The design of lattice structures with exceptional mechanical performance has been accentuated by recent advances in both additive manufacturing and mechanical modeling. Although there is a plethora of different lattice structures with intriguing properties, such as auxeticity and reciprocity, an exceptional class of lattice geometries is that of intertwined lattices, designed by the tactical coalition of polyhedral structures. Although the superior mechanical performance of the latter structures has been demonstrated at the microscale, their mechanical analysis is still incipient. In this study, the design principles and mechanical performance of such three-dimensional structures were examined at the macroscale and juxtaposed with their microscale counterparts. As a proof of concept, the first stellation of the rhombic dodecahedron, an ultralight/ultrastiff architected structure with superior stiffness and strain hardening characteristics, was examined both numerically and experimentally. Finite element analysis showed that intertwining greatly enhances both the stiffness and isotropic behavior of the structure. In addition, mechanical testing of both microscale and macroscale structures revealed that lattice intertwining leads to commensurate stiffness and strain energy density compared to that of the bulk material, even for 20% relative density. The findings of this study pave the way for a systematic and rigorous approach to design and modeling of macroscopic intertwined geometries, for comparing them with their microscopic equivalents, and for providing insight into scale effects on the mechanical performance of architected materials with intertwined lattices.

增材制造和机械建模方面的最新进展突显了具有出色机械性能的晶格结构设计。尽管存在许多具有吸引人的特性（例如，膨胀性和互易性）的不同晶格结构，但特殊的晶格几何类型是交织的晶格，它是由多面体结构的战术联盟设计的。尽管已经在微观上证明了后一种结构的优异机械性能，但它们的机械分析仍处于初期阶段。在这项研究中，这种三维结构的设计原理和机械性能在宏观上进行了检验，并与微观结构并列。作为概念的证明，菱形十二面体的第一颗星 通过数值和实验研究了具有超强刚度和应变硬化特性的超轻/超硬建筑结构。有限元分析表明，缠结大大增强了结构的刚度和各向同性行为。此外，对微观结构和宏观结构的机械测试都表明，即使相对密度为20％，晶格缠结也可以使刚性和应变能密度与块状材料相称。这项研究的发现为系统化和严格的方法设计和建模宏观交织的几何结构，将它们与微观等效结构进行比较铺平了道路，并提供了对交织网格的建筑材料的机械性能的尺度效应的见解。