Abstract: An electron-beam apparatus for thermal treatment by electron bombardment, comprising a power supply, a vacuum chamber accomodating an object being treated, an electron gun including a cathode which is the source of an electron flow and an accelerating electrode which, together with the cathode, forms the electron flow into an electron beam directed to the object being treated, and a supplementary source of accelerating voltage, one leadout which is connected to the cathode and the other leadout is coupled to the accelerating electrode, the cathode and the accelerating electrode being electrically insulated from each other and from the object being treated, and the power supply has one of its leadouts connected to the cathode and the other leadout connected to the object being treated.

Abstract: An electron beam unit for heat treatment by the electron bombardment technique wherein the resistor for limiting the discharge current arising in the vacuum chamber between the cathode and the accelerating electrode of the electron beam gun is connected between the positive pole of the power supply and the accelerating electrode, the accelerating electrode being insulated from the material being processed by means of an insulator.