Experimental and computational analysis of residual buckling distortion of bead-on-plate welded joint

A test specimen with a thickness of 2.28 mm was selected as the examined object, to investigate welding induced buckling. Bead-on-plate welding was conducted on the test specimen and residual buckling distortion was observed. A thermal-elastic-plastic (TEP) FE analysis using solid elements model was carried out to predict welding induced buckling after cooling. The inherent deformation of the examined welded joint was also evaluated from the computed results of TEP FE analysis. A shell elements model of the test specimen was used for eigenvalue and elastic FE analyses based on the inherent deformation theory. Eigenvalue analysis predicted the buckling mode and corresponding tendon force in the examined welded joint. Considering large deformation and initial deflection, an elastic FE analysis was carried out to predict the out-of-plane welding distortion, which showed a good agreement with measured distortion. The generation mechanism of buckling in bead-on-plate welded joint was clarified employing the inherent deformation theory. The tendon force (longitudinal inherent shrinkage) is the dominant reason to produce buckling and the disturbance (initial deflection or inherent bending) triggers buckling but does not influence the buckling mode.