During GTAW with DCEN, which describes the heat distribution between the electrode and the workpiece?

During GTAW with DCEN, which describes the heat distribution between the electrode and the workpiece?

• A. 30% heat at the electrode, 70% at the work
• B. 70% heat at the electrode, 30% at the work
• C. 50% heat at each
• D. 100% heat at the electrode

Answer: (A)

In GTAW, polarity controls where most of the arc heat goes. With the electrode as the negative (DCEN), current flows from the electrode to the workpiece, so the arc delivers most of its heat to the workpiece and the electrode acts more like a heat sink. That means roughly 70% of the heat ends up in the workpiece and about 30% in the electrode. The option describing 30% at the electrode and 70% at the workpiece matches this distribution. For contrast, using DC electrode positive (DCEP) reverses the split, with the electrode getting most of the heat, and alternating current tends toward a more even, about-50/50 distribution.

In GTAW, polarity controls where most of the arc heat goes. With the electrode as the negative (DCEN), current flows from the electrode to the workpiece, so the arc delivers most of its heat to the workpiece and the electrode acts more like a heat sink. That means roughly 70% of the heat ends up in the workpiece and about 30% in the electrode. The option describing 30% at the electrode and 70% at the workpiece matches this distribution. For contrast, using DC electrode positive (DCEP) reverses the split, with the electrode getting most of the heat, and alternating current tends toward a more even, about-50/50 distribution.