What is a notable outcome of using alternating current in welding thin gauge metals?

Using alternating current (AC) in welding thin gauge metals effectively reduces surface contaminants, which is particularly important in processes like Gas Tungsten Arc Welding (GTAW). When AC is employed, the polarity alternates between positive and negative, which helps in cleaning the surface of the base metal. The positive half of the AC cycle allows the welding arc to act as a cleaning action. It oxidizes surface impurities and oxides, lifting them away from the weld pool. This cleansing effect is crucial when working with materials such as aluminum or other non-ferrous metals, which can have a significant amount of surface contaminants that may lead to poor weld quality if not properly addressed.

AC also allows for better heat control when welding thin materials, helping to minimize warping and distortion, but the primary benefit related to contaminants is more pronounced. Thus, the notable outcome of using alternating current in welding thin gauge metals is the reduction of surface contaminants, which promotes stronger and cleaner welds.