What does E W T h-1 or 2 signify in tungsten electrodes?

The designation E W T h-1 or 2 indicates that the tungsten electrode contains 1-2% thorium. Thorium is added to tungsten to improve its arc stability, increase its operating temperature, and enhance its electron emission properties. This makes thorium alloyed electrodes particularly effective in AC and DC welding processes, providing a reliable and consistent performance. The addition of thorium allows the electrode to maintain a stable arc and improve overall weld quality, making it a popular choice among welders for critical applications.

Recognizing the significance of each element is essential, as using incorrect material can lead to suboptimal performance or safety issues. For example, tungsten electrodes alloyed with silver or copper would not provide the same benefits as those with thorium, and aluminum additives are not relevant in the context of tungsten electrode composition for GTAW, as they do not enhance the electrode's electrical and thermal characteristics in the same way.