| 摘要 |
<p>The invention relates to a procedure for manufacturing an impregnated cathode for an electron tube and to the impregnated cathode obtained therewith. The method involves mixing (b) a powder (Y) containing the emissive element (generally aluminates of barium and calcium) with the powder (W) of at least one refractory element (generally tungsten, possibly mixed with a platinum ore metal). This is followed by pressing (c) the mixture to form a pellet (1) which is then sintered (d) at a high temperature (about 2000 DEG C) in a hydrogen atmosphere. In the prior art, a powder of at least one refractory metal was pressed and sintered, and then impregnated, machined, cleaned, etc. The method of the invention thus enables many stages in the manufacture of an impregnated cathode to be omitted in comparison with the prior art. <IMAGE></p> |
