| 摘要 |
PURPOSE:To obtain a cathode with high current density by mixing one or more kinds of metal carbide of IIa, III, IVb, VIa, VIIa and VIII groups into an alkaline earth metal oxide layer so as to increase the conductivity of the oxide layer. CONSTITUTION:An electron radiating material 2 mixed with one or more kinds of metal carbide of IIa, III, IVb, VIa, VIIa, and VIII groups in the periodic table into alkaline earth metal oxide containing Ba is deposited on a metal substrate 1 mainly composed of Ni. For example, 1.0wt% of silicon carbide is added to ternary carbonate of Ba, Sr, Ca, then nitrocellulose lacquer and butyl acetate is added to it and mixed to form a suspension, which is coated by spraying on an Ni substrate containing a reducing element such as Si, Mg at a thickness of about 100mum. Powder of Mg2C, LaC2, WC, MnC, Fe3C, etc. may be used in place of SiC powder. |
