Nano Lett. 2018 Aug 8;18(8):4845-4853. doi: 10.1021/acs.nanolett.8b01431. Epub 2018 Jul 9.
The mechanics of triply periodic minimal surfaces (TPMSs) with three-dimensional (3D) graphene foams are systematically studied to understand the effects of structure and size on the mechanical properties, for example, elasticity, strength, and fracture. The design of lightweight open-shell porous solid materials with TPMSs has shown excellent and tunable load-bearing properties. However, fracture properties and their relations with surface topologies are largely unknown. Utilizing reactive molecular dynamics simulations, here we investigate the elastic and fracture properties of three different surface topologies with 3D graphene foams: P (primitive), D (diamond), and G (gyroid), called Schwarzites. Models with different lattice sizes are utilized to derive power laws, which can connect the properties along different sizes to shed light on the multiscale mechanics of TPMSs. Our study provides a systematic understanding of the relation between TPMS topologies and their mechanical properties, including failure mechanisms of graphene foams, opening opportunities to explore designable structures with tailored properties.
本文系统地研究了具有三维（3D）石墨烯泡沫的三重周期性极小曲面（TPMS）的力学性能，以了解结构和尺寸对弹性、强度和断裂等机械性能的影响。TPMS 的设计为具有轻质开放式壳多孔固体材料提供了优异且可调的承载性能。然而，断裂性能及其与表面拓扑结构的关系在很大程度上尚不清楚。本文利用反应分子动力学模拟，研究了具有 3D 石墨烯泡沫的三种不同表面拓扑结构（P、D 和 G，称为 Schwarzites）的弹性和断裂性能。利用不同晶格尺寸的模型推导出幂律关系，将不同尺寸的性质联系起来，为 TPMS 的多尺度力学提供了启示。本研究提供了对 TPMS 拓扑结构与其力学性能之间关系的系统理解，包括石墨烯泡沫的失效机制，为探索具有定制性能的可设计结构开辟了机会。
