Simulation of Anode Material Erosion in the Internal Environment of HPM Devices

Abstract

Summary form only given. The internal environment of a high-vacuum HPM source is subjected to intense electron flow impact resulting in possible rapid erosion of the interior material (anode, collector, etc.) leading to limitation of the operational lifetime and even to accidental damage and failure of the whole device during its operation. In relativistic magnetrons, for example, the anode electrode is subjected to electron flow impact with electron kinetic energy of 350-500 kV, pulse duration up to several 100 ns and power density of hundreds MW per sq. cm. A research program was initiated recently at the University of New Mexico to study anode phenomena in high-power magnetrons. In accordance with the research plan a series of computer experiments have been performed aimed at studying the intense high-voltage and high-current electron flow interaction with matter. In the simulations, the high-energy electron flow penetration into matter as a function of angle of incidence, incident electron energy and magnetic field orientation have been simulated using the Monte-Carlo code MONSOL, which was developed to calculate charged particle trajectories in matter. The erosion of material subjected to pulsed high-density, high-voltage electron flow has been simulated as a function of the electron flow parameters (pulse duration, current density, electron kinetic energy) using the elastic-plastic continuum media dynamics code BETAINE developed for studying dynamic characteristics of an irradiated targets (stresses, density, velocity distributions, phase state of substance). Some results of these simulations are presented showing the dependence of the electron-impact erosion phenomena on the operational parameters of relativistic magnetrons