GTAW Advanced Welding Practice Exam

In GTAW the tungsten electrode is non-consumable: it provides the arc heat but stays intact, while any filler metal is added separately with a filler rod. Tungsten has a very high melting point, so it doesn’t melt into the weld pool or dissolve into the weld; the electrode tip may wear a bit from erosion, but it isn’t consumed as part of the weld metal. The shielding gas protects the weld from atmospheric oxygen, so the electrode isn’t consumed by oxygen.