| 摘要 |
<p>PURPOSE:To obtain an economical quick action type impregnated cathode whose manufacturing is easy by applying high melting point metal powder to at least a part of the periphery of a high melting metal wire and impregnating the gap part of the high melting point metal powder with an electron radiant material. CONSTITUTION:For example, the spiral coil 6 of a tungusten wire of 0.1mm. in diameter is formed as a heater wire and high melting point metal powder 7 is electrodeposited on the periphery of the spiral coil 6 by means of such an electrodeposition device that is shown in the figure. When electrodeposition liquid 8 is agitated fully and a power supply 12, is applied to said coil with its magative potential impressed on the heater wire 6 the tungusten powder in the electrodeposition liquid 8 is attracted to the heater wire 6 side and adheres to the periphery of the heater wire. When the layer of the tungusten powder 7 reaches the desired thickness, the electrodeposition of the tungsten powder should be stopped. Then the tungusten powder 7 adheres to the periphery of the heater wire 6 and a porous layer is generated by heating it approximately at 2,000 deg.C under the hydrogen or vacuum atmosphere, and welding it. Then the periphery of this porous layer is coated with an impregnant combined by an electron radiant material.</p> |
