Fabrication and thermionic emission properties of lanthanum carbide doped tungsten cathodes

被引：7

作者：

Dong, Liran ^{[1
]}

Wang, Jinshu ^{[1
]}

Liu, Wei ^{[1
]}

Li, Changcai ^{[1
]}

Zhang, Jie ^{[1
]}

Yang, Yunfei ^{[1
]}

Zhou, Fan ^{[1
]}

机构：

[1] Beijng Univ Technol, Coll Mat Sci & Engn, Key Lab Adv Funct Mat, Beijing 100124, Peoples R China

来源：

MATERIALS LETTERS | 2015年 / 146卷

基金：

中国国家自然科学基金;

关键词：

Electronic materials; Powder technology; Metals and alloys; Lanthanum carbide; FIBER;

D O I：

10.1016/j.matlet.2014.11.154

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

A new type of thermionic cathode, lanthanum carbide doped tungsten cathode, has been fabricated through a spark plasma sintering method by using the mixed powders of lanthanum carbide and tungsten. Lanthanum carbide powder was prepared by a levitation melting method in vacuum. The thermionic emission properties have been investigated. It is found that the concentration of lanthanum carbide has a significant influence on the emission properties of the cathodes. The emission current density of the tungsten cathode at 1400 degrees C-b was increased dramatically from 1.09 to 3.12 A/cm(2) with the increase of concentration of lanthanum carbide from 3.5 to 10 wt%. The emission mechanism of the cathode has been discussed. (C) 2014 Elsevier B.V. All rights reserved.

引用

页码：47 / 50

页数：4

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