PSI - Issue 42

8

P. Ferro et al. / Structural Integrity Procedia 00 (2022) 000 – 000

P. Ferro et al. / Procedia Structural Integrity 42 (2022) 259–269

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Fig. 5. Temperature map (°C) showing the calibrated FZ shape and dimension (red colored) (a) and 3D shape of FZ as a function of welding pass (b)

Fig. 6 shows the variation of  xx stress component after each welding pass as well as the 3D residual stress (RS) distribution after welding. It is observed an increment of  xx stress from the first pass to the last pass. Moreover, the highest values tend to concentrate, after the third pass, closed to the weld toe, where a fatigue crack is commonly observed to nucleate. As expected, the highest RS values are in the longitudinal direction (  zz ) although relevant residual stresses are also in transversal (xx) direction. Due to the low thickness, out-of-plane residual stresses (  yy ) resulted of reduced entity. Boundary effects on RS distribution are also clearly visible in Fig. 6. Due to the insufficient plate width, a stationary RS distribution along the weld line was not reached (Ferro, 2021). Finally, to validate the model, numerical and measured RS were compared in Fig. 7. That picture shows the RS distribution (  xx component only) in the perpendicular direction, over the middle cross section of the welded joint. A reasonable agreement is observed between predicted and measured values that allows considering the model sufficiently reliable and useful for further future investigations about welding of IN625.