Radioactive. Best for use in direct current (d/c) applications using transformer based constant current power sources. Best for use on non corroding steels, titanium alloys, nickel alloys, copper alloys. Good d/c arc starts and stability, medium erosion rate, medium amperage range, medium tendency to spit.

0.8% ZIRCONIATED (WHITE) EWZr-8/WZ8

Principal Oxide: 0.7– 0.9% Zirconium Oxide

Non-Radioactive. Best for use in alternating current (a/c) for aluminum alloys and magnesium alloys using inverter or transformer based constant current power sources. Balls well, handles higher amperage than pure tungsten with less spitting, better arc starts and arc stability than pure tungsten.

1.5% LANTHANATED (GOLD) EWLa-1.5/WL15

Principal Oxide: 1.3 –1.7% Lanthanum Oxide

Non-Radioactive. Best for use in direct current (d/c) as an alternative to 2% thoriated using inverter or transformer based constant current power sources. Best for non corroding steels, titanium alloys, nickel alloys, copper alloys. Best d/c arc starts and stability, low erosion rate, wide amperage range, no spitting.

2% CERIATED (GREY) (Formerly Orange) EWCe-2/WC20

Principal Oxide: 1.8–2.2% Cerium Oxide

Non-Radioactive. Best for use in alternating current (a/c) or direct current (d/c) applications using inverter or transformer based constant current power sources. Good for low-alloyed steels, non corroding steels, aluminum alloys, magnesium alloys, titanium alloys, nickel alloys, copper alloys. Good ignition and re-ignition properties, long service life, excellent arc stability. Low erosion rate, best at low amperage range, no spitting, good d/c arc starts and stability.

PURE (GREEN) EWP/WP

Principal Oxide: None

Non-Radioactive. Contains 99.50% tungsten. Good for use in alternating current (a/c) for aluminum alloys and magnesium alloys in low to medium amperage applications using transformer based constant current power sources only. Balls easy, tends to spit at higher amperages. Used for non-critical welds only.

2% LANTHANTED (BLUE) EWLa-2/WL20

Principal Oxide: 1.8 – 2.2% Lanthanum Oxide

Non-Radioactive. Best general purpose electrode for both alternating current (a/c) or direct current (d/c) using inverter or transformer based constant current power sources. Good for low-alloyed steels, non corroding steels, aluminum alloys, magnesium alloys, titanium alloys, nickel alloys, copper alloys. Good arc starts and stability, medium to high amperage range, low erosion rate.

LayZr™ (CHARTREUSE) EWG

Principal Oxides: 1.5% Lanthanum, 0.08% Zirconium, 0.08% Yttrium Oxides

Non-Radioactive. Best for automated or robotic applications in alternating current (a/c) or direct current (d/c) due to low voltage tolerance (changes in tip to work piece distance) using inverter or transformer based constant current power sources. Good for low-alloyed steels, non corroding steels, aluminum alloys, magnesium alloys, titanium alloys, nickel alloys, copper alloys. very stable tip geometry, runs cooler than 2% thoriated with longer life, low to medium amperage range. very best low amperage starts

Tungsten Preparation

Depending on the type of tungsten electrode, preparation of the tungsten consists of either  a balled, pointed, or truncated shape.  A balled tip is most commonly used on a pure tungsten electrode and is suggested for use with the AC process on sine wave and conventional Square Wave TIG welders. To properly ball the end of the tungsten, apply the AC amperage recommended for the electrode diameter and the ball on the end of the tungsten will form itself. The diameter of the balled end should not exceed 1.5 times the diameter of the electrode (for example, a 1/8-in. electrode should form a 3/16-in. diameter end), as having a larger sphere at the tip of the electrode can reduce arc stability and/or fall off and contaminate the weld.

In any application, the type and shape of tungsten you use helps determine the arc quality and welding performance you will achieve. Each of the above types of tungsten will bring certain advantages and disadvantages. That’s why, regardless of type of material or process you are using to TIG weld,  it is always important to be wise when choosing the tungsten for your application. With anything, it takes time to learn how to prepare and select tungsten electrodes for the application you are using. 

By following the above and with some practice, you will be able to learn how to pick the best tungsten electrode for your application and proper tungsten preparation.