| 摘要 |
Electron emission materials consisting of carbides, borides, and oxides, and related mixtures and compounds, of Group IVB metals Hf, Zr, and Ti, Group IIA metals Be, Mg, Ca, Sr, and Ba, and Group IIIB metals Sc, Y and lanthanides La through Lu are used in electrodes. These electron emission materials are typically contained in a refractory metal matrix formed of tungsten, tantalum, rhenium, and their alloys, but may also be used by themselves. These materials and electrodes have high melting points, low vapor pressures, low work functions, high electrical and thermal conductivity, and high thermionic electron emission and field emission properties.
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