Investigation and testing of low-temperature emission material for the cathode of a stationary plasma thruster

In this work, a low-temperature emitter was obtained and tested to reduce the power spent on the operation of the cathode-compensator of a stationary plasma engine. The article describes the motivated choice of material, the operating principle of oxide cathode materials, presents the technology for obtaining emitter samples, and describes in detail the developed technological equipment for conducting tests. The research of the samples by X-ray spectral methods showed the uniform distribution of emission-active components. During the tests, the functional dependence of the emitter temperature on the heating power was determined, the values of the thermionic current were measured at fixed values of the heater power, and then the dependences of the emission current on temperature were obtained. At temperatures from 1000 to 1170 °C, the values of the specific electron emission current ranged from 0.25 to 0.70 A. It is expected that when manufacturing a hollow emitter and using it in the design of the cathode unit, that is, under conditions close to natural ones, the current values will be higher with lower energy consumption. In future work, it is planned to manufacture a new batch of low-temperature emitter samples, conduct measurements in a specially designed disassemblable cathode, and achieve a discharge current of up to 0.8 A with a power consumption of less than 50 W.