Residual stresses in laser-arc hybrid welded butt-joint with different energy ratios

For the laser-arc hybrid welded butt-joint, the width ratio RW was defined to describe the geometrical characteristics of the “wine-glass” weld profile. The energy ratio between arc and laser RQAL (RQAL = Qarc/Qlaser) was introduced as a very important parameter for the formation of the weld profile, the generation of welding deformation and residual stress. The correlation between the energy ratio RQAL and width ratio RW of weld profile was investigated by experimental measurement. The welding deformation and residual stress in laser-arc hybrid welded butt-joints with different energy ratio RQAL were simulated using a 3D thermal elastic–plastic FEM program developed by authors and verified by experimental results. The influence of energy ratio RQAL on the welding deformation and residual stress were discussed in details. Furthermore, the deformation characteristics were well explained by inherent deformation theory.