中國有色金屬學(xué)報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 11 No. 1 February 2001 |
YAO Cao-gen(姚草根), NIE Zuo-ren(聶祚仁), ZUO Tie-yong(左鐵鏞)
（School of Materials Science and Engineering, Beijing Polytechnic University,
Beijing 100022, P.R.China）
Abstract:The ion implanting method has been taken for implanting lanthanum ions into the surface layer of molybdenum wires in order to study the function of carbide layer on the surface of La2O3-Mo cathode in the emission. The function mechanism has been discussed by using XPS and AES methods. The results show that the carbide layer mainly acts as a reduction reagent to produce metallic lanthanum. Moreover, it can store the activator substance and carry them to the surface. Based on the research results, the carbonization technique has been changed. By applying the new technique, the lifetime of the La2O3-Mo cathode has been improved from 14 h to more than 1 000 h—the minimum lifetime for practical uses.
Key words: carbide layer; La2O3-Mo cathode; reduction; lifetime
