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Author(s): |
Jin-shu Wang, The Key Laboratory of Advanced Function Materials, Ministry of Education, School of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
Yun-tao Cui, The Key Laboratory of Advanced Function Materials, Ministry of Education, School of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
Wei Liu, The Key Laboratory of Advanced Function Materials, Ministry of Education, School of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
Xi-zhu Zhang, The Key Laboratory of Advanced Function Materials, Ministry of Education, School of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
Yi-man Wang, The Key Laboratory of Advanced Function Materials, Ministry of Education, School of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
Mei-ling Zhou, The Key Laboratory of Advanced Function Materials, Ministry of Education, School of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China |
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Abstract: |
Scandia doped tungsten pressed cathodes were prepared, including mixing scandium oxide and barium-calcium aluminates with tungsten by different powder mixing methods combined with high temperature sintering under the protection of hydrogen. Experimental results show that mixing uniformity plays important roles in the cathode emission. The powders prepared by ball-milling have small particle size and uniform distribution of different elements. This kind of powder is favorable for the chemical reaction between emission salt and tungsten to take place fully to form active substance which could improve the emission property. The emission current density of the cathode prepared with ball-milling powders is about eight times higher than that prepared with hand mixing, at the same time, four times higher than M-type cathode.During the activation of cathode, the surface active layer containing Ba, Sc and O is established due to the simultaneous diffusion of Ba, Sc and O, leading to the improvement of emission property.
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