Fatigue behavior of SMA490BW welded components considering AHT with traction structural stress

Quantitative characterization on fatigue properties of SMA490BW welded components with annealing heat treatment is very significant for steel structure service. In this work, the relief of residual stress during welding and the subsequent annealing heat treatment process of plate and tube-to-plate components is simulated using the finite element method with the Norton-Bailey creep model. Traction structural stress is used to evaluate the fatigue life of SMA490BW plates and tube-to-plate components under two annealing heat treatment processes by considering residual stress. It is found that the residual stress distribution state of welded components keeps the same tendency by annealing heat treatment, while the peak value of longitudinal and transverse residual stress is decreased significantly due to the increase of equivalent creep strain with the width of the welded plate exceeding 6 times the thickness. The fatigue data for two annealing heat treatment processes and welding of plate and tube-to-plate components are within a 95% confidence interval of the ASME Master S-N curve. The influence of load range on fatigue life is more significant than that of welding residual stress. By quantifying the residual stress in the load ratio correction, the standard deviation of fatigue data for different full-scale components more convergent.