In Nature, despite the diversity of materials, patterns and structural designs, the majority of biomineralized systems share a common feature: the incorporation of multiple sets of discrete elements across different length scales. This paper is the first to assess whether the design features observed in the hexactinellid sea sponge Euplectella aspergillum can be transferred and implemented for the development of new structurally efficient engineering architectures manufactured by three-dimensional (3D) additive manufacturing (AM). We present an investigation into the design and survival strategies found in the biological system and evaluate their translation into a scaled engineering analogue assessed experimentally and through finite-element (FE) simulations. Discrete sections of the skeletal lattice were evaluated and tested in an in situ compression fixture using micro-computed tomography (μCT). This methodology permitted the characterization of the hierarchical organization of the siliceous skeleton; a multi-layered arrangement with a fusion between struts to improve the local energy-absorbing capabilities. It was observed that the irregular overlapping architecture of spicule–nodal point sub-structure offers unique improvements in the global strength and stiffness of the structure. The 3D data arising from the μCT of the skeleton were used to create accurate FE models and replication through 3D AM. The printed struts in the engineering analogue were homogeneous, comprising bonded ceramic granular particles (10–100 µm) with an outer epoxy infused shell. In these specimens, the compressive response of the sample was expected to be dynamic and catastrophic, but while the specimens showed a similar initiation and propagation failure pattern to E. aspergillum , the macroscopic deformation behaviour was altered from the expected predominantly brittle behaviour to a more damage tolerant quasi-brittle failure mode. In addition, the FE simulation of the printed construct predicted the same global failure response (initiation location and propagation directionality) as observed in E. aspergillum . The ability to mimic directly the complex material construction and design features in E. aspergillum is currently beyond the latest advances in AM. However, while acknowledging the material-dominated limitations, the results presented here highlight the considerable potential of direct mimicry of biomineralized lattice architectures as future light-weight damage tolerant composite structures.

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A critical challenge underpinning the adoption of Additive Manufacture (AM) as a technology is the postprocessing of manufactured components. For Powder Bed Fusion (PBF), this can involve the removal of powder from the interior of the component, often by vibrating the component to fluidise the powder to encourage drainage. In this paper, we develop and validate a computational model of the flow of metal powder suitable for predicting powder removal from such AM components. The model is a continuum Eulerian multiphase model of the powder including models for the granular temperature; the effect of vibration can be included through appropriate wall boundaries for this granular temperature. We validate the individual sub-models appropriate for AM metal powders by comparison with in-house and literature experimental results, and then apply the full model to a more complex geometry typical of an AM Heat Exchanger. The model is shown to provide valuable and accurate results at a fraction of the computational cost of a particle-based model.