Transactions of Nonferrous Metals Society of China
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|Vol. 12 No. 2 April 2002|
tungsten cathode by swaging technique
（School of Materials Science and Engineering，
Xi′an Jiaotong University, Xi′an 710049, China）
Abstract:By using the high energy ball milling method, the nanosized ThO2 powders were obtained. Through mixing powders, sintering and hot swaging processing, a nanocomposite thoriated tungsten cathode was fabricated. The relative density of the nanocomposite material is near 100%. The microstructure of nanocomposite cathode is quite different from that of conventional thoriated tungsten cathode. Most of thoria particles are less than 100nm in diameter, and distribute on t he boundaries of tungsten grains. The nanocomposite cathode shows a much lower arc starting field than that of conventional cathode, which will improve the performance of the cathode significantly.
Key words: W-ThO2 cathode; nanosized powders; nanocomposite; swaging