Quality characteristics and analysis of input parameters on laser beam welding of hairpin windings in electric drives

Abstract The relevance of electric drives in individual mobility is continuously increasing. This requires the use new manufacturing processes automotive production. In modern stators, so-called hairpin winding used. production process entails rectangular copper conductors (hairpin) to be contacted by laser beam welding. To avoid temperature peaks due resistance heating current-carrying wire, a high cross-sectional area welding seam required. Therefore, pore volume must considered. proven thermographic investigations electrically stressed connections. optimize process, effects previous steps and parameters themselves taken into account. paper analyses systematically impact all translational rotational deviations on corresponding quality. tests are performed using disk laser. A spot with focus diameter 170 μm compared statically shaped beam, capable distributing power core ring beam. As an additional parameter, influence oxygen content wire investigated electrolytic tough pitch (Cu-ETP) oxygen-free (Cu-OF). Furthermore, interaction between cutting step before contacting path X-ray computed tomography (CT) used analyse main finding studies significant gap height offset ends resulting area. addition, low static shaping reduce weld spatters, porosity increase stability. Three geometries perform better bridging cause less spatters.