Abstract With respect to the inherent poor tribological behavior of aluminum (Al), reinforcement of this metal with nanoscale fillers is a promising research area with significant industrial impact. Accordingly, in the current research, we have probed the tribological characteristics of Al-based nanocomposites embedded with nanofillers of different geometries. Targeting this purpose, a series of nanoscratching tests based on molecular-dynamics simulations is carried out to explore the effect of spherical silicon carbide nanoparticles and graphene monolayers on the coefficient of friction (COF) of the baseline Al matrix. The results reveal that while the former inclusion reduces this parameter, COF is enhanced in the presence of platelet graphene sheets. To find out the underlying mechanism, the microstructural evolutions are thoroughly examined in the interfacial area by means of the dislocation extraction analysis. Our findings are supported by an in-depth study on the pile-up features and more pronounced plastic deformation zones in the samples. Furthermore, to overcome the deteriorating influence of graphene on the COF of the Al matrix, various composite systems are designed which differ in the depth where the nanofiller was positioned. Finally, a solution is presented to increase the mechanical performance of the Al-based nanocomposites in the presence of graphene sheets without sacrificing their tribological behavior.

中文翻译：

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纳米填料的几何方面影响铝基纳米复合材料的摩擦学性能

摘要 针对铝 (Al) 固有的较差摩擦学行为，用纳米级填料增强这种金属是一个具有重大工业影响的有前途的研究领域。因此，在目前的研究中，我们探索了嵌入不同几何形状的纳米填料的铝基纳米复合材料的摩擦学特性。针对此目的，进行了一系列基于分子动力学模拟的纳米划痕测试，以探索球形碳化硅纳米颗粒和石墨烯单层对基线 Al 基体摩擦系数 (COF) 的影响。结果表明，虽然前一种内含物降低了该参数，但在存在片状石墨烯片的情况下，COF 增强。为了找出潜在的机制，通过位错提取分析，彻底检查了界面区域的微观结构演变。我们的发现得到了对样品中堆积特征和更明显塑性变形区的深入研究的支持。此外，为了克服石墨烯对 Al 基体 COF 的恶化影响，设计了各种复合系统，它们的纳米填料所在的深度不同。最后，提出了一种在石墨烯片存在下提高铝基纳米复合材料机械性能而不牺牲其摩擦学行为的解决方案。此外，为了克服石墨烯对 Al 基体 COF 的恶化影响，设计了各种复合系统，其纳米填料所处的深度不同。最后，提出了一种在石墨烯片存在下提高铝基纳米复合材料机械性能而不牺牲其摩擦学行为的解决方案。此外，为了克服石墨烯对 Al 基体 COF 的恶化影响，设计了各种复合系统，它们的纳米填料所在的深度不同。最后，提出了一种在石墨烯片存在下提高铝基纳米复合材料机械性能而不牺牲其摩擦学行为的解决方案。