Numerical and experimental study on prediction of thermal history and residual deformation of double-sided fillet welding

Abstract

Distortions occur in almost every arc welded joint. The nature of the created distortion depends on several parameters including the welding speed, plate thickness, welding current, voltage, and restraints applied to the job. The distortions and thermal history of a joint can be measured experimentally but the measurement procedure may be costly and time-consuming. In the present work a numerical elasto-plastic thermomechanical model has been developed for predicting the thermal history and resulting angular distortions of submerged arc welded double-sided fillet joints. A moving distributed heat source was used in the finite element modelling of the double-sided fillet welding to create a realistic simulation of the process. The effect of filler metal deposition was taken into account by implementing a birth-and-death process for the elements. The transient temperature distributions were predicted using temperature-dependent material properties. The angular distortion profiles were predicted based on the transient temperature distributions of the fillet welds. The model yielded results that match the experimental values (with a variation of 5–10 per cent for the maximum values of the distortions and a variation of 8 per cent for peak temperatures).