This study aims to fabricate complex ceramic tetrahedron structures, which are challenging to produce by more conventional methods such as injection molding. To achieve this aim, thermoplastic-ceramic composite filaments were developed and printed with unmodified, consumer-grade, fused deposition modelling (FDM) printers instead.,Al2O3 ceramic powder was mixed with ethylene vinyl acetate polymer as a binder (50 Vol.- per cent) to form a filament with a constant diameter of 1.75 mm. After the printing and thermal treatment stages, the shrinkage and mechanical properties of cuboid and tetrahedron structures were investigated.,The shrinkage of the parts was found to be anisotropic, depending on the orientation of the printing pattern, with an increase of 2.4 per cent in the (vertical) printing direction compared to the (horizontal) printing layer direction. The alignment of the ceramic particle orientations introduced by FDM printing was identified as a potential cause of the anisotropy. This study further demonstrates that using a powder bed during the thermal debinding process yields sintered structures that can withstand twice the compressive force.,Ceramic FDM had previously been used primarily for simple scaffold structures. In this study, the applicability of ceramic FDM was extended from simple scaffolds to more complex geometries such as hollow tetrahedra. The structures produced in this study contain dense parts printed from multiple contiguous layers, as compared to the open structures usually found in scaffolds. The mechanical properties of the complex ceramic parts made by using this FDM technique were also subjected to investigation.

中文翻译：

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使用消费级熔融沉积模型打印机制造复杂的 Al2O3 陶瓷结构

这项研究旨在制造复杂的陶瓷四面体结构，这些结构通过注射成型等更传统的方法难以生产。为了实现这一目标，开发了热塑性陶瓷复合长丝，并使用未改性的消费级熔融沉积成型 (FDM) 打印机进行打印。Al2O3 陶瓷粉末与作为粘合剂的乙烯醋酸乙烯酯聚合物混合（50 卷cent) 形成直径恒定为 1.75 mm 的长丝。在印刷和热处理阶段之后，研究了长方体和四面体结构的收缩和机械性能。发现零件的收缩是各向异性的，取决于印刷图案的方向，增加了 2。与（水平）印刷层方向相比，（垂直）印刷方向的 4%。FDM 印刷引入的陶瓷颗粒取向的排列被确定为各向异性的潜在原因。这项研究进一步证明，在热脱脂过程中使用粉末床产生的烧结结构可以承受两倍的压缩力。陶瓷 FDM 以前主要用于简单的支架结构。在这项研究中，陶瓷 FDM 的适用性从简单的支架扩展到更复杂的几何形状，如空心四面体。与通常在支架中发现的开放结构相比，本研究中产生的结构包含从多个连续层打印的致密部分。