Which tungsten electrode designation corresponds to 2% Cerium Tungsten?

• A. EWCe-2 (2% Cerium Tungsten)
• B. EWTh-1
• C. EWZr
• D. EWLa-1

Answer: (A)

Tungsten electrode designations are built to show the dopant and its percent content. The prefix EW identifies a tungsten electrode, the letters that follow indicate the dopant material, and the number after the dash shows the percent oxide used. Cerium-doped tungsten uses Ce as the dopant, with the dash number giving the percent of cerium oxide.

So a designation that includes Ce and the number 2 specifically means 2% cerium oxide in the tungsten. That is why EWCe-2 is the correct match for 2% Cerium Tungsten. This type of electrode is chosen for its arc starting and stability characteristics, and it avoids the radioactivity concerns associated with thorium-doped electrodes. The other options reflect different dopants—thorium, zirconium, or lanthanum—so they do not represent 2% cerium tungsten.