In this paper, an integrated framework for modeling welding processes is presented within the context of residual stress and distortion predictions. At first, the multi-faceted process physics and mechanics associated with welding are briefly outlined based on a rapidly growing knowledge base resulting from some of the current research efforts. Then, an engineering perspective for today's industrial applications is discussed in terms of both feasibility and practicality of the state of the art modeling techniques in the context of residual stress and distortion predictions. As the centerpiece of the integrated framework, a unified constitutive model for finite element simulation of welding processes is discussed in detail. A novel approach using the shell element model for multipass welds is also presented. Finally, a number of examples are presented to demonstrate the applications of the integrated framework in the following areas:1.Microstructure and property evolution in weld metal and HAZ2.Weld material modeling - internal state-variable based constitutive models3.Transient thermomechanical processes4.Residual stress and distortion predictions5.Fracture mechanics analysis incorporating weld residual stresses.The specific examples include microstructure modeling and residual stress prediction for a clad weld, residual stresses in repair welds, and fracture mechanics analysis of a propagating crack subjected residual stress fields in a girth weld.
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