What is the impact of very low current on the tungsten electrode?

Very low current during gas tungsten arc welding (GTAW) can lead to unstable welding conditions, particularly at the tungsten electrode's tip. When the current is insufficient, the heat generated is not enough to maintain a stable arc. As a result, the arc may wander erratically, causing difficulty in achieving a consistent and controlled weld. This erratic behavior can lead to uneven heating of the workpiece and challenges in welding quality.

In contrast, higher current levels tend to produce a more stable arc. The stability allows for better control over the weld pool and the heat input, which are crucial for achieving high-quality welds.

Understanding the relationship between current levels and arc stability is essential for successful GTAW applications, as it directly affects the welding process and the properties of the weld.