| 摘要 |
<p>PURPOSE:To prevent the dispersion of the reduction ratio of the heat transfer coefficient by providing a nickel layer of 0.5-10mum on the back face of a cathode in contact with the filler metal powder. CONSTITUTION:Heaters 3 are buried by a filler material 4 and arranged to heat an emitter section 1. Molybdenum powder of 1-10mum and nickel powder of 0.1-1mum, for example, are used for the filler material 4. A tungsten wire coated with alumina is used for the heaters 3. A nickel layer 5 is provided at the thickness of 0.5-10mum by the spattering method or the like on the back face of the emitter section 1 in contact with the filler material 4. The reduction of the heat transfer quantity from the heater 3 caused when the filler material 4 is sintered during the cathode action and the apparent volume is decreased is suppressed, the production dispersion of products is reduced.</p> |
