What type of current is typically used in TIG welding?

TIG welding, or Tungsten Inert Gas welding, often employs both alternating current (AC) and direct current (DC) depending on the material being welded. Direct current is commonly used for welding ferrous metals like steel and stainless steel, as it provides a stable arc and heat control. Conversely, alternating current is primarily utilized for welding non-ferrous metals such as aluminum, which benefits from the cleaning action of AC to remove the oxide layer on the material’s surface. This versatility in using both types of current makes it possible to achieve optimal welding results across a wide variety of materials, which is why the answer encompasses both AC and DC options. Understanding this aspect of TIG welding is crucial for a welder, as it directly affects the quality and effectiveness of the weld based on the material composition.