What is the primary function of AC frequency control in aluminum welding?

The primary function of AC frequency control in aluminum welding is to control the cleaning action of the arc. When welding aluminum, the oxide layer that forms on the surface can interfere with the welding process. By adjusting the AC frequency, welders can influence the balance between the cleaning and heating phases of the welding arc.

Higher AC frequencies allow for a more concentrated arc, which helps remove the oxide layer more effectively due to the increased cleaning action, resulting in a cleaner weld. This adjustment does not affect the heat input directly but modifies how the arc interacts with the material surface, allowing for better penetration and improved weld quality.

Understanding this key aspect of AC frequency control is crucial for achieving optimal welding results in aluminum, as it directly impacts the ability to produce strong and defect-free welds by addressing the challenges posed by surface contaminants.