ved (vacuum electronic device)
V.I. Voronin, G.V. Konushkov, A.A. Lemyakin
The object of the research is the technological process of VED pumping-out with parts’ separation.
The aim of the work is to optimize a technological process which provides the lowest pressure in the VED and helps in reducing negative self-influencing of electrodes at degassing.
For achieving the goal the following theoretical and experimental research has been conducted:
the model of the pumping-out technological process has been developed. It allows taking into consideration parts’ clearance, gas disposal from inter-electrode space and vacuum parameters of the equipment;
the influence of parts’ separation size on the effective pumping-out speed and vacuum conditions of the device degassing has been investigated;
gas flows emitted from electrodes at pumping-out have been searched for finding out optimal conditions of cathode vacuum-thermal treatment.
The theoretical and experimental dependences received allow optimizing VED pumping-out, i.e. maximum eliminate electrodes negative self-influencing.
-VED pumping-out cycle with parts’ separation for 20…25 mm reduces 1,6…1.7 fold in comparison with the VED pumping-out cycle with parts’ separation for 0,5…5,0 mm;
At pumping-out there is an optimal parts’ separation, providing the lowest gas pressure in the device. At the following parts’ separation vacuum and electrical parameters of the device do not change;
At pumping-out electrodes separation in an optimal distance provides improving vacuum-thermal conditions of the cathode treatment at the expense of reducing pressure in the inter-electrode space 1…1,5 fold. Devices working at current density up to 0,25 A/cm2 may be treated in the inter-electrode distance 5…10 mm, and at the current densities up to 1 A/cm2 a cathode and anode should be separated for 15…20 mm. The following electrodes separation does not improve the device parameters.