Abstract The aim of this work is to deliver a precise statement about the mechanical effect of microstructural defects induced by stereolithography. Design of cellular structures based on a photosensitive resin with varied porosity content is performed up to 60%. The compressive behaviour of these structures is captured and microstructural defects are analysed using X-ray micro-tomography. Finite element computation is considered to predict the compressive behaviour of both 3D microstructures and CAD (Computer-Aided Design) models up to the densification stage. X-ray micro-tomography analyses reveals that two main defects are generated by the process, namely residual support material and excess of resin trapped inside the porous network. Significance of the defects is proved to be related to the design of cellular structures with porosity levels in the range 10–30%. In addition, both experimental and numerical results show no evidence of anisotropic effect related to additive layering of resin. Finally, the suggested damage – densification constitutive law captures the main characteristics of the compressive response of studied cellular structures.

中文翻译：

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使用立体光刻设计的聚合物蜂窝结构的微观结构和机械性能分析

摘要 这项工作的目的是提供关于立体光刻引起的微观结构缺陷的机械效应的精确陈述。基于光敏树脂的多孔结构设计具有不同的孔隙率，最高可达 60%。捕获这些结构的压缩行为并使用 X 射线显微断层扫描分析显微结构缺陷。有限元计算被认为可以预测 3D 微观结构和 CAD（计算机辅助设计）模型直到致密化阶段的压缩行为。X 射线显微断层扫描分析表明，该过程会产生两个主要缺陷，即残留的支撑材料和困在多孔网络内的过量树脂。已证明缺陷的重要性与孔隙率在 10-30% 范围内的蜂窝结构的设计有关。此外，实验和数值结果均未显示与树脂添加剂分层相关的各向异性效应的证据。最后，建议的损伤-致密化本构法则捕捉了所研究细胞结构的压缩响应的主要特征。