Investigation of welding residual stress distribution in a thick-plate joint with an emphasis on the features near weld end-start

In this study, an advanced computational approach with considering moving heat source, temperature-dependent material properties, strain-hardening and annealing effect was developed to predict welding temperature field, residual stress distribution and deformation in multi-pass welded joints. The welding residual stress distributions in austenitic stainless steel thick-plate multi-pass joints performed by the different deposition patterns and different deposition directions were simulated through using the developed computational procedure. Based on the numerical results, the features of residual stress distribution near the weld end-start location were examined. Meanwhile, experiments were carried out to measure the welding residual stress distributions in two mock-ups. The numerical results are generally in a good agreement with the experimental measurements. Both experiment and numerical model show that the distribution of welding residual stress near the weld end-start location has an apparent discontinuous feature. The research results indicate that deposition pattern has a significant influence on welding residual stress, and it not only can change the distribution shape of residual stress but also can alter the peak value of residual stress. Under the condition of identical deposition pattern, the distribution of welding residual stress seems not sensitive to deposition direction.