Significant developments in the field of additive manufacturing (AM) allowed the fabrication of complex microarchitectured components with varying porosity across different scales. However, due to the high complexity of this process, the final parts can exhibit significant variations in the nominal geometry. Computer tomographic images of 3D printed components provide extensive information about these microstructural variations, such as process-induced porosity, surface roughness, and other undesired morphological discrepancies. Yet, techniques to incorporate these imperfect AM geometries into the numerical material characterization analysis are computationally demanding. In this contribution, an efficient image-to-material-characterization framework using the high-order parallel Finite Cell Method is proposed. In this way, a flexible non-geometry-conforming discretization facilitates mesh generation for very complex microstructures at hand and allows a direct analysis of the images stemming from CT-scans. Numerical examples including a comparison to the experiments illustrate the potential of the proposed framework in the field of additive manufacturing product simulation.

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The field of biomedical design and manufacturing has been rapidly evolving, with implants and grafts featuring complex 3D design constraints and materials distributions. By combining a new coding‐based design and modeling approach with high‐throughput volumetric printing, a new approach is demonstrated to transform the way complex shapes are designed and fabricated for biomedical applications. Here, an algorithmic voxel‐based approach is used that can rapidly generate a large design library of porous structures, auxetic meshes and cylinders, or perfusable constructs. By deploying finite cell modeling within the algorithmic design framework, large arrays of selected auxetic designs can be computationally modeled. Finally, the design schemes are used in conjunction with new approaches for multi‐material volumetric printing based on thiol‐ene photoclick chemistry to rapidly fabricate complex heterogeneous shapes. Collectively, the new design, modeling and fabrication techniques can be used toward a wide spectrum of products such as actuators, biomedical implants and grafts, or tissue and disease models.

This paper proposes an extension of the finite cell method (FCM) to V-rep models, a novel geometric framework for volumetric representations. This combination of an embedded domain approach (FCM) and a new modeling framework (V-rep) forms the basis for an efficient and accurate simulation of mechanical artifacts, which are not only characterized by complex shapes but also by their non-standard interior structure. These types of objects gain more and more interest in the context of the new design opportunities opened by additive manufacturing, in particular when graded or micro-structured material is applied. Two different types of functionally graded materials (FGM) are considered: The first one, multi-material FGM is described using the inherent property of V-rep models to assign different properties throughout the interior of a domain. The second, single-material FGM—which is heterogeneously micro-structured—characterizes the effective material behavior of representative volume elements by homogenization and performs large-scale simulations using the embedded domain approach.

Accelerating the designing and manufacturing of complex shapes has been a driving factor of modern industrialization. This has led to numerous advances in computational design and modeling and novel additive manufacturing (AM) techniques that can generate and fabricate complex shapes for bespoke applications. By combining new new coding-based design approach with advanced AM techniques for high-throughput fabrication, we envision a new approach to transform the way we design and fabricate complex shapes. Here, we demonstrate an algorithmic voxel-based approach, which can rapidly generate and analyze porous structures, auxetic meshes and cylinders, or perfusable constructs. We use this design scheme in conjunction with new approaches for multi-material volumetric printing based on thiol-ene photoclick chemistry to rapidly fabricate complex heterogeneous structures. Collectively, the new design and fabrication technique we demonstrate can be used across a wide-spectrum of products such as actuators, biomedical implants and grafts, or tissue and disease models.

Lattice components manufactured by selective laser melting processes are increasingly employed for producing high performing lightweight parts to be used in several industrial applications. However, the geometry at a submillimeter scale can exhibit not negligible differences with respect to the nominal design due to the high complexity of the manufacturing process. Accordingly, the mechanical behavior of lattice structures is strongly influenced by such process‐induced geometrical defects. Therefore, to numerically predict the fatigue behavior of lattice components, the as‐built geometry, as acquired, for instance, by means of micro‐computed tomography, should be considered. In this work, we employ an immersed boundary method, namely, the finite cell method, to develop a numerical framework suitable to compute fatigue life directly on an as‐built lattice geometry.