EWCe-2 (2% Ceriated) electrodes are tungsten electrodes containing about 2% cerium oxide, referred to as ceria.  The EWCe-2 electrodes were first introduced into the US market in 1987.  Several other grades of this type of electrode are commercially practical, including electrodes containing 1% ceria, but only one grade, EWCe-2, has been incorporated in this specification as having commercial significance.  The advantages of tungsten electrodes containing ceria, compared to pure tungsten, include increased ease of starting, improved arc stability, and reduced rate of vaporization or burn-off.  Unlike thoria, ceria is not a radioactive material.  These advantages increase with increased ceria content.  These electrodes operate successfully with AC or DC, either polarity.

Chemical Composition Requirements

AWS A5.12M/A5.12:2009