ELECTRON BEAM WELDING METHOD Russian patent published in 2002 - IPC

FIELD: electron beam welding, possibly of construction materials with control of specific power of electron beam directly at welding process. SUBSTANCE: method comprises steps of modulating specific power of electron beam due to applying alternating components on electric current of electron beam and electric current of focusing lens of electron gun; realizing modulation of electron beam by frequency significantly exceeding modulation frequency of electric current of focusing lens; separating alternating component of secondary electric current with frequency equal to modulation frequency of electric current of electron beam; detecting amplitude of said component; then synchronously detecting received signal at frequency equal to modulation frequency of electric current of focusing lens; setting focusing of beam according to value and sign of voltage received after synchronous detection of signal. Method allows to achieve enhanced accuracy of controlling electron beam focusing and it provides enlarged manufacturing possibilities as after processing secondary electric current with use of amplitude and synchronous detection, signal is generated whose value and sign allow to set mode of electron beam focusing. Said signal allows to evaluate fluctuation of focusing electric current from value corresponding to fine focusing of electron beam providing maximum fusion depth at predetermined values of accelerating voltage and electric current of electron beam. EFFECT: enhanced accuracy of control of electron beam focusing, possibility for realizing electron beam welding at different modes of beam focusing, namely, with use of underfocused and overfocused beams. 1 dwg