Thermal analysis of heating structure for thermionic cathode electron gun

Some thermal analysis results of several heating structures for thermionic cathode electron gun by using ANSYS code and COMSOL code were presented in this paper, and some instructions for heating structure design were obtained. A series of heating structures of thermionic cathode were tested in experiments, verifying the results of the thermal analysis, and so an efficiency heating structure was attained. In this structure, at a heating power about 100 W, the temperature of cathode was more than 1 900 K which meets at the working temperature required by Ir-Ce cathode. Under a temperature of 1 800 K and the electric field on the cathode surface of 3.6×106 V/m, the Ir-Ce cathode gives a maximum emission current of 1.04 A and the emission current density of 13 A/cm2.