Verfahren und Vorrichtung zum Elektronenstrahlschweißen

摘要

A method of electron-beam welding with in-process heat treatment comprises the steps of, pre-heating a region of the workpiece 20 to be welded by means of a rastered defocused electron beam, welding said region of the workpiece by focusing the electron beam 22 on the workpiece, simultaneously and subsequently controlling the temperature of regions around the welded region by rastering a defocus electron beam 24, 25. The rastering is in a variable pattern and may be at different beam currents as necessary. The invention also includes a computer controlled electron beam welding apparatus adapted to move the beam in both focused and defocused formats over the workpiece, and to alter the beam current in the defocused mode to achieve a necessary heat input for temperature control. <IMAGE>