Cerium Tungsten Electrodes of The Electrode Performance

China started to develop in the 1970s, cerium tungsten electrode material , after nearly 10 years of production practice , the production process tends to be stable and mature , in the early 1980s , the country and internationally cerium tungsten electrode material for the production of patents. In the production process , how to make a tungsten doped ceria -based in vivo distribution and dispersion , the electrode is to improve the electron emission capability , improved arc performance , extend the life of one of the important factors . Therefore, the choice of raw materials , usually by blue tungsten oxide or doped tungsten oxide , and the doping agent is not used directly cerium oxide , instead of using the soluble salts such as cerium chloride or cerium nitrate . This aqueous solution as the mother liquor , add inwards blue tungsten trioxide or tungsten , during the addition , the heating and stirring continuously , and concentrated by evaporation to form a coating powder. Doping can also be an aqueous solution of cerium nitrate, cerium chloride or spray containing tungsten blue oxide powder, tungsten or a special container ( heat while rotating ) . The powder doped must be heated to a certain temperature , the salts decompose to form cerium oxide particles distributed in the tungsten trioxide powder, tungsten or blue on the surface of the particles , and then after hydrogen reduction , to obtain W-CeO2 powder. CeO2 content of 1% to 4%, selected according to requirements . Doped powder after molding, burn , vertical melt , get cerium tungsten billet , see doped tungsten its production process , but its swaged temperature slightly higher for 1500 ~ 1600 ℃.

As the electrode material , the level of electron work function is the amount of material raft electron emission performance is an important indicator of good or bad . Only a low electron work function , in order to meet the arc stability, focus , load current density process performance requirements. Experiments show that cerium tungsten electrodes with thorium tungsten electrode is lower than the electron work function ( pure tungsten electron work function of 4.55eV, W-2% ThO2 is 2.7eV, W-2% CeO2 is 2.4eV ) , this electrode material than thoriated tungsten electrode has greater advantages . First , cerium tungsten electrodes electron emission capability , easy to get a slim arc , so that the heat is more concentrated , the allowable current density thoriated tungsten electrodes increased by 5 % to 8% . Secondly , cerium tungsten electrodes burning rate, long life , easy to arc initiation and stability are guaranteed . Again , cerium tungsten electrodes radioactive dose is very low, and only about one thousandth of thorium tungsten materials , the equivalent radiation dose earth soil . So instead of using cerium tungsten electrodes thorium tungsten electrode , not only can eliminate the production and use of human cumulative internal radiation hazards, and eliminating radioactive contamination of the environment , but also in technical performance and the results are also able to replace thoriated tungsten electrodes , Some properties even superior than thorium tungsten material .


Tungsten Alloy Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-alloy.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com;sales@xiamentungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn

 

• < Prev
• Next >