PSI - Issue 39

ScienceDirect Structural Integrity Procedia 00 (2019) 000–000 Structural Integrity Procedia 00 (2019) 000–000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceD rect Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 39 (2022) 364–378

© 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 this study fatigue crack growth tests were carried out on hollow cylindrical specimens, made of D16T and B95AT aluminum alloys (analogue of 2024 and 7075 aluminum), with initial external semi-elliptical surface cracks and undergoing complex stress state. The crack growth behavior of aforementioned materials was studied under cyclic axial tension, pure torsion and combined tension+torsion fatigue loading. Optical microscope measurements and the crack mouth opening displacement (CMOD) method were respectively used to monitor crack length and calculate crack depth. The experimental crack front positions were highlighted by using a beach mark procedure during the tests. The stress strain field along the crack front of semi-elliptical cracks in the cylindrical hollow specimens was assessed by Finite Element Method (FEM) analysis. The stress intensity factors (SIFs) were calculated by the 3D M -integral approach and the distributions of equivalent elastic SIFs along the crack front were used for crack growth rate assessment under mixed mode conditions. As a result, the fracture resistance parameters of aluminum alloys under complex stress state were presented. The simulation of cracks propagation turned out to be consistent with experimental results. © 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: s urface cracks; aluminum alloys; complex stress state; numerical simulation; FEM; mixed mode fracture 1. Introduction The design process of cylindrical components of aircraft structures, pressure vessels and piping is typically very demanding when these structural elements undergo multiaxial loading conditions, including cyclic 7th International Conference on Crack Paths Mixed mode surface crack growth in aluminium alloys under complex stress state R. Yarullin a * , V. Shlyannikov a , D. Amato b , R. Citarella b a Institute of Power Engineering and Advanced Technologies, FRC Kazan Scientific Center of RAS, Russia b Department of Industrial Engineering, University of Salerno, Italy Abstract In this study fatigue crack growth tests were carried out on hollow cylindrical specimens, made of D16T and B95AT aluminum alloys (analogue of 2024 and 7075 aluminum), with initial external semi-elliptical surface cr cks and undergoing complex stress state. The crack growth behavior of aforementioned materials was studied under cyclic axial tension, pure torsion and combined tension+torsion fatigue loading. Optical microscope easurements an the crack mouth opening displacement (CMOD) etho were respectively used to mo itor cra k length and calculate crack depth. The experimental crack front positions were highlighte by using a beach mark procedure during the tests. The stress strain field along the crack front of semi-elliptical cracks in the c lindrical hollow specimens was assessed by Finite Elem nt Method (FEM) analysis. The stress intensity factors (SIFs) wer alculated by the 3D M -integral pproach and the distributions of equivalent elastic SIFs along th crack front were used for crack growth rate assessment under mixed mode conditions. As a result, the fracture resistance parameters of aluminum alloys under complex stress state were presented. The simulation of cracks propagation turned out to be consistent with experimental results. © 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: s urface cracks; aluminum alloys; complex stress state; numerical simulation; FEM; mixed mode fracture 1. Introduction The design process of cylindrical components of aircraft structures, pressure vessels and piping is typically very demanding when these structural elem t undergo multiaxial loading conditions, including cyclic 7th International Conference on Crack Paths Mixed mode surface crack growth in aluminium alloys under complex stress state R. Yarullin a * , V. Shlyannikov a , D. Amato b , R. Citarella b a Institute of Power Engineering and Advanced Technologies, FRC Kazan Scientific Center of RAS, Russia b Department of Industrial Engineering, University of Salerno, Italy

* Corresponding author. Tel.: +7-843-236-31-02; fax: +7-843-236-31-02. E-mail address: yarullin_r@mail.ru * Corresponding author. Tel.: +7-843-236-31-02; fax: +7-843-236-31-02. E-mail address: yarullin_r@mail.ru

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 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

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.2022.03.105