Coupled temperature-displacement analyses were conducted to simulate heat transfer, microstructure evolution and residual stress development in the multi-pass welds of a procedure qualification test for welding nuclear reactor pressure vessels.Commercial FEA package ABAQUS was used as the platform for the analyses in combination of user subroutines developed specifically to model constitutive behaviors of materials in welding processes.Prediction of microstructural evolution was coupled with heat transfer analysis to compute and update microstructural state variables.Effects of phase transformations were considered in the mechanical stress analyses.Predicted distributions of microstructure, mechanical properties and residual stresses from the coupled analyses were compared with the experimentally measured results.