Determination of the influence of welding parameters on the efficiency of electron beam welding by measurement of backscattered electrons

• Published in: Vacuum 2019-01, Vol.159, p.182-185
• Main Authors: Reisgen, U., Olschok, S., Krichel, T., Gach, S.
• Format: Article
• Language: English
• Subjects: Backscattered current distribution; Backscattered electrons; Efficiency; Electron beam welding
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2018.10.039

Based on the results of a process simulation, a subsequent structural simulation enables a better understanding of metallurgical effects such as solidification and phase transition. The aim of this work is to establish a relationship between welding parameters, seam geometry, efficiency and intensity distribution of backscattered electrons in order to optimize the simulation. For the exact calculation of the energy conversion inside the workpiece the determination of secondary quantities, which enable a metrological recording of the process efficiency, is indispensable. The voltage generated at the measurement resistor is recorded in a detection unit and provides information on the qualitative differentiation and quantitative detection of backscattered and secondary electrons. The power loss is extrapolated from these data. •The welding capillary acts as an electron trap.•With increasing depth-wide ratio A fewer electrons are emitted from the capillary; the efficiency increases.•With constant beam current, an increase in the welding speed leads to a decrease in efficiency.