How do you recognise a good tungsten electrode?

Anyone who welds high-quality metals and wants clean and visually appealing weld seams should use a TIG welding torch. In TIG welding, non-melting tungsten electrodes – also called TIG electrodes – are used. A tungsten electrode can be called an absolutely essential part of a TIG welding torch, because it has a significant influence on the success of a weld seam as required.

The main component of every TIG electrode is tungsten. Apart from the green tungsten electrode (WP), which consists of pure tungsten, the other TIG electrodes available on the market have other elements such as zirconium oxide, lanthanum oxide, yttrium oxide, cerium oxide or thorium oxide. These are also called dopings. Depending on the doping, the tungsten electrodes have different properties with regard to their ignition and re-ignition behaviour, their arc stability and their service lives.

The following 3 criteria characterise a good tungsten electrode

1. Good and reproducible ignition behaviour

A poorly igniting tungsten electrode is not only annoying, but also says a lot about its further performance, which can then in turn negatively affect the welding process. For example, the tungsten electrode containing cerium oxide (WCe) has very good ignition properties. The TIG electrode with lanthanum oxide (WLa) and the one with zirconium oxide (WZr) also score with good ignition properties. However, one thing has to be considered for tungsten electrodes with only one doping additive: the longer a tungsten electrode is in use, the more doping elements evaporate in the course of the processes. This also means that it is more difficult to ignite, but also that the arc becomes more unstable. A closer look at the electrode tip will show it: If it is porous or open-pored – an indication of evaporated components – the tungsten electrode should be replaced with a new one.

2. Stable arc

A flickering, i. e. unstable arc cannot produce an optically good-looking weld seam. Those who cannot do without a stable arc due to their welding task should use the pure tungsten electrode (WP). Thorium oxide as a doping element also ensures a stable arc, but thoriated electrodes are now banned in many countries due to their radioactivity. Even the storage of tungsten electrodes with thorium oxide is highly harmful to health due to their radiation exposure. We expressly do not recommend TIG electrodes with this doping element.

3. Service life of the electrode

Rapidly emitting oxides, too high loads and thus high temperatures inside the electrode lead to a shortened service life of a tungsten electrode. Of course, every doped TIG electrode loses its doping elements over time through evaporation. Tungsten electrodes with several doping elements consistently have longer service lives. You can also read more about this in the blog "Practical tips for welding: tungsten electrodes".

Whether a tungsten electrode fulfils the three criteria mentioned above is influenced by:

• the manufacturing process itself
• the material composition

Therefore, when purchasing tungsten electrodes, pay attention to a quality product from a renowned manufacturer. The E3^® tungsten electrode from ABICOR BINZEL is a TIG electrode that fulfils all three criteria – good ignition behaviour, stable arc and long service life. No other tungsten electrode, which is currently available on the market, has the same capability. The E3^® consists of a mixture of rare earth oxides and is also popular for automated processes because of its extremely high reliability.

Please also have a look at this video:

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