Influence of Nonhomogeneous Microstructure of Multi-Pass Weld Metal on Creep Behavior of Cross-Weld Specimen Based on Finite Element Method Available to Purchase

Creep analysis of cross-weld specimen was conducted by numerical method, with the influence of nonhomogeneous microstructure of multi-pass weld metal included. Finite element models were established: one is a 3D simplified model with weld metal considered as homogeneous material, and the other two are 2D and 3D multi-pass models, in which weld metal is composed of columnar grain zone, equiaxed grain zone and recrystallized grain zone. The creep life and maximum damage location predicted by the above models were compared with each other and the effects of the configuration of welding passes, energy input and welding speed were also mentioned. Results indicated that the influence of the nonhomogeneous microstructure of multi-pass weld metal is not obvious at high stress level, while it becomes more remarkable with the decrease of the stress. The creep life of weldment can be extended with intervened arrangement of welding passes. Lower welding speed and energy input may be a candidate option to improve creep properties of weldment.