Electron emission phenomenon of cathode evaporator

In order to study the electron emission phenomenon of evaporator of an impregnated cathode, a special device is designed, which includes barium tungsten cathode, tungsten receiver, vacuum system, data acquisition unit, etc. The characteristics of the impregnated cathode are as follows: Φ 8.0 mm x 2.5 mm, 25% porosity of porous tungsten matrix, 6BaO/CaO/2Al₂O₃ impregnant. While the tungsten receiver cathode is a polished polycrystalline tungsten wafer with the size of Φ 3.5 mm x 1.0 mm. The relative distance between the two cathodes is 1.0 mm.