Electron beam welding with beam focus controlled responsive to absorbed beam power

摘要

In a process for electron beam welding, the electron beam welding gun is controlled to maintain the power absorbed by the pieces being welded substantially constant. In a preferred embodiment the intensity of the electron beam transmitted by the pieces being welded, which corresponds to the power absorbed, is measured, compared with a preset intensity and the difference used to control the focussing current supplied to the gun to maintain the intensity of the transmitted beam constant.