How To Choose The Right Tungsten Electrode
Apr 25, 2023
Choosing the right tungsten electrode can be challenging as a beginner in Tungsten Inert Gas (TIG) welding.The tungsten electrode is a critical component of the TIG welding process as it conducts the electric current to the welding arc and helps to produce a stable, consistent arc. Here are some tips on how to choose the right tungsten electrode as a beginner:
- Type of material being welded.
- Type of weld.
- Welding output (AC or DC)
- Material thickness.
- Amperage range.
- Type of welding power source, transformer/rectifier or inverter.
Next, I will introduce the use of tungsten electrodes and the types of tungsten electrodes in TIG WELDING, Finally, let everyone know how to choose the tungsten electrodes that suit you.
What Welding Processes Use Tungsten Electrodes?
Tungsten is a rare metallic element used for manufacturing gas tungsten arc welding (GTAW) electrodes. The GTAW 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.
Role Of Tungsten In TIG Welding？
Tungsten's high melting point(3410°C)allows it to conduct the welding current to form an arc.The arc melts the base metal.Tungsten's hardness allows it to withstand the high temperatures without rapidly eroding.However,tungsten can contaminate the weld pool,so a sharp point and high current levels are avoided.
tungsten's properties make it essential for GTAW:It can handle the high temperatures to form an arc,yet the arc and weld pool can be precisely controlled based on tungsten chemistry and geometry.Skilled welders know how to match these variables to the application.Tungsten is at the heart of the art of TIG welding.
Tungsten Color Coding: What’s the Deal?
Each type of tungsten electrode is clearly color-coded. The end of the electrode is colored and each color represents a type of electrode.You can use the picture below to understand what each color represents.
Blue Lanthanated Tungsten Electrodes
Lanthanated tungsten electrodes are made of at least 97.80% tungsten with the addition of 0.8-1.7% lanthanum oxide (La2O3), also known as lanthana. The added lanthana improves arc starting, stability and performance for both AC and DC welding. It also helps the electrodes maintain a sharp tip for welding steel as well as a rounded tip for welding aluminum alloys and non-ferrous metals during AC TIG welding.
Benefits of Blue Lanthanated Tungsten：
- High conductivity.
- Stable arc.
- Easy arc starting.
- Heat resistant.
Downsides of Blue Lanthanated Tungsten：
- Limited sizes.
- Higher contamination risk.
- Slightly radioactive
Green (Pure) TIG Welding Electrodes
Made of 99.5% pure tungsten, green TIG welding electrodes are most often used for welding magnesium or aluminum with alternating current (AC). Green welding electrodes can be found in virtually any welding shop.While inexpensive and affordable compared to other choices, green tungsten burns up at a much faster rate than other alloys. So if you plan to use green tungsten, it is best to have plenty on hand.
Benefits of Green Tungsten：
- Ideal when working with AC
- Ideal for wave welding
- Forms a clean balled tip, resulting in good arc stability
- Good for magnesium and aluminum welds
Downsides of Green Tungsten：
- Burns up quickly.
- Needs frequent replacement
- Weaker arc not ideal for DC welding
Red (Thoriated) TIG Welding Electrodes
Red thoriated tungsten electrodes contain 2% thorium oxide, which improves arc starts and allows higher current capacity. The lower melting point results in less consumption and longer life. Red tungsten works well for AC and DC welding of thin metals. However, thorium is radioactive, so safety precautions are needed. Thoriated electrodes are versatile and widely used.
The thorium oxide reduces the operating temperature, minimizing weld contamination and electrode consumption. Thoriated electrodes work well for DC welding carbon steel, stainless steel, nickel and titanium alloys. However, they perform poorly for AC welding and maintaining a balled end.
Benefits of Red Tungsten：
- Durable (low consumption rate)
- Easily establish and maintains a sharp edge
- Easy to work with (ideal for novices)
- Low weld puddle contamination
- Provide good arc starts
- Higher current-carrying capacity
- Can be used for both AC and DC welding
- Good for thin metals and alloys such as titanium, steel, aluminum, nickel and more
Downsides of Red Tungsten：
- Thorium is radioactive, posing an additional health hazard
- Poor AC welding
- Difficult to form and maintain a rounded tip
Grey (Ceriated) TIG Welding Electrodes
Grey ceriated tungsten electrodes contain 2% cerium oxide. They work well for low-amp DC and AC welding with impressive arc starts. Popular for small or thin parts, grey tungsten is good for titanium, nickel and steel. EWCe-2 is the major grade.Ceriated electrodes have 97.3% tungsten and 1.8-2.2% cerium oxide.
EWCe-2 provides good low-amp DC welds with better arc starts and less vaporization than green tungsten. Similar to thoriated,ceriated suit thin sheet, pipe and delicate welds. Ceriated excel in low-amp situations where thoriated struggle.
Benefits of Grey Tungsten：
- Excellent low-amp arc starts
- Good arc stability
- Preferred for delicate jobs
- Versatile applications
Downsides of Grey Tungsten：
- cannot handle high heat well due to greater electrode melt-off and decay
- High amps can change the composition of the electrode
Gold (Lanthanated) Tungsten Electrodes
Gold lanthanated tungsten electrodes contain 1.3-1.7% lanthanum oxide. They work with DC/AC and pointed/balled ends. Lanthanated tungsten offers excellent arc starts, slow decay, stability and re-ignition like ceriated.Gold tungsten handles DC/AC applications and suits stainless/steel welding.
They maintain sharp points for DC/AC square wave welding. The lanthanum oxide enables lower operating temperatures,minimizing contamination and consumption.Lanthanated tungsten provides quality welds for carbon steel,stainless steel and nickel alloys, especially useful for AC welding.
Choosing The Right Tungsten Electrode
Choosing the proper tungsten is crucial for quality welds. Each tungsten has pros and cons, but master them allows utlizing their advantages. Comprehending the traits of every tungsten and preparation methods helps deduce the right one for steels, stainless or aluminum! With the right tungsten, an exceptional arc and boosted weld performance come!
Though different tungstens suit different metals, understanding them from characteristics to preparation enables leveraging the most from each.The perfect tungsten partnered with the right technique paves the way for crackerjack welds of any metal.
Hopefully, our article helped you understand a small part of the complicated puzzle called TIG welding.
Come to our tungsten collection to choose the tungsten that suits you.