In GTAW (TIG) welding, which tungsten electrode type is commonly used for DC welding?

In GTAW (TIG) welding, which tungsten electrode type is commonly used for DC welding?

• A. Pure Tungsten
• B. 2% Thoriated Tungsten (or 2% Lanthanated as an alternative)
• C. 2% Zirconated Tungsten
• D. Copper Tungsten

Answer: (B)

In GTAW, you want a tungsten with good electron emission and arc stability for direct current. Doped tungsten with oxide additives provides that, making the arc easier to strike and more stable as you run DC welds. Specifically, 2% thoriated tungsten has thorium oxide that enhances electron emission and current-carrying capacity, so it holds a steady DC arc for various metals like steel and stainless. A popular non-radioactive alternative is 2% lanthanated tungsten, which behaves similarly in DC welding and is widely used for its reliability and longer life. Pure tungsten lacks the oxide dopants, so it doesn’t emit electrons as readily and can result in a harsher, less stable DC arc. Zirconated tungsten is often favored for AC welding and high-frequency starts, while copper-tungsten is a specialized composite more suited to other tasks, not typical TIG electrodes for DC welding.

In GTAW, you want a tungsten with good electron emission and arc stability for direct current. Doped tungsten with oxide additives provides that, making the arc easier to strike and more stable as you run DC welds. Specifically, 2% thoriated tungsten has thorium oxide that enhances electron emission and current-carrying capacity, so it holds a steady DC arc for various metals like steel and stainless. A popular non-radioactive alternative is 2% lanthanated tungsten, which behaves similarly in DC welding and is widely used for its reliability and longer life. Pure tungsten lacks the oxide dopants, so it doesn’t emit electrons as readily and can result in a harsher, less stable DC arc. Zirconated tungsten is often favored for AC welding and high-frequency starts, while copper-tungsten is a specialized composite more suited to other tasks, not typical TIG electrodes for DC welding.