Which statement is true about Direct Current Electrode Positive (DCEP) in GTAW?

• A. With DCEP, the arc is formed at the electrode tip only
• B. With DCEP, the point of the electrode tip is stable
• C. DCEP has the highest heat concentration on the electrode tip
• D. DCEP produces the least heat at the tip

Answer: (C)

With Direct Current Electrode Positive, the electrode is the positive terminal and the workpiece is the negative terminal. In this arrangement, the electrode tip experiences intense ion bombardment, heating the tip more than other areas. The arc is established between the tungsten tip and the workpiece, but the polarity causes the hottest region to be at the electrode tip, so the heat concentration is greatest there. This is why the statement describing the electrode tip as the location of the highest heat concentration is true. The arc is not formed exclusively at the tip, the tip isn’t inherently stable under this polarity, and DCEP does not produce the least heat at the tip.