Abstract Distinguished capabilities of cellular solids as high-performance energy absorbers can be enhanced by engineering their underlying architectures. In this study, we classify different groups of lattices based on their topology and propose a strategy to enhance their energy absorption-to-weight ratio under compression. We particularly elucidate the effect of variation of relative density across the lattice structures that are 3D printed by stereolithography. The experimental compression test results and numerical data obtained by finite element analysis show that a uniform design with even distribution of relative density yields the highest initial stiffness among all 3D printed architected lattices. However, the graded design with a rational variation of relative density can significantly enhance the stiffness and energy absorption capability of lattices that are experiencing high compressive strains. Specific gradients, where the relative density varies normal to the direction of external compressive force, can increase the stiffness and the energy absorption capabilities of cellular solids up to 60 and 110%, respectively. These results promise the possibility of designing single-phase lattice architectures that can combine lightweighting and energy absorption properties by a rational variation of porosity within the cellular architecture.

中文翻译：

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渐变晶格结构：同时增强刚度和能量吸收

摘要 蜂窝固体作为高性能能量吸收器的独特能力可以通过对其底层结构进行工程设计来增强。在这项研究中，我们根据其拓扑结构对不同的晶格组进行分类，并提出了一种提高压缩下的能量吸收重量比的策略。我们特别阐明了通过立体光刻 3D 打印的晶格结构中相对密度变化的影响。通过有限元分析获得的实验压缩测试结果和数值数据表明，相对密度分布均匀的均匀设计在所有 3D 打印建筑晶格中产生最高的初始刚度。然而，相对密度合理变化的渐变设计可以显着提高承受高压缩应变的晶格的刚度和能量吸收能力。特定梯度，其中相对密度垂直于外部压缩力的方向变化，可以将多孔固体的刚度和能量吸收能力分别提高 60% 和 110%。这些结果保证了设计单相晶格结构的可能性，该结构可以通过蜂窝结构内孔隙率的合理变化来结合轻量化和能量吸收特性。可以将多孔固体的刚度和能量吸收能力分别提高 60% 和 110%。这些结果保证了设计单相晶格结构的可能性，该结构可以通过蜂窝结构内孔隙率的合理变化来结合轻量化和能量吸收特性。可以将多孔固体的刚度和能量吸收能力分别提高 60% 和 110%。这些结果保证了设计单相晶格结构的可能性，该结构可以通过蜂窝结构内孔隙率的合理变化来结合轻量化和能量吸收特性。