PSI - Issue 68

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ScienceDirect

Procedia Structural Integrity 68 (2025) 573–580 Procedia Structural Integrity 00 (2024) 000–000 Procedia Structural Integrity 00 (2024) 000–000

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European Conference on Fracture 2024 A numerical study of the ballistic performance of multi-layered European Conference on Fracture 2024 A numerical study of the ballistic performance of multi-layered

targets through uncoupled damage models Hande Vural, Su¨meyye Tekbas¸, Nazlıcan Go¨kdemir, Tuncay Yalc¸inkaya ∗ Department of Aerospace Engineering, Middle East Technical University, 06800 Ankara , Tu¨rkiye targets through uncoupled damage models Hande Vural, Su¨meyye Tekbas¸, Nazlıcan Go¨kdemir, Tuncay Yalc¸inkaya ∗ Department of Aerospace Engineering, Middle East Technical University, 06800 Ankara , Tu¨rkiye

Abstract Ballistic-resistant structures are vital in the defense and aerospace industries, designed to provide e ff ective protection by balancing material thickness and weight. Multi-layered configurations that combine the strengths of di ff erent materials o ff er improved ballistic resistance and provide ease of maintenance. The performance of such structures is a ff ected by parameters such as material type, thickness and layer sequence, highlighting the need for further research. In multi-layer ballistic impact studies, damage models such as Johnson-Cook (JC), modified Mohr-Coulomb (MMC) and Cockcroft-Latham (CL) are commonly used to predict the resistance capacity and failure of targets. In the present study, various uncoupled damage models such as Ayada, Ayada-m, Brozzo, KH, Le-Roy (LR), McClintock (MC), Oh (OH), Rice-Tracey (RT), CL, Fredenthal are implemented in Abaqus and applied to assess the ballistic performance of Armox 500T. The ability of the models to predict failure modes and residual velocity according to the impact velocity and bullet nose shape with di ff erent layer combinations is discussed in detail. Abstract Ballistic-resistant structures are vital in the defense and aerospace industries, designed to provide e ff ective protection by balancing material thickness and weight. Multi-layered configurations that combine the strengths of di ff erent materials o ff er improved ballistic resistance and provide ease of maintenance. The performance of such structures is a ff ected by parameters such as material type, thickness and layer sequence, highlighting the need for further research. In multi-layer ballistic impact studies, damage models such as Johnson-Cook (JC), modified Mohr-Coulomb (MMC) and Cockcroft-Latham (CL) are commonly used to predict the resistance capacity and failure of targets. In the present study, various uncoupled damage models such as Ayada, Ayada-m, Brozzo, KH, Le-Roy (LR), McClintock (MC), Oh (OH), Rice-Tracey (RT), CL, Fredenthal are implemented in Abaqus and applied to assess the ballistic performance of Armox 500T. The ability of the models to predict failure modes and residual velocity according to the impact velocity and bullet nose shape with di ff erent layer combinations is discussed in detail. © 2025 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 ECF24 organizers © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Structures such as armored vehicles and shields manufactured in the defense and aviation industries are designed to resist ballistic loads. Analyzing a response of target to impact loads enables the design and production of stronger and more durable structures. High-strength metals such as steel are generally preferred as target materials, and the ballistic performance of these materials depends not only on material properties but also parameters such as the thickness of the target, impact velocity and bullet nose shape. In addition to these parameters, studies have also focused on multilayer structures to enhance ballistic performance, especially for wearable military equipment (Palta et al. (2018)). By optimizing ballistic resistance, these structures enable lighter and more durable designs. Additionally, the ease of replacing damaged plates simplifies repair and maintenance (see, e.g. Teng et al. (2007); Dey et al. (2007)). The fracture behavior of target materials under ballistic impacts can be investigated using the finite element (FE) method and ductile damage models to reduce the high cost of experiments (see e.g. Go¨c¸men et al. (2023)). Uncoupled damage models that include parameters such as plastic deformation, stress triaxiality, deformation rate and tempera- Structures such as armored vehicles and shields manufactured in the defense and aviation industries are designed to resist ballistic loads. Analyzing a response of target to impact loads enables the design and production of stronger and more durable structures. High-strength metals such as steel are generally preferred as target materials, and the ballistic performance of these materials depends not only on material properties but also parameters such as the thickness of the target, impact velocity and bullet nose shape. In addition to these parameters, studies have also focused on multilayer structures to enhance ballistic performance, especially for wearable military equipment (Palta et al. (2018)). By optimizing ballistic resistance, these structures enable lighter and more durable designs. Additionally, the ease of replacing damaged plates simplifies repair and maintenance (see, e.g. Teng et al. (2007); Dey et al. (2007)). The fracture behavior of target materials under ballistic impacts can be investigated using the finite element (FE) method and ductile damage models to reduce the high cost of experiments (see e.g. Go¨c¸men et al. (2023)). Uncoupled damage models that include parameters such as plastic deformation, stress triaxiality, deformation rate and tempera- Peer-review under responsibility of ECF24 organizers. Keywords: ballistic impact; ductile failure; multi-layer Peer-review under responsibility of ECF24 organizers. Keywords: ballistic impact; ductile failure; multi-layer 1. Introduction 1. Introduction

2452-3216 © 2025 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 ECF24 organizers 10.1016/j.prostr.2025.06.099 ∗ Yalc¸inkaya T. Tel.: + 90-312-210-4258 ; fax: + 90-312-210-4250. E-mail address: yalcinka@metu.edu.tr 2210-7843 © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ECF24 organizers. ∗ Yalc¸inkaya T. Tel.: + 90-312-210-4258 ; fax: + 90-312-210-4250. E-mail address: yalcinka@metu.edu.tr 2210-7843 © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ECF24 organizers.