Research of electron beam generator in precision welding by laser heating cathode

At present, many industrial fields of electron beam (EB) welding need high accurate welding technology that is up to the quality of electron beam. Exploratory research in which the field of EB gun is based on laser heating cathode avoids the effect of filament current magnetic field to electron beam. The energy density of EB is more concentrated, and the energy distribution is a kind of perfect gauss distribution. At the same time, the spot size of electron beam is smaller than traditional electron beam gun. Because the way of laser heating cathode, a new technique, is adopted, the lifetime of cathode is increased to 200 h. Because of all advantages of the technique, the heat input of workpiece is decreased during welding process that leads deformation of workpiece to be diminished. So this technique is specially fit to apply these field of high accurate welding field, micro-nano manufacturing process, drilling hole and high accurate 3D rapid prototyping manufacture. © 2014 Journal of Mechanical Engineering.