What characteristic does high frequency current add to alternating current (AC) in GTAW?

High frequency current enhances the stability and consistency of the arc during Gas Tungsten Arc Welding (GTAW). When high frequency is applied to alternating current (AC), it generates an ionized pathway that helps to maintain the arc even when the welding torch is lifted slightly away from the workpiece. This is particularly useful for preventing arc instability, allowing the welder to execute more controlled movements without losing the arc.

Having a stable arc is critical for achieving consistent weld quality, especially in the context of thin materials where precise control over heat input is required. This stability also aids in initiating the arc more easily, which can be particularly beneficial in welding processes that involve reactive materials. Thus, the addition of high frequency current effectively ensures that the arc remains intact, contributing to better control and overall welding performance.