A SIMPLE-MODEL OF A GLOW-DISCHARGE ELECTRON-BEAM FOR MATERIALS PROCESSING

A simple semiempirical model of the electron beam generated by a pulse d cold cathode electron gun has been developed. The model describes an alytically the observed self-focusing of the discharge and predicts th e dynamical variation of the focal distance, in good agreement with ex periments, This effect plays a major role in the determination of the effective duration of the energy pulse, The model was used to conduct simple calculations of energy thresholds for melting of solid material s, giving helpful insight on ranges of operation of this kind of elect ron gun for its application to material processing, A comparison with available experimental data for Mg70Zn30 samples is given.