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additional research challenges, namely in their depo sition, conversion, and interfaces. The opportunity for AM more generally has been determined by its functionality over more traditional manufacturing methods; where geometrical complexity is an inherent strength. The realization of mul tifunctional AM (MFAM) could augment this opportunity through the processing of multiple materials to gain further com ponent function in the final part. [7][8][9][10][11][12] Pre vious work in multiple material deposition has focused on the grading of materials to enhance physical, mechanical, and bio logical charac teristics. [4,5,13] However, the concurrent deposition of dissimilar mate rials is in its infancy, due in the main to the disparate materials processing require ments for metals, polymers, and ceramics.In general the 3D printing of electronic structures is dominated by the conformal printing of conductive materials onto the surface of a dielectric structure (otherwise known as Direct Write), [14][15][16][17][18] or the embed ment of conductive elements within previously 3Dprinted dielec tric materials. [19][20][21][22] Other reports have demonstrated the printing of conductive, semiconductive and dielectric materials in a single component, but these were limited to a small number of layers (<10 layers) and hence vertical heights of a few 100 µm, limiting the aspect ratio of these 3D conductive structures. [20,[23][24][25][26] A com mercial product, Voxel 8, was recently launched to extrude con ductive pastes and thermal plastics in a single 3D printing appa ratus. [27] This approach shows that the 3D printing of functional tracks is possible but the method is often limited by the low spatial resolution of the process being used (e.g., extrusionbased AM).Recently, inkjet printing has been used for the deposition of a wide range of functional inks with a diverse spectrum of prop erties. [26,[28][29][30][31][32] The fact that inks are ejected from print heads with a large number of small nozzles offers scalability through a droplet on demand (DoD) regime, one that is commonly ena bled through piezoelectric inkjet print technology. This regime is key to enable the deposition of different materials alongside each other, required for MFAM. DoD inkjet printing has been reported as a tool for multimaterial fabrication due to the flex ibility of the technology to dynamically adapt different patterns and materials in contrast to other printing and manufacturing technologies that require fixed mask or tooling. DoD tech nology is being applied in a diverse portfolio of applications, for example in biology, tissue bioprinting, multienzyme inkjet printing, and various types of cell printing have been recently reported. [13,[33][34][35][36] In electronics, a wide range of inkjetprinted applications have been demonstrated, ranging from inkjet printing of passive components, [37][38][39][40] active components (e.g.,The production of electronic circuits and devices is limited by current manufacturing methods that limit both the form...

Selective laser melting (SLM) has previously been shown to be a viable method for fabricating biomedical implants; however, the surface chemistry of SLM fabricated parts is poorly understood. In this study, X-ray photoelectron spectroscopy (XPS) was used to determine the surface chemistries of (a) SLM as-fabricated (SLM-AF) Ti6Al4V and (b) SLM fabricated and mechanically polished (SLM-MP) Ti6Al4V samples and compared with (c) traditionally manufactured (forged) and mechanically polished Ti6Al4V samples. The SLM-AF surface was observed to be porous with an average surface roughness (Ra) of 17.6±3.7μm. The surface chemistry of the SLM-AF was significantly different to the FGD-MP surface with respect to elemental distribution and their existence on the outermost surface. Sintered particles on the SLM-AF surface were observed to affect depth profiling of the sample due to a shadowing effect during argon ion sputtering. Surface heterogeneity was observed for all three surfaces; however, vanadium was witnessed only on the mechanically polished (SLM-MP and FGD-MP) surfaces. The direct and indirect 3T3 cell cytotoxicity studies revealed that the cells were viable on the SLM fabricated Ti6Al4V parts. The varied surface chemistry of the SLM-AF and SLM-MP did not influence the cell behaviour.

The fabrication of tissue engineering scaffolds based on the polymerization of crosslinked polylactide using leaching and batch foaming to generate well‐controlled and interconnected biodegradable polymer scaffolds is reported. The scaffold fabrication parameters are studied in relation to the interpore connectivity, pore morphology, and structural stability of the crosslinked PLA scaffold. In vitro cell culture and in vitro degradation are used to analyze the biocompatibility and biodegradability of the scaffolds. The new crosslinked PLA thermoset scaffolds are highly suitable for bone tissue engineering applications due to their complex internal architecture, thermal stability, and biocompatibility. magnified image