The weldability of zinc coated steel sheets is often compromised by weld seam defects caused by rapid zinc vaporisation and burned-off zinc. Owing to this, welded seams usually remain unprotected from corrosion and are accompanied by undesirable porosity. In this paper, the laser droplet generation process and its application to laser droplet welding of zinc coated steel sheets are described. The influences of laser droplet generation and welding process control parameters on the properties of joints of zinc coated steel sheets are presented. Results show that laser droplet welding offers a promising technology for spot and continuous welding of zinc coated steel sheets in different joint configurations with good mechanical properties and corrosion resistance.
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