PSI - Issue 61

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2023) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2023) 000 – 000

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Procedia Structural Integrity 61 (2024) 331–339

© 2024 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 the scientific committee of IWPDF 2023 Chairman Abstract Delamination behavior of elastic surface coatings under the effect of thermal shock loading is examined in this study. The multilayered coating system bonded to a metallic substrate is modelled based on finite element method, and computational results are generated using transient thermomechanical analysis. The coating system is loaded on its top surface either cold or hot transient thermal load. Two different cases are considered, which are crack at the interface between the surface coating and the bond coating and crack at the interface between the bond coating and the substrate. Mixed mode (Mode I and Mode II) stress intensity factors and the energy release rate are calculated based on displacement correlation technique and obtained results are compared with those found in ANSYS software. It is observed that results are in a very good agreement. Then, stress intensity factors, energy release rate and phase angle are computed for various cases such as crack length, cold/hot shock, elastic modulus ratio and crack location. It is observed that crack-tip stress field is shear dominant in cold shock while it tends to be opening mode dominant in hot shock case. Moreover, energy release rate for the substrate-bond coating interface crack is larger than that obtained for the surface coating bond coating interface crack, which implies cracks at this surface may be more critical for unstable propagation and failure. © 2024 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 the scientific committee of IWPDF 2023 Keywords: Elastic coating delamination; Hot shock; Cold shock; Displacement Correlation Technique; Finite Element Method. Abstract Delamination behavior of elastic surface coatings under the effect of thermal shock loading is examined in this study. The multilayered coating system bonded to a metallic substrate is modelled based on finite element method, and computational results are generated using transient thermomechanical analysis. The coating system is loaded on its top surface either cold or hot transient thermal load. Two different cases are considered, which are crack at the interface between the surface coating and the bond coating and crack at the interface between the bond coating and the substrate. Mixed mode (Mode I and Mode II) stress intensity factors and the energy release rate are calculated based on displacement correlation technique and obtained results are compared with those found in ANSYS software. It is observed that results are in a very good agreement. Then, stress intensity factors, energy release rate and phase angle are computed for various cases such as crack length, cold/hot shock, elastic modulus ratio and crack location. It is observed that crack-tip stress field is shear dominant in cold shock while it tends to be opening mode dominant in hot shock case. Moreover, energy release rate for the substrate-bond coating interface crack is larger than that obtained for the surface coating bond coating interface crack, which implies cracks at this surface may be more critical for unstable propagation and failure. © 2024 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 the scientific committee of IWPDF 2023 Keywords: Elastic coating delamination; Hot shock; Cold shock; Displacement Correlation Technique; Finite Element Method. 3rd International Workshop on Plasticity, Damage and Fracture of Engineering Materials (IWPDF 2023) Delamination behavior of elastic surface coatings subjected to thermal shock Mehmet N. Balci 1,a, *, Muhammed Aybars Yalcin 2,a,b 3rd International Workshop on Plasticity, Damage and Fracture of Engineering Materials (IWPDF 2023) Delamination behavior of elastic surface coatings subjected to thermal shock Mehmet N. Balci 1,a, *, Muhammed Aybars Yalcin 2,a,b a Department of Mechanical Engineering, Hacettepe University, Beytepe Campus Ankara 06800, Turkey b Turkish Aerospace Industries, Fethiye Mahallesi Havacilik Bulvari, Kahramankazan 06980 Ankara, Turkey a Department of Mechanical Engineering, Hacettepe University, Beytepe Campus Ankara 06800, Turkey b Turkish Aerospace Industries, Fethiye Mahallesi Havacilik Bulvari, Kahramankazan 06980 Ankara, Turkey

* Corresponding author. Tel.: +90 312 297 6208 /147; fax: +90 312 297 6206. E-mail address: mehmetbalci@hacettepe.edu.tr * Corresponding author. Tel.: +90 312 297 6208 /147; fax: +90 312 297 6206. E-mail address: mehmetbalci@hacettepe.edu.tr

2452-3216 © 2024 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 the scientific committee of IWPDF 2023 2452-3216 © 2024 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 the scientific committee of IWPDF 2023

2452-3216 © 2024 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 the scientific committee of IWPDF 2023 Chairman 10.1016/j.prostr.2024.06.042