Proceedings of International Conference on Applied Innovation in IT
2013/03/25, Volume 1, Issue 1, pp.1-6
Electron Beam Welding In-Process Control and Monitoring
Abstract: This work presents the results of an investigation of processes in the melting zone during Electron Beam Welding (EBW) through analysis of the secondary current in the plasma.The studies show that the spectrum of the secondary emission signal during steel welding has a pronounced periodic component at a frequency of around 1525 kHz. The signal contains quasi-periodic sharp peaks (impulses). These impulses have stochastically varying amplitude and follow each other in series, at random intervals between series. The impulses have a considerable current (up to 0.5 A). It was established that during electron-beam welding with the focal spot scanning these impulses follow each other almost periodically. It was shown that the probability of occurrence of these high-frequency perturbation increases with the concentration of energy in the interaction zone. The paper also presents hypotheses for the mechanism of the formation of the high-frequency oscillations in the secondary current signal in the plasma.
Keywords: automation of welding processes, electron beam welding, focus control, focus spot scanning, weld formation monitoring
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