Mode for wire drawing electrode material of multielement composite rare earth tungsten

Abstract

A draw method for preparing the multi-element composite RE-W electrode material includes such steps as preheating the drawing dies to 500-550 deg.C, raising the furnace temp to 1175-1225 deg.C, making the heating power constant, sequentially drawing with the pre-heated phi 2.5, phi 2.0, phi 1.6 and phi 1.2 dies, regulating the heating powder of furnace to make the furnace temp be 875-925 deg.C, and drawing with phi 1.1 die.

Description

Technical field: [0001] The invention relates to an industrial wire drawing method for a multi-element compound rare earth tungsten electrode material, which belongs to the technical field of rare earth refractory metal functional material processing. Background technique: [0002] Thorium tungsten electrodes are widely used in welding, thermal spraying, thermal cutting, and special light sources as electron sources and ion sources. Since thorium is naturally radioactive, its production and use will pollute the environment and endanger human health. New electrode materials have become a research hotspot for scientific researchers. Rare earth oxides have low work function, so they have attracted much attention. Studies have shown that doping a small amount of rare earth metal oxides in tungsten can significantly reduce the surface work function of the material and promote electron emission. Lanthanum tungsten electrodes, cerium tungsten electrodes, and yttrium tungsten electr...

AI Technical Summary

Problems solved by technology

Rare earth oxides have low work function, so they have attracted much attention. Studies have shown that doping a small amount of rare earth metal oxides in tungsten can significantly reduce the surface work function of the material and promote electron emission. Lanthanum tungsten electrodes, cerium tungsten electrodes, and yttrium tungsten electrodes Rare earth tungsten electrodes and other units have been successfully developed and introduced to the market. However, the above electrode materials have their own advantages and disadvantages: the lanthanum tungsten electrode has good arc stability and electrode burning resistance when working at medium and small currents, but its processing performance is poor. , Serious burning loss when using high current; cerium tungsten electrode has excellent arc ignition performance, but it can only be used in the case of small current welding, and serious burning loss under high current load; Yttrium tungsten electrode has high arc pressure when used. The electrode has good anti-burning performance when working with high current, but its processing is difficult, and the arc stability is poor when used at low current; therefore, it cannot completely replace the radioactively polluted thoriated tungsten electrode

[0003] On the basis of the unit rare earth tungsten electrode research, multi-element composite rare earth tungsten electrode materials have been developed successively. This type of material is added with a variety of rare earth oxides. Therefore, the welding performance of the multi-element composite rare earth tungsten electrode is better than that of the thoriated tungsten electrode of the same specification. However, the rare earth seriously changes the mechanical properties of the tungsten matrix while promoting electron emission. The second rare earth relative to the tungsten grain boundary The hindering effect makes the processing performance of the rare earth tungsten electrode very poor, especially for the wire drawing process, the product yield is very low, about 60%, and the high production cost has led to the fact that no multi-element composite rare earth tungsten electrode has been introduced to the market, hindering the replacement The process of thoriated tungsten electrodes