Multiscale Mechanics of Triply Periodic Minimal Surfaces of Three-Dimensional Graphene Foams

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.