lanthanum oxide, zirconium oxide, yttrium oxide and thorium.

tungsten carbide inserts needle main purposes: for the production of high intensity gas discharge lamp arc tubes electrode.Because the characteristics of tungsten, makes it very suitable for soldering and other similar tiG electrode material such work. In adding rare earth oxides of tungsten to stimulate its electronic work function, making the tungsten electrode welding performance can be improved: electrode arc better performance, higher stability of the arc column electrode burning rate is smaller. Usual additives earth cerium oxide, lanthanum oxide, zirconium oxide, yttrium oxide and thorium.Tungsten needle for TIG welding, which is a tungsten matrix by powder metallurgy method of incorporation of about 0.3% -5% of a rare earth element such as: cerium, thorium, lanthanum, zirconium, yttrium and the production of tungsten alloy bar, then through pressure processing, diameters from 0.25 to 6.4mm, standard lengths from 75 to 600, while the most commonly used specifications for diameter 1.0,1.6,2.4 and 3.2, the shape of the TIG electrode terminal is a critical factor when Use DCSP, the electric extreme need to grind the tip shape, and with its tip angle range of applications, electrode diameter and welding current to change, narrow joints need a smaller tip angle when welding very thin materials, the need to low current, needle-like electrodes for a minimum to stabilize the arc, and to ensure proper grounding electrode arc easily, good arc stability and appropriate weld bead width. When the AC power to the welding, grinding electricity without the extreme, because using the appropriate welding current, electrode terminals will form half of the ball, if the increase in the welding current, electrode tip becomes bulb-shaped and may melt and contaminate molten gold.Tungsten high melting point (3683 ℃ ± 20 ℃), the electron emission capability, high modulus, low vapor pressure, so it has long been used as a thermal electron emission material [. Pure tungsten electrode emission efficiency is low and at high temperatures the formation of equiaxed recrystallized grains leaving the filament sag, break. To overcome these shortcomings, to adapt to modern industrial new technologies, new technology development, national materials workers are committed to research and development of new electrode materials. Some doped tungsten-based low electron work function of rare earth oxides, both to improve the recrystallization temperature, but also activate the electron emission. Rare earth metal oxide has excellent thermal electron emission capability, rare earth tungsten electrode material has been an alternative to conventional radioactive thoriated tungsten electrode material development direction. This article describes several rare earth tungsten electrode material preparation and research, as well as the electrode material on the application of the situation and prospects of the tungsten electrode potential applications, designed for China's rare earth tungsten electrode materials research and application of reference.

Tungsten needle in the arc in TIG arc starting, arc stability and weld quality have played an important role. In the arc occurs under high temperature loss of quality tungsten electrodes, tungsten electrodes called ablation. To facilitate discussion of the tungsten electrode ablation mechanism, ablation can be divided into ablative and tungsten oxide added ablation itself.