The influence of node coupling on welding deformation and residual stress of T-joint welding root

Abstract

High accuracy and high efficiency is the key to the application of structural welding simulation. To explore the influence of welding root node coupling on the precision of finite element establishing model, the finite element model of T-joint with coupling and uncoupling of nodes in welding root is established. The welding deformation and residual stress distribution of T joint are obtained, and the test results are verified. The results show that, from the trend, the welding deformation and residual stress results are all consistent with the distribution trend of measured results, which proves the correctness and validity of the finite element model. The maximum error of the node uncoupling calculation results and the experimental results is 5.4%, and the maximum error of the node coupling calculation results is 12.2%. The results of the welding root node uncoupling are more close to the actual measurement results. At the same time, the residual stress gradient near the weld seam and heat affected zone changes greatly, and the coupling of the welding root nodes has little influence on the residual stress distribution, and there are three wave peaks. The two treatments have the same trend of stress distribution curve, and the peak value is similar. The peak value of residual stress of node coupling is 303.9MPa, and the peak value of residual stress of node uncoupling is 304.5MPa. The error between welding root node uncoupling and the test result is 4.9%, and the error of node coupling is 7.7%. Therefore, it is suggested that the welding root of T-joint should be node coupling. The research results have important guiding significance for improving the prediction accuracy of welding simulation.