Barium tungsten cathode is one of the most widely used hot cathodes in electric vacuum devices. The porous tungsten sponge substrate is an important component of the impregnated barium tungsten cathode. Its composition, pore size, and pore uniformity directly determine the emission performance and life of the impregnated barium tungsten cathode. In order to further improve the overall performance of the pure barium tungsten cathode, an appropriate amount of rhenium element can be added to it.
The steps for preparing the tungsten-rhenium-based barium-tungsten cathode are as follows:
(1) Prepare NH4ReO4 (ammonium perrhenate) aqueous solution: dissolve NH4ReO4 crystal powder in deionized water, and heat the solution to above 60°C to completely dissolve the NH4ReO4 crystals;
(2) Immerse the sintered porous tungsten substrate in NH4ReOyK solution to allow the porous tungsten substrate to adsorb the NH4ReO4 solution, and the porosity of the porous W substrate is 18% to 30%;
(3) Bake and sinter the porous tungsten substrate that adsorbs the NH4ReO4 solution to convert it into a W-Re substrate;
(4) Immerse aluminate in the W-Re substrate and coat it to complete the manufacture of the tungsten-rhenium-based barium-tungsten cathode.
This production technology method can improve the doping uniformity of Re in the W-Re substrate, so that the Re in the W substrate can uniformly adsorb oxygen inside and on the surface of the W substrate pores during the cathode operation to free the active substance barium, thereby improving the cathode emission performance and stability reliability and extending the cathode life.
More details of tungsten barium electrode or tungsten barium cathode, please visit website: http://tungsten.com.cn/barium-tungsten-cathode.html
Please contact CHINATUNGSTEN ONLINE for inquiry and order of tungsten needles:
Email: sales@chinatungsten.com
Tel.: +86 592 5129595
