Advanced electron beam gun design for high integrity processing

Electron beam technology is a unique technology that enables joining dissimilar and otherwise hard to weld metals with very precise and clean welds while minimizing the heating of the material outside the working area. In recent years, the use of this technology in additive manufacturing has become an exciting opportunity as this would reduce the operational cost of the technology and improve its versatility and performance. A shortcoming of the current technology is the slow thermal response and short lifetime of conventional thermionic electron sources, which hinders the exploitation of electron beam technology in additive manufacturing applications.
In this project we will investigate the use of a plasma cathode instead of thermionic emission as a source of electrons to overcome these limitations. The student will be undertaking experimental and computational work to design, fabricate and characterise different plasma cathodes while assessing their feasibility as electron sources for electron guns. Due to the pressure range at which the electron gun must operate at, modelling of the plasma will require the use of a kinetic approach and it is anticipated that a Particle-in-cell Monte Carlo collision model will be used in the study.