What happens if the tungsten electrode touches the workpiece?

When the tungsten electrode touches the workpiece during Gas Tungsten Arc Welding (GTAW), it can lead to contamination. This is primarily because the tungsten electrode is made of a specific material that can pick up impurities from the surface of the workpiece upon contact. These impurities can then be transferred into the weld pool, compromising the integrity of the weld.

The introduction of contaminants into the weld can lead to defects such as porosity or lack of fusion, which can weaken the overall strength of the weld joint. In addition, when the tungsten is contaminated, its ability to maintain a stable arc is diminished, which can affect the quality of the welding process. Thus, ensuring that the electrode does not make contact with the workpiece is critical to maintaining a clean and effective welding operation.