Sintering behavior and DC emission properties of tungsten-rhenium mixed matrix dispenser cathodes

Author

Fan Zhou ; Chen Lai ; Xi Wang ; Wei Liu ; Jinshu Wang

Author_Institution

Sch. of Mater. Sci. & Eng., Beijing Univ. of Technol., Beijing, China

fYear

2015

fDate

27-29 April 2015

Firstpage

1

Lastpage

2

Abstract

Tungsten-rhenium mixed powders were prepared by a spray drying method followed by two-step reduction process. The reduction process and sintering behavior of the W-Re powders and the DC emission properties of the W-Re mixed matrix dispenser cathodes have been studied. Porous microstructure for the W-Re mixed powders was developed during the hydrogen reduction process. With the increase of the rhenium content in the W-Re powders, the grain size of the matrix decreased dramatically and the sintering temperature has to be increased correspondingly in order to obtain appropriate apparent porosity. W-75at%Re mixed matrix cathode demonstrates the highest electron emission among the W-Re mixed cathodes studied, with direct current density reaching 10.73 A/cm² at a temperature of 1000 °C.

Keywords

cathodes; current density; drying; electron field emission; hydrogen; porous materials; powder technology; rhenium alloys; sintering; spraying; tungsten alloys; vacuum microelectronics; DC emission properties; H₂; WRe; current density; electron emission; hydrogen reduction process; porous microstructure; sintering behavior; sintering temperature; spray drying method; temperature 1000 degC; tungsten-rhenium mixed matrix dispenser cathodes; tungsten-rhenium mixed powders; two-step reduction process; Compounds; Q measurement; Tungsten; W-Re matrix; dispenser cathode; microstructure; thermionic emission;

fLanguage

English

Publisher

ieee

Conference_Titel

Vacuum Electronics Conference (IVEC), 2015 IEEE International

Conference_Location

Beijing

Print_ISBN

978-1-4799-7109-1

Type

conf

DOI

10.1109/IVEC.2015.7223912

Filename

7223912