Thoriated tungsten electrodes, were designed for direct current electrode negative (DCEN) or straight polarity applications.

They maintain a sharpened tip configuration during welding which is desirable for the welding of steels, nickel alloys, and most alloys other than aluminum and magnesium.

Thoriated tungsten electrodes are not normally used with AC welding because it is difficult to maintain the balled end (which is necessary with AC welding) without splitting the electrode.