A new method of experimental investigation of high-power electron beam

Abstract

An equipment for measuring radial current distribution in electron beam produced by technology electron optical system with power up to 10 kW is described. The principle of operation of apparatus and examples of beam characteristics are presented. Two movable plates: one water-cooled protection plate and other- analysing plate behind it are used. Every plate is moving in the direction of one of two perpendicular axis in planes parallel to the focal beam plane. A slit in every plate, which is perpendicular to the axis of its movement, determines the point of beam current density measurement. The electron beam is analysed in the plane where its cross-section is big enough (3–5 mm) relative to a very narrow slit (0.05 mm). The beam changes focus and deflects regularly to avoid melting or damaging of the protection plate. During the measurements of the electron beam current density in any point of beam spot, the electron beam is in a static position and the beam position respectively, measuring the current passing through two slits is one and the same. As a result, high resolution and many details of the current distribution in the beam focus spot can be obtained. This gives a possibility to adjust the electron gun equally in different runs and to obtain the same welding results at other equal technology conditions. A comparison between electron beams of the different electron guns is possible.