Design of electron optical system for electron gun for electron beam welding

The design of electron optical system is the key technique for design of electron gun used in (electron) beam welding.The composition of this system is introduced,the four kinds of main physical factors of the structure of electron beam spot are analyzed.On the basis of the technical requirement of local vacuum electron beam welding as well as according to the parameters given,the convergent half-angle,dimensions of light route,and parameters and structure of magnetic lens are obtained by means of calculation.So designed electron gun has following parameters and feature:1) accelerate voltage is 60 kV,electron beam current is 134 mA,i.e.the power of the electron gun is 8 kW;2) electron beam spot diameter on the work piece is 1.6 mm;3) electron optical system of electron gun meets the requirements of local vacuum electron beam welding;4) electron gun can be used on the local vacuum electron beam welding equipment.