石墨烯及其复合材料纳米力学研究进展

石墨烯是一种由碳原子构成的二维晶体,是目前已知最薄但却有着极高强度的纳米材料.由于在强度、导热性、电子输运和光学上显示出不同寻常的特性,石墨烯迅速成为材料科学、物理、化学和力学等学科的研究热点.与此同时,石墨烯复合材料的研究也迅速兴起.论文综述了近年来石墨烯及其复合材料的力学特性的研究进展.根据力学行为的差异,我们主要阐述了石墨烯面内力学特性、离面力学特性、原子尺度修饰和石墨烯复合材料力学特性的研究进展:石墨烯的面内拉伸力学特性通过纳米压痕等技术得到了测量,其断裂行为在微纳尺度下不能完全使用连续介质力学模型进行解释,在多层石墨烯情况下会出现超润滑现象;石墨烯的可控离面位移对于改变其物理特性有重要的意义,石墨烯上的屈曲受到手性和尺度的影响,在高频器件中存在着非连续性的离面响应;适当的原子尺度修饰可以改善石墨烯的拉伸和扭转力学特性;石墨烯可以改善复合材料的力学特性,如提高强度、韧性等,其主要强化效应是通过与基体材料的离面、面内力学行为结合产生的.最后,论文对石墨烯及其复合材料的力学研究进行了总结和展望.

Research progress in nanomechanics of graphene and its composites

Graphene is an allotrope of carbon in the form of a two-dimensional, atomic-scale, hexagonal lattice in which one atom forms each vertex, which is the known thinnest and strongest nanomaterial. Due to the excellent electronic, thermodynamical, optical and mechanical properties, graphene becomes a study hotspot in the fields of material science, physics, chemistry and mechanics. Derivatively, graphene composites have attracted tremendous research interest in recent years. According to the difference of mechanical behaviors, this review mainly presents and discusses the advances of graphene’s in-plane mechanical properties, out-of-plane mechanical properties, atomic revised graphene and graphene composites: the in-plane tension mechanical properties of graphene is measured via nanoindentation methods, the fracture of graphene is not completely consistent with continuum mechanical models, and the superlubricity occurs in multilayer-graphene; controllable out-of-plane displacement in graphene monolayer plays an important role in changing its physical properties, the buckling in graphene monolayer is influenced by its size and chirality, and there will be non-continuum effect in graphene-related devices with high frequency; graphene can improve the strength and toughness of composites, which is resulted through the combination of in-plane and out-of-plane interactions. Lastly, the summary and forecast of the mechanical study of graphene and graphene composites are narrated.