In which welding process is an inert gas used to shield the arc and weld pool?

The use of an inert gas to shield the arc and weld pool is a defining characteristic of TIG welding. This process employs a non-consumable tungsten electrode to produce the weld, and an inert gas, commonly argon or helium, is used to protect the weld area from atmospheric contamination. This shielding prevents oxidation and other reactions that can affect the quality of the weld, ensuring a clean and high-integrity weld.

In contrast, other welding methods may use different shielding techniques or materials. For instance, MIG welding also uses a gas shield, but it employs a consumable wire electrode instead of a non-consumable tungsten electrode. Stick welding uses a flux-coated electrode that produces shielding gas during the welding process, whereas flux-cored welding uses a tubular wire filled with a flux material that generates shielding gas during the process as well, but does not rely on an inert gas like argon or helium in its fundamental operation.

Thus, the unique aspect of TIG welding lies in its exclusive use of inert gases to create a protective atmosphere that enhances the welding process, making it suitable for applications requiring precision and a clean finish.