Title
Additively manufactured metallic porous biomaterials based on minimal surfaces: A unique combination of topological, mechanical, and mass transport properties
Author
Bobbert, F.S.L. (TU Delft Biomaterials & Tissue Biomechanics) 
Lietaert, K. (Katholieke Universiteit Leuven; 3D Systems)
Eftekhari, A.A. (Technical University of Denmark)
Pouran, B. (TU Delft Biomaterials & Tissue Biomechanics; University Medical Center Utrecht)
Ahmadi, S.M. (TU Delft Biomaterials & Tissue Biomechanics)
Weinans, Harrie (TU Delft Biomaterials & Tissue Biomechanics; University Medical Center Utrecht)
Zadpoor, A.A. (TU Delft Biomaterials & Tissue Biomechanics)
Date
2017
Abstract
Porous biomaterials that simultaneously mimic the topological, mechanical, and mass transport properties of bone are in great demand but are rarely found in the literature. In this study, we rationally designed and additively manufactured (AM) porous metallic biomaterials based on four different types of triply periodic minimal surfaces (TPMS) that mimic the properties of bone to an unprecedented level of multi-physics detail. Sixteen different types of porous biomaterials were rationally designed and fabricated using selective laser melting (SLM) from a titanium alloy (Ti-6Al-4V). The topology, quasi-static mechanical properties, fatigue resistance, and permeability of the developed biomaterials were then characterized. In terms of topology, the biomaterials resembled the morphological properties of trabecular bone including mean surface curvatures close to zero. The biomaterials showed a favorable but rare combination of relatively low elastic properties in the range of those observed for trabecular bone and high yield strengths exceeding those reported for cortical bone. This combination allows for simultaneously avoiding stress shielding, while providing ample mechanical support for bone tissue regeneration and osseointegration. Furthermore, as opposed to other AM porous biomaterials developed to date for which the fatigue endurance limit has been found to be ≈20% of their yield (or plateau) stress, some of the biomaterials developed in the current study show extremely high fatigue resistance with endurance limits up to 60% of their yield stress. It was also found that the permeability values measured for the developed biomaterials were in the range of values reported for trabecular bone. In summary, the developed porous metallic biomaterials based on TPMS mimic the topological, mechanical, and physical properties of trabecular bone to a great degree. These properties make them potential candidates to be applied as parts of orthopedic implants and/or as bone-substituting biomaterials.
Subject
Porous biomaterials
Selective laser melting
Ti-6Al-4V
Bone regeneration
Implant fixation
To reference this document use:
http://resolver.tudelft.nl/uuid:e530c7cc-5297-472d-b09c-0bc4dc903713
DOI
https://doi.org/10.1016/j.actbio.2017.02.024
Embargo date
2017-08-16
ISSN
1359-6454
Source
Acta Materialia, 53, 572-584
Bibliographical note
Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
Part of collection
Institutional Repository
Document type
journal article
Rights
© 2017 F.S.L. Bobbert, K. Lietaert, A.A. Eftekhari, B. Pouran, S.M. Ahmadi, Harrie Weinans, A.A. Zadpoor