Influence of welding sequence on residual stress distribution and deformation in Q345 steel H-section butt-welded joint

Based on Marc. MSC software, this paper developed a thermo-elastic-plastic finite element method (FEM) to simulate the welding residual stresses and deformation in the low alloy high strength steel joints. The welding residual stresses and deformation in the Q345 Steel H-section butt-welded joints were calculated using this method. An H-section butt-welded joint was fabricated and the welding residual stresses were measured. Based on the simulation and experiment, the influence of welding sequence on the residual stress distribution and deformation in the Q345 steel H-section butt-welded joint was investigated. The results indicate that the welding sequence has a relatively small effect on the residual stress distribution in the flanges of the H-section joints, but a significant influence on that in the web. Under three different welding sequences, the welding deformations in the joints were similar. In the view of controlling welding residual stress, welding the web first is recommended in the fabrication of the H-section butt-welded joint.