Lattice structures are lightweight and are known to exhibit excellent energy absorbing capability when subject to compressive loading. In this paper, a new analytical model for the stiffness, strength, and energy absorption of additively manufactured functionally graded lattice structures is presented, leading to the establishment of a new energy absorption optimisation approach. The influence of cell orientation, cell aspect ratio, and cell relative density on the mechanical properties is characterised. The optimal through-thickness density distribution to maximise energy absorption is determined, subject to mass and initial stiffness constraints. Energy absorption is shown experimentally to increase by up to 67.1 % via tailored through-thickness grading of the structure's relative density. Finite element models are also developed to accurately describe the mechanical performance of these functionally graded lattice structures. These models provide valuable insight into the properties of functionally graded lattice structures and can serve as a basis for the tailored design of lightweight energy absorbers.

中文翻译：

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功能梯度的晶格结构，具有定制的刚度和能量吸收


晶格结构重量轻，在承受压缩载荷时表现出优异的能量吸收能力。在本文中，提出了一种新的分析模型，用于增材制造的功能梯度晶格结构的刚度、强度和能量吸收，从而建立了一种新的能量吸收优化方法。表征了单元方向、单元纵横比和单元相对密度对机械性能的影响。根据质量和初始刚度约束，确定最佳全厚度密度分布以最大限度地提高能量吸收。实验表明，通过对结构相对密度进行量身定制的全厚度分级，能量吸收最多可增加 67.1%。还开发了有限元模型来准确描述这些功能梯度晶格结构的机械性能。这些模型为功能梯度晶格结构的特性提供了有价值的见解，可以作为轻型能量吸收器定制设计的基础。