Abstract:
Based on the butt joint of Inconel 625 nickel-based alloy tube, the three-dimensional thermal and mechanical finite element model was established. The ANSYS software was used to simulate the residual stress of the nickel-based alloy tube after girth welded by the symmetry welding method, and the simulated distribution of axial and hoop residual stress on outer surface of the tube were analyzed and verified by experiment. In addition, the effect of the preheating temperatures on the residual stresses was investigated. The results show that the axial and hoop residual stress distribution on outer surface of the tube obtained by simulation coincided well with the experimental results, indicating the accuracy of the simulation model. The axial residual compressive stresses and hoop residual tensile stresses formed on outer surface of the weld and near weld zone. With the increase of the distance from the weld center line, the axial compressive stress gradually turned to tensile stress and hoop tensile stress to compressive stress, and then tended to zero. The axial and hoop residual stresses both decreased with the increase of the preheating temperature.