Effect of groove angle on residual stress and deformation of super duplex stainless steel SAF 2507 and austenitic stainless steel 316L dissimilar plasma arc welding

Abstract

Plasma arc welding of super duplex stainless steel SAF 2507 and austenitic stainless steel 316L was carried out by using V‐grooves with different groove angles. In order to predict the temperature distribution during the welding process, the Simufact Welding finite element software was used to establish an equivalent heat source to simulate the plasma arc welding process. The equivalent heat source consists of Goldak heat source and conical heat source. In mechanical simulation, the elastoplastic behavior with isotropic hardening is realized. The numerical results are in good agreement with the experimental results. The results show that with the increase of groove angle, the equivalent stress, transverse residual stress, longitudinal residual stress and overall deformation of SAF 2507/316L dissimilar steel welded joint decrease gradually, and the overall deformation of the joint increases gradually. The groove angle has little influence on the equivalent stress, transverse residual stress and overall deformation, but has great influence on the longitudinal residual stress and Z‐direction deformation. Comprehensive analysis of the stress and deformation results under four groove angles shows that the groove angle is too large or too small, which has a great influence on the stress and deformation of the weldment. The groove angle of 60° is better for SAF 2507/316L dissimilar steel welding.