The mechanical property and micro-mechanism of nanoparticle-contained graphene foam materials under uniaxial tension

Nanoparticle-contained graphene foams (NP-GrFs) have been widely concerned and used in many practical applications in recent years. However, the mechanical property and its micro-mechanism of such a new composite material are still poorly understood. In this work, a coarse-grained NP-GrFs model is established to systematically study the mechanical response of NP-GrFs under uniaxial tension as well as the size and volume fraction effects of nanoparticles. It is found that both the initial modulus and tensile strength depend on the size and volume fraction of NPs, both of which can increase by almost an order of magnitude. Furthermore, when the volume fraction of nanoparticles increases, the strain hardening phenomenon occurs. Two main enhancing mechanisms are found. One is the increased adhesion between neighbor sheets by NPs and the other is the homogenized stress due to the extrusion of NPs. The present results should be useful not only for understanding the microstructure-determined mechanical properties of NP-GrFs but also for the design of advanced functional materials or devices based on GrFs.