Selecting the proper tungsten electrodes will greatly improve weld quality and productivity while lowering costs for your Gas Tungsten Arc Welding (GTAW/TIG) and Plasma Arc welding operations.  Additionally, by selecting High-Quality Tungsten Electrodes you'll Maximize Arc Starting and  Improve Arc Time

Choose electrodes from a trusted source

Although tungsten electrodes may look the same from one company to another, high-quality tungsten has been manufactured to ensure a very small grain structure which allows for better migration of oxides to the tip.

With high-quality tungsten, you'll also experience easier arc starting, improved arc time and better weld quality with minimized contamination.

Determine the best tungsten / tungsten alloy for your application

Since the development of the TIG welding process, many improvements have been made in the production of electrodes.  Most significantly is the addition of oxides to pure tungsten, creating tungsten alloys that provide the same level of emission as pure tungsten at much lower temperatures, improving the arc time of the electrode, and improving arc stability.

Each oxide has a different physical characteristic effecting tungsten performance. Electrodes are color coded, indicating the type of oxide used in the mix.  Note that color-coding is not standardized for all mixes and varies from the U.S. to Europe and Japan.

For most hand-held welding operations, ARC-ZONE recommends the ArcTime™ All-Purpose Tungsten Electrode.  For other applications, particularly automated welding, the best way to determine which tungsten alloy is best suited for your application is through testing.  The following list is provided as a guide.

ArcTime(TM) All-Purpose Tungsten Electrodes

This non-radioactive state-of-the-art formula combines three materials with tungsten to produce the best all-purpose tungsten electrode on the market.  Experience reliable arc starting even after numerous ignitions. Sometimes referred to as "rare earth" tungsten.

Color Code: Light Blue (US) Not standardized.

4% Thoriated

This radioactive tungsten formula is not commonly used.

Color Code:  Not standardized in US or Japan.  Orange (Europe)

2% Thoriated

This formula is a popular general purpose electrodes due to the excellent arc behavior and good tip life.  This is a radioactive formula, however.  Vapors, grinding dust and disposal of thorium dioxide raise health, safety and environmental concerns. Use only when contractually required by FAR specification.

Color Code: Red (US, Europe and Japan)

2% Lanthanated

This formula is a good general purpose non-radioactive replacement for 2% Thoriated. It has excellent ignition performance, low-burn-off rate, excellent re-ignition, and good service life.

Color Code: Blue (US) Not standardized in Europe. Yellow-Green (Japan)

1.5% Lanthanated

Another good general-purpose non-radioactive replacement for 2% Thoriated, and similar in performance to 2% lathanated.  It features excellent ignition and re-ignition properties and good service life.

Color Code: Gold (US) Not standardized in Europe or Japan.

1% Lanthanated

This non radioactive tungsten formula is not commonly used.

Color Code: Black (US, Europe and Japan)

2% Ceriated

Good for low-amp, DC orbital tube, pipe, thin sheet, and small part applications, this formula offers low current capacity, low arc ignition, good arc stability.

Color Code: Orange (US)  Gray (Europe and Japan)

I% Zirconiated

Used for radiographic-quality welding where tungsten contamination must be minimized. Balls-up easily in AC applications, good arc starting and current capacity.

Color Code: Brown (US)  White (Europe)  Not standardized in Japan.

Pure Tungsten

Pure tungsten has a high work-function which makes it difficult to start and maintain a stable arc. High burn-off rate result in short service life.

Color Code: Green (US, Europe and Japan)

Again, purchasing from a trusted source is important as manufacturing methods can greatly affect tungsten electrode performance.

Select the proper size

Tungsten is generally sold in packages of 10 pieces in a variety of standard diameters from .010” to .250” and in lengths of 3, 6, 7, 12, 18 and 24 inches. The most common length is 7.00"(175mm). The most common diameters are:  .040" (1.0mm), 1/16" (1.6mm), 3/32" (2.4mm), I/8" (3.2mm), 5/32" (4.0mm), and 3/16" (4.8mm)

Electrode diameter affects welding performance and weld bead shape. Again, the best way to determine which tungsten is best suited for your
application is through testing, however, the following should serve as a general guide:

Electrode Diameter:  0.020" (0.50mm)
Direct Current A: Straight Polarity | DCEN : 5-2
Direct Current A: Reverse Polarity | DCEP : n/a
Alternating Current, A: Unbalanced Wave: 5-15
Alternating Current, A: Balanced Wave : 10-20

Electrode Diameter:  0.040" (1.0mm)
Direct Current A: Straight Polarity | DCEN : 15-80
Direct Current A: Reverse Polarity | DCEP : n/a
Alternating Current, A: Unbalanced Wave: 10-60
Alternating Current, A: Balanced Wave : 20-30

Electrode Diameter:  1/16" (1.6mm)
Direct Current A: Straight Polarity | DCEN : 70-150
Direct Current A: Reverse Polarity | DCEP : 10-20
Alternating Current, A: Unbalanced Wave: 50-100
Alternating Current, A: Balanced Wave : 30-80

Electrode Diameter:  3/32" (2.4mm)
Direct Current A: Straight Polarity | DCEN : 150-250
Direct Current A: Reverse Polarity | DCEP : 15-30
Alternating Current, A: Unbalanced Wave: 100-160
Alternating Current, A: Balanced Wave :  60-130

Electrode Diameter:  1/8" (3.2mm)
Direct Current A: Straight Polarity | DCEN : 250-400
Direct Current A: Reverse Polarity | DCEP : 25-40
Alternating Current, A: Unbalanced Wave: 150-210
Alternating Current, A: Balanced Wave :  100-180

Electrode Diameter:  5/32" (4.0mm)
Direct Current A: Straight Polarity | DCEN : 400-500
Direct Current A: Reverse Polarity | DCEP :40-55
Alternating Current, A: Unbalanced Wave: 200-275
Alternating Current, A: Balanced Wave :  160-240

Electrode Diameter:  3/16" (4.8mm)
Direct Current A: Straight Polarity | DCEN : 500-750
Direct Current A: Reverse Polarity | DCEP : 55-80
Alternating Current, A: Unbalanced Wave: 250-350
Alternating Current, A: Balanced Wave :  190-300

Electrode Diameter:  1/4" (6.4mm)
Direct Current A: Straight Polarity | DCEN : 750-1100
Direct Current A: Reverse Polarity | DCEP : 80-125
Alternating Current, A: Unbalanced Wave: 325-450
Alternating Current, A: Balanced Wave : 325-450

Different electrode materials will vary slightly from these guidelines. Use of other gases will also change the recommended currents. Use this chart as a general guide. Also keep in mind that for a given amount of amperage, larger diameter electrodes will last longer but will be harder to start. Excessive current will cause the electrode to melt and drop off. Insufficient current will lead to an unstable arc.