The yttrium tungsten electrode is a composite electrode made from tungsten and yttrium, created by adding an appropriate amount of yttrium oxide (Y?O?) as a modifier to a pure tungsten electrode. Its English name is yttrium tungsten electrode, with a common grade of WY20, a blue color-coded tip, diameters ranging from 0.5mm to 12.0mm, and lengths typically of 150mm or 175mm.
The yttrium tungsten electrode combines the traits of pure tungsten electrodes and yttrium oxide, featuring a high melting point, high elastic modulus, strong electron emission, excellent arc initiation, high arc column stability, low burn rate, good electrical and thermal conductivity, as well as corrosion and oxidation resistance. Notably, doping pure tungsten electrodes with yttrium oxide— which has a lower electron work function—raises the recrystallization temperature and enhances electron emission, addressing the low emission efficiency and fragility of pure tungsten electrodes.
The production of yttrium tungsten electrodes involves: first, uniformly mixing a yttrium nitrate solution into ammonium paratungstate or tungsten trioxide via spray doping; then heating and drying to form yttrium-tungsten coated powder; followed by two reduction steps to produce yttrium-tungsten powder; pressing and high-temperature sintering the powder into yttrium-tungsten billets; and finally forging the billets into the final product.
Yttrium tungsten electrodes are primarily used for welding military and aerospace components, commonly applied to materials such as carbon steel, stainless steel, and copper-aluminum alloys.
Besides yttrium oxide, pure tungsten electrodes can be modified with cerium oxide, thorium oxide, lanthanum oxide, or zirconium oxide. The varying additives result in slight differences in the performance and applications of the resulting tungsten electrodes.
