PSI - Issue 83

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ScienceDirect

Procedia Structural Integrity 83 (2026) 218–228

The fourth European Conference on the Structural Integrity of Additively Manufactured Materials (ESIAM26) Axial crushing behavior of additively manufactured aluminum alloy Menger fractal structures: Finite element simulations Kemal Arslan a,b, *

a Department of Aeronautical Engineering, Erciyes University, Kayseri 38030, Türkiye b Department of Mechanical Engineering, Politecnico di Milano, Milano 20156, Italy

© 2026 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 the ESIAM26 organizers Abstract Lightweight high-energy-absorbing structures play a critical role in ensuring crashworthiness in transportation, aerospace, and impact protection systems. Conventional thin-walled metallic structures, such as aluminum and steel tubes, have been widely employed as energy absorbers due to their well-understood energy absorption mechanisms under dynamic crushing loads. Advances in additive manufacturing have facilitated the production of complex cellular and architected structures that are not achievable using traditional manufacturing methods. Among these, fractal-based geometries, such as Menger sponge-inspired structures, can offer opportunities to improve energy absorption efficiency through hierarchical porous architectures. This study numerically investigates the dynamic axial crushing response of additively manufactured aluminum alloy Menger fractal tubular structures and compares their energy absorption performance with that of a conventional steel tube using the finite element method. FEM simulations were performed using the explicit finite element code, LS-DYNA. The first- and second-order Menger fractal structures were considered for the analysis, and the original geometric dimensions of the removed cubic elements were modified to obtain approximately the same mass as the steel tube. The numerical results show that the second-order Menger fractal structure exhibits a more stable and controlled axial deformation profile than the first-order fractal structure and the steel tube, while also eliminating the undesirable high initial peak force in crash box designs. These findings indicate that Menger fractal structures with optimized geometric dimensions have promising potential for crashworthiness applications.

* Corresponding author. Tel.: +90-352-207-6666 E-mail address: karslan@erciyes.edu.tr Visiting Researcher at Politecnico di Milano

2452-3216 © 2026 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 the ESIAM26 organizers 10.1016/j.prostr.2026.07.025