INCREASING THE ENERGY EFFICIENCY OF THERMOCATHODES OPERATION

Abstract

The paper presents the results of experimental research on modifying the active area of cathode surfaces applied in the construction of electronic guns and increasing their operating efciency. The intensity of the thermo-electronic emission current is directly proportional to the area of the active surface of the cathodes used for this purpose. To change the micro-geometry of the metal cathode surface, the method of pulsed electric discharge machining (PEDM) was applied. As a result of the application of the discharge plasma on the surface of the cathodes, Taylor cones with heights ranging from 50 to 100 µm were extracted. The analysis of the obtained current-voltage characteristics allows us to compare the values of the saturation current intensities for unprocessed cathodes and those processed by the proposed technology. The increase of the active area of the cathodes with conical asperities causes the increase of the electronic thermoemission current by 10^4. A comparing to the cathodes whose active surfaces have not been processed by this method.