Thorium - tungsten electrodes are radioactive and have almost been phased out. Since the search for a replacement for the thorium tungsten electrode began, scientists have not stopped. Until the tungsten electrode variety has been many, especially the composite rare earth tungsten electrode breakthrough, there has been a great progress.

Let's start with the unit rare earth tungsten electrode, which was first developed in the 1980s. Will be rare earth oxide La2O3, Y2O3, CeO2, adding to the tungsten oxide, respectively after reduction, sintering and processing preparation was the clock specifications of the tungsten electrode, after the arc properties of the electrode material, electric arc static characteristic, burning resistance and welding procedure test found that three kinds of rare earth Wu Dianji has good welding performance, welding performance is better than that of the same specification of thorium-tungsten electrode materials. However, only limited to small current welding, large current burning loss, poor stability of electron emission.

By the end of the 1990s, researchers had explored the limitations of the unit compound rare earth tungsten electrode and developed nine binary compound rare earth tungsten electrodes. It is found that the performance is better than the composite tungsten electrode. However, the existing problem is the low processing rate, which restricts the industrialization of production.

Nowadays, with the progress of science and technology and modern industry, the welding performance of tungsten electrode is required to be higher, so the ternary composite tungsten electrode comes into being. There are three rare earth elements compound processing. Through the characterization of its arc initiation characteristics, arc static characteristics and burn resistance properties, it is found that the welding performance is better than thorium tungsten electrode. Now it is a kind of more ideal environmental protection product, but also faces the problem of low rate of processed air accidents. Further improvements are needed in the future.