Thermal-mechano-metallurgical coupled analysis of welding residual stress

By including the increment of transformation strain into the additive decomposition of the increment of total strain, the constitutive model for thermo-mechano-metallurgical analysis was founded.In this model, the behavior of inhomogeneous multiphase mixture was described by using a homogenizing method.On the basis of the model, the welding residual stress in tubular joint of 9Cr1Mo steel was analyzed by using finite element method.In the numerical simulation, a three-dimensional finite element model is used.The calculated results show that the martensitic transition in tubular joint gradually occurs with the movement of welding heating source.As far as the welding residual stress from the three-dimensional analysis is concerned, both the distribution of it in the axial direction of pipeline and the detailed value of it have a good agreement with the experimental results.