Multilayered graphitic materials are not suitable as load-bearers due to their inherent weak interlayer bonding (for example, graphite is a solid lubricant in certain applications). This situation is largely improved when two-dimensional (2-D) materials such as a monolayer (SLG) graphene are employed. The downside in these cases is the presence of thermally or mechanically induced wrinkles which are ubiquitous in 2-D materials. Here we set out to examine the effect of extensive large wavelength/ amplitude wrinkling on the stress transfer capabilities of exfoliated simply-supported graphene flakes. Contrary to common belief we present clear evidence that this type of "corrugation" enhances the load bearing capacity of few-layer graphene as compared to 'flat' specimens. This effect is the result of the significant increase of the graphene/polymer interfacial shear stress per increment of applied strain due to wrinkling and paves the way for designing affordable graphene composites with highly improved stress-transfer efficiency.
翻译:多层石墨材料由于其内在的低强度层间结合(例如,石墨在某些应用中是一种固体润滑剂),不适合作为载荷承载器。当使用单层石墨等二维(2-D)材料时,这种情况大为改善。这些情况下的下坡是热或机械引引的皱纹,在2D材料中普遍存在。我们在这里研究大量大波长/振动波纹对挥发的简单支持的石墨片的压力转移能力的影响。与我们的共同看法相反,我们提出明确的证据表明,这种“冲压”可提高单层石墨与“膨胀”标本相比的载荷能力。这种效应是石墨/聚合双壁壳在2D材料中因皱纹而使施压强度增加的显著增加的结果,并铺平了设计可负担的石墨复合材料的途径,从而大大提高了压力转移效率。