| 摘要 |
PURPOSE:To obtain a cathode body with suitable electron emission characteristics by applying heat treatment under hydrogen atmospheres before metal ultra- fine powder is mixed in alkaline earth carbonate powder. CONSTITUTION:Before the metal ultra-fine powder whose particle diameter is less than 0.3mu is mixed in alkaline earth carbonate powder, it is heat-treated under hydrogen atmospheres. For example, the nickel powder 3 whose average particle diameter is 300Angstrom is heat-treated for five minutes at 450-850 deg.C under the hydrogen atmospheres and this powder is mixed in the alkaline earth carbonate 2 at a weight ratio of 10%. Then a nitrocellulose solution and butyl acetate are mixed in this mixing substance and a suspension or paste is obtained and then substrate metal 1 is coated with the suspension or paste. It is suitable that the coating thickness is 60-100mu when the diameter of the substrate metal 1 is 2mm.. As a result, a cathode body with high electron emission characteristics can be obtained. |
