Investigation of the possibility of using a deflecting system for magnetic fields impact compensation during electron-beam welding

The impact of magnetic fields caused by thermoelectric currents and residual magnetization of the welded parts on the accuracy of an electron beam positioning along the welded joints is a complicated scientific and technical problem to achieve high quality of welds in the aerospace industry, shipbuilding and power engineering. Presented in the article mathematical models of distribution of magnetic fields of interference in the space between the electron beam gun and the surface of a welding workpiece and also inside a workpiece allow to culculate the quantitative characteristics of the electron beam deflection from welded joints. The authors propose to use a deflection system for compensation of mag- netic interference impact. The deflection system must be set to a certain height above the workpiece to be welded. The authors obtained a mathematical model of the magnetic field induction of the deflecting system distribution along its axis which coincides with the optical axis of the electron beam gun. The coordinates of installation of the deflection system concerning the surface of the parts to be welded are determined using the presented mathematical models. Cal- culations showed that the height of installation of deflection system depends on the thickness of the welded components. Using the deflection system installed at a certain height above the workpiece to be welded allows to eliminate the impact of magnetic fields caused by thermoelectric currents and residual magnetization of the welded parts on the quality of welded joints.