| 摘要 |
<p>The cathode is mushroom-shaped and consists of a tube closed at one end by an emission layer support, while the other, open end is mounted through a holder on an insulating supporting disc. The heater is inserted into the open end of the tube. The cathode tube and the emission layer support are made in one piece (1), by a metal drawing operation. They are made of nickel with an addition of a total of at least 10 wt. % of one or several of the elements iridium, molybdenum, rhenium, rhodium, tantalum, zirconium, tungsten or platinum.</p> |
