Laser beam micro welding with high brilliant fiber lasers

Abstract

Spatial power modulation for laser beam micro welding by superposing an oscillation move-ment to the feed direction is gaining more and more importance, especially for welding of difficult-to-weld materials, e.g. aluminum, copper or zinc-coated steel sheets. Up to now, there are no ade-quate machine techniques available providing oscillation frequencies of more than 5 kHz. Examina-tions about the dynamic behavior of conventional galvanometric scanners with integrated oscillation movement ("wobble function" ) are presented. These systems are commonly used for laser beam mi-cro welding but their dynamic behavior at high oscillation frequencies is not known yet. A focus of the examinations is on alternative scanning systems, presenting their characteristics and their appli-cability for laser beam micro welding. Applications presented are welding experiments for an adapted seam width in bead-on-plate welding.