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The effect of architecture on the mechanical properties of cellular structures based on the IWP minimal surface

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Abstract

Architected materials are materials engineered to utilize their topological aspects to enhance the related physical and mechanical properties. With the witnessed progressive advancements in fabrication techniques, obstacles and challenges experienced in manufacturing geometrically complex architected materials are mitigated. Different strut-based architected lattice structures have been investigated for their topology-property relationship. However, the focus on lattice design has recently shifted toward structures with mathematically defined architectures. In this work, we investigate the architecture-property relationship associated with the possible configurations of employing the mathematically attained Schoen’s I-WP (IWP) minimal surface to create lattice structures. Results of mechanical testing showed that sheet-based IWP lattice structures exhibit a stretching-dominated behavior with the highest structural efficiency as compared to other forms of strut-based and skeletal-based lattice structures. This study presents experimental and computational evidence of the robustness and suitability of sheet-based IWP structures for different engineering applications, where strong and lightweight materials with exceptional energy absorption capabilities are required.

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ACKNOWLEDGMENTS

The first and third authors acknowledge the financial support provided by Masdar Institute. The experimental parts were printed using Core Technology Platform resources at NYU Abu Dhabi. We thank Khulood Alawadi for assistance with 3D printing. The authors would also like to thank Alia Abu Ali for helping in designing the BCC lattice structures and Dr. Kamran Khan from Khalifa University of Science, Technology and Research for helping in testing the samples.

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Authors and Affiliations

  1. Mechanical and Materials Engineering Department, Institute Center for Energy, Masdar Institute of Science and Technology, Abu Dhabi, United Arab Emirates

    Oraib Al-Ketan & Rashid K. Abu Al-Rub

  2. Mechanical Engineering Department, Khalifa University of Science and Technology, P.O. 54224, Abu Dhabi, United Arab Emirates

    Oraib Al-Ketan & Rashid K. Abu Al-Rub

  3. Core Technology Platforms, New York University Abu Dhabi, P.O. 129188, Abu Dhabi, United Arab Emirates

    Reza Rowshan

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  1. Oraib Al-Ketan
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Correspondence to Rashid K. Abu Al-Rub.

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Al-Ketan, O., Abu Al-Rub, R.K. & Rowshan, R. The effect of architecture on the mechanical properties of cellular structures based on the IWP minimal surface. Journal of Materials Research 33, 343–359 (2018). https://doi.org/10.1557/jmr.2018.1

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