Print Email Facebook Twitter Mechanical performance of auxetic meta-biomaterials Title Mechanical performance of auxetic meta-biomaterials Author Kolken, H.M.A. (TU Delft Biomaterials & Tissue Biomechanics) Lietaert, K. (3D Systems – LayerWise NV) van der Sloten, T. (3D Systems – LayerWise NV) Pouran, B. (University Medical Center Utrecht) Meynen, A. (Katholieke Universiteit Leuven) Van Loock, G. (Katholieke Universiteit Leuven) Weinans, Harrie (TU Delft Biomaterials & Tissue Biomechanics; University Medical Center Utrecht) Scheys, L. (Katholieke Universiteit Leuven; University Hospital Leuven) Zadpoor, A.A. (TU Delft Biomaterials & Tissue Biomechanics) Date 2020 Abstract The innovative design of orthopedic implants could play an important role in the development of life-lasting implants, by improving both primary and secondary implant fixations. The concept of meta-biomaterials aims to achieve a unique combination of mechanical, mass transport, and biological properties through optimized topological design of additively manufactured (AM) porous biomaterials. In this study, we primarily focused on a specific class of meta-biomaterials, namely auxetic meta-biomaterials. Their extraordinary behavior of lateral expansion in response to axial tension could potentially improve implant-bone contact in certain orthopedic applications. In this work, a multitude of auxetic meta-biomaterials were rationally designed and printed from Ti–6Al–4V using a commercially available laser powder bed fusion process called selective laser melting. The re-entrant hexagonal honeycomb unit cell was used as a starting point, which was then parametrically tuned to obtain a variety of mechanical and morphological properties. In this two-step study, the morphology and quasi-static properties of the developed meta-biomaterials were assessed using mechanical experiments accompanied with full-field strain measurements using digital image correlation. In addition, all our designs were computationally modelled using the finite element method. Our results showed the limits of the AM processes for the production of auxetic meta-biomaterials in terms of which values of the design parameters (e.g., re-entrant angle, relative density, and aspect ratio) could be successfully manufactured. We also found that the AM process itself imparts significant influence on the morphological and mechanical properties of the resulting auxetic meta-biomaterials. This further highlights the importance of experimental studies to determine the actual mechanical properties of such metamaterials. The elastic modulus and strength of many of our designs fell within the range of those reported for both trabecular and cortical bone. Unprecedented properties like these could be used to simultaneously address the different challenges faced in the mechanical design of orthopedic implants. Subject Additive manufacturingAuxeticsMeta-biomaterialsMeta-implantsPoisson's ratio To reference this document use: http://resolver.tudelft.nl/uuid:78f68b61-9516-4921-ada7-3ac90b34adab DOI https://doi.org/10.1016/j.jmbbm.2020.103658 ISSN 1751-6161 Source Journal of the Mechanical Behavior of Biomedical Materials, 104 Part of collection Institutional Repository Document type journal article Rights © 2020 H.M.A. Kolken, K. Lietaert, T. van der Sloten, B. Pouran, A. Meynen, G. Van Loock, Harrie Weinans, L. Scheys, A.A. Zadpoor Files PDF 1_s2.0_S1751616119317400_main.pdf 3.55 MB Close viewer /islandora/object/uuid:78f68b61-9516-4921-ada7-3ac90b34adab/datastream/OBJ/view