Abstract: A method for determining the element concentration in electron beam melting is used for the continous measurement during the melting process especially for melting alloys. According to the invention, the X-radiation generated during melting is utilized by concurrently measuring the intensity of the characteristic radiation of the element to be determined and the intensity of another portion of the X-ray spectrum from the same location of the melt. The quotient of both measurands then is a function of the concentration of the element to be determined.

Abstract: A high beam power electron gun of the axial type, particularly useful in large-scale vacuum metallurgy plants for melting, vaporizing and heat treating. The electron gun is controllable over its entire power range, i.e., from 10% to 100% of its nominal power, while the focal length of its beam guidance lens is maintained unchanged. This lens is downstream of a cathode, a focusing electrode and a movable anode, and is provided on its upstream side with a pole shoe to which the anode is fastened and which, together with the anode, is movable as a single unit in the axial direction for controlling the power.