Sintered Tungsten Wire Cathodes

At IVEC 2006, Calabazas Creek Research, Inc. (CCR) reported on a novel technique to fabricate controlled porosity cathodes. In this process, 20 micron diameter tungsten wires are bundled and sintered to create a porous structure where the pores penetrate through the length of the material. With control of the packing, wire size, and length, the material should be ideal for caps on reservoir cathodes. The parameters could be selected to provide the desired barium diffusion, depending on the required life time and current emission density. This article shows a cross section of sintered tungsten wires. CCR is fabricating a test cathode from this material. Assembly is almost complete and testing is scheduled for February 2007. The latest test results will be presented.