Simulation of keyhole laser welding of stainless steel plates with a gap

Abstract The presence of a gap (from tens to hundreds of microns) between two components may cause defects during laser-welding processes. Within this paper the process is investigated for two stainless steel plates in overlap configuration by means of multiphysyical CFD modeling. As a first step modeling results are compared with experimental data. Then the gap influence on the fluid dynamics and on the appearance of welding defects are analyzed. Based on the results adapted beam shapes are proposed that allow for an optimized energy distribution and thus an improved weld quality.