Evaluation of narrowed weld pool shapes and their effect on resulting potential defects during deep penetration laser beam welding

This study presents mechanisms of the evolution a narrowed region in weld pool center during deep penetration laser beam welding. In numerous numerical studies presented this study, it was also found that local reduction size can cause detrimental effects on melt flow behavior and resulting properties welds. A particularly large influence effect identified three aspects. First, variation solidification sequence causes an increase hot-cracking susceptibility due to locally delayed solidification. Second, proven change length width is associated with adverse impact potential routes molten material induces stronger variations its Thus, element mixing, e.g., welding filler materials, blocked. leads nonhomogeneous chemical composition final undesired properties. Finally, another observed related reduced ability process pores reach top surface. As type porosity usually produced around keyhole tip, fluid regime above area plays significant role determining path until premature middle captures them. summarizes mainly results were supported by selected experimental validation results.