Controlled porosity cathodes from sintered tungsten wires

In this paper, we describe a simple technique for controlling the porosity of tungsten cathodes and replacing the barium compound impregnated matrix with a reservoir of barium producing compounds. Consequently, the cathode thus produced yields a uniform work function surface and significantly longer life than porous tungsten cathodes. The process uses existing sintering equipment and readily available, modestly priced materials. It is anticipated that successful development of this process will lead to less expensive, higher quality cathodes.