Oxide cathode

Abstract

The invention provides an oxide cathode, which particularly comprises the following steps: preparing a cathode-based metal, and reserving a geometric margin on the peripheral surface of an emission layer; pouring nickel powder onto the cathode-based metal by a molding method and putting the entire cathode-based metal together with a mold into a hydrogen furnace for sintering into a nickel sponge layer, reserving a certain geometric margin on the prepared nickel sponge layer, filling the nickel sponge layer with alkali earth metal carbonate, mechanically compacting an emission surface of a cathode emission layer, and removing the residual geometric margin; carrying out pre-decomposition on the oxide cathode before pipe filling; and clamping the oxide cathode on a chuck of a lathe, turning the emission layer and the peripheral surface, removing the residual geometric margin, and then wiping away all particles attached to the cathode surface. The cathode surface provided by the invention becomes smooth, regular, bright and clean; a hot particle emission angle is reduced; deformation of emission electron density distribution is limited; the particle bombardment resistance of the cathode is improved; the sparking probability of the cathode emission surface is reduced; the work stability of the cathode is improved; and the lifetime of the cathode is prolonged.

Description

technical field [0001] The invention relates to electrical components, in particular to an oxide cathode. Background technique [0002] The widespread practice of oxide cathode manufacturing is to prepare a metal sponge layer on the base metal (nickel or tungsten) by molding, and then fill the sponge layer with alkaline earth metal carbonates (binary salt barium carbonate, strontium carbonate; ternary salt Barium carbonate, strontium carbonate, calcium carbonate; quaternary salt barium carbonate, strontium carbonate, calcium carbonate, scandium oxide) to make the emission layer, pre-decompose before use. The flatness, roughness, and cleanliness of the surface of the oxide cathode emission layer directly affect the current size, stability, density distribution and cathode life of the emitted electrons. In order to improve the physical state of the surface of the emission layer, there are two methods disclosed: one method is to divide the emission layer into a top layer a...

AI Technical Summary

Problems solved by technology

Although these methods have improved the roughness and flatness of the surface of the cathode emission layer, the surface of the emission layer is still not smooth, there are certain geometric defects, and there are emitter residues on the surface of the non-emission layer.

The cathode has poor anti-particle bombardment performance, it is easy to spark during work, and there is stray current, which affects the stability and life of the cathode.

Images