Abstract:Three types of tungsten electrodes containing three rare earth oxides, namely Y₂O₃, La₂O₃, and CeO₂ and one with Y₂O₃ and CeO₂were prepared, in which the total contents of rare earth oxides are 2.2% in mass, and the characteristics of these electrode materials were studied. By TIG welding, the welding characteristics including arc starting, arc static properties and electrode consumption of these electrodes were also analyzed. The results suggest that the electrodes added three rare earth oxides are more favorable for processing than that added two rare earth oxides. All the electrodes activated with two or more rare earth oxides are more superior to W-ThO2in operating, and the electrode combined with Y₂O₃ and CeO₂shows the best properties when it is used at a heavy current for a long time. The analyses of the results of electrode consumption indicates that the rim forming during arcing is one of the important reasons for electrode’s heavy erosion, and the increased Y₂O₃ content in electrodes is beneficial to retard the formation of rim, and leads to the improvement of consumption resistance of the electrodes.

Key words: rare earth oxides　tungsten electrode　welding　rim　 Y₂O₃+La₂O₃+CeO₂