Abstract In this paper, nanoindentation on graphene/nickel nanocomposites with a three-dimensional “brick-and-mortar” structure is studied by molecular dynamics (MD) simulation method. The effects of various geometrical variations on mechanical properties are investigated, including the length of graphene layer, the interlayer distance of two adjacent graphene layers, and the lateral gap size of adjacent graphene in each layer. The simulation results show that the addition of graphene sheets can effectively block the dislocation propagation. The strength and hardness of the bio-inspired nanocomposites decrease with the increase of the length of graphene layers, while the increase in the length of the graphene layer can avoid dislocations nucleation at the end of the graphene sheet. As the lateral gap of graphene increases, the strength of the material decreases, and dislocations are easier to pass through the gap. In the absence of defects, as the lateral gap increases, the strength becomes larger, and the hardness is not obviously affected. This result is expected to be helpful for the preparation of graphene/metal nanocomposites with extremely enhanced mechanical properties.

中文翻译：

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仿生石墨烯/镍纳米复合材料的纳米压痕：分子动力学模拟

摘要 本文采用分子动力学（MD）模拟方法研究了具有三维“实体”结构的石墨烯/镍纳米复合材料的纳米压痕。研究了各种几何变化对机械性能的影响，包括石墨烯层的长度、两个相邻石墨烯层的层间距离以及每层中相邻石墨烯的横向间隙大小。仿真结果表明，石墨烯片的加入可以有效阻断位错传播。仿生纳米复合材料的强度和硬度随着石墨烯层长度的增加而降低，而石墨烯层长度的增加可以避免石墨烯片末端位错成核。随着石墨烯横向间隙的增加，材料强度降低，位错更容易通过间隙。在没有缺陷的情况下，随着横向间隙的增大，强度变大，对硬度影响不明显。该结果有望有助于制备具有极强机械性能的石墨烯/金属纳米复合材料。