PSI - Issue 39

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2021) 000–000 il l li t . i i t. tr t r l I t rit r i ( )

www.elsevier.com/locate/procedia . l i r. /l t / r i

ScienceDirect

Procedia Structural Integrity 39 (2022) 120–127

7th International Conference on Crack Paths Residual Notch Stress Intensity Factor assessment via 3D welding numerical simulation: influence of power input Paolo Ferro a *, Keke Tang b , Filippo Berto c numerical simulation: influence of power input a a b c

a University of Padova, Department of Engineering and Management, Stradella S. Nicola, Vicenza, Italy b School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092, China c NTNU, Department of Engineering Design and Materials, Trondheim, Norway ll . i l , i , It l b l f i i li i , ji i it , i , i c , t t f i i i t i l , i , a i it f , t t f i i t, t

Abstract

© 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2021 – Guest Editors Abstract In fusion welded joints fatigue crack originates from the weld toe or weld route due to geometrical discontinuities inducing high stress concentration. This holds true even in presence of residual stress which was found to follow the same asymptotic distribution theorized first by Williams and then, in the elastic-plastic filed, by Hutchinson, Rice and Rosengren. Solid state phase transformations play a fundamental rule in determining the sign of the singular residual stress field. This obviously will influence the crack initiation life in the high cycle fatigue regime where plastic effects at the weld toe can be neglected. In this scenario, the influence of process parameters on the residual asymptotic stress distribution is not yet investigated using a 3D numerical modeling of the welding process. This work is aimed at filling this gap. Computational welding mechanics and the peak stress method are combined to calculate the residual Notch Stress Intensity Factors (R-NSIF) as a function of power input. Results are summarized in terms of heat input and discussed in view of a future guidelines proposal addressed to designers who are going to face a welding process optimization for fatigue life improvement. © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2021 – Guest Editors Keywords: Residual Stress, Peack Stress, Notch Stress Intensity Factor, Welding, Alluminum Alloys i l j i t ti i i t t l t l t t t i l i ti iti i i i t t ti . i l t i i l t i t ll t t ti i t i ti t i i t illi t , i t l ti l ti il , t i , i . li t t t ti l t l l i t i i t i t i l i l t i l . i i l ill i l t i iti ti li i t i l ti i l ti t t t l t l t . t i i , t i l t t i l t ti t i t i ti i t t i ti t i i l li t l i . i i i t illi t i . t ti l l i i t t t i t l l t t i l t t t it t ti i t. lt i i t t i t i i i t i li l t i i t l i ti i ti ti li i t. 021 The Authors. Published by ELSEVIER B.V. i i ti l t li tt :// ti . /li / / . Peer- i i ilit t it : i l tr , tr , t tr I t it t r, l i , ll i ll

* Corresponding author. E-mail address: paolo.ferro@unipd.it rr i t r. - il : l .f rr i .it

2452-3216 © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2021 – Guest Editors I . . This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) r-r i r r i ilit f t it r - t r . li

2452-3216 © 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2021 – Guest Editors 10.1016/j.prostr.2022.03.080