Multivariate parametric study on laser beam welding of copper lap joints using adjustable intensity profiles

Abstract

With increasing demand for pure copper welds in the production of electronic connections, various approaches were pursued to reduce the challenging spatter and melt ejection susceptibility of laser beam welding processes in copper materials. One is the use of adjustable intensity profiles of infrared laser beam sources with a combination of a core and ring beam, which enables a wider and more stable keyhole in deep penetration welding and makes a reduction of spattering and melt ejections possible. In order to research the influence of different power distributions with ring powers up to 4000 W and core powers up to 2000 W on the process spattering, welding experiments were evaluated with a stereo camera system for spatter detection using Cu-OF. In addition, the effects of different power distributions, focal positions and welding speeds on the weld metal dimensions and connection widths as well as the corresponding variance were investigated with a multivariate design of experiments based approach.