The hot cracking susceptibility subjected the laser beam oscillation welding on 6XXX aluminum alloy with a partial penetration joint

A laser beam oscillation method using Galvano mirrors, which allows wide weld beads and controls thermal stress distribution, was suggested to suppress the formation of solidification cracks in laser welds. In order to understand the solidification cracking behavior in relation to the bead shape, laser beam oscillation welding was performed under various oscillation widths and frequency conditions. To evaluate the effect of the oscillation parameter on solidification cracking susceptibility, a regression analysis based on the shape of the bead was performed. Stress distribution generated during the laser beam oscillation welding process was also analyzed using finite element modeling simulation. From the results, it was demonstrated that a high shrinkage stress field at the bottom of the partial penetrated bead suppresses the solidification cracking.