Fraunhofer Institute for Mechanics of Materials IWM , Wöhlerstraße 11, 79108 Freiburg, Germany.
Nano Lett. 2014 Dec 10;14(12):7145-52. doi: 10.1021/nl5037403. Epub 2014 Nov 11.
We study nanoindentation and scratching of graphene-covered Pt(111) surfaces in computer simulations and experiments. We find elastic response at low load, plastic deformation of Pt below the graphene at intermediate load, and eventual rupture of the graphene at high load. Friction remains low in the first two regimes, but jumps to values also found for bare Pt(111) surfaces upon graphene rupture. While graphene substantially enhances the load carrying capacity of the Pt substrate, the substrate's intrinsic hardness and friction are recovered upon graphene rupture.
我们通过计算机模拟和实验研究了覆盖有石墨烯的 Pt(111)表面的纳米压痕和划伤。我们发现，在低负载下表现出弹性响应，在中间负载下 Pt 在石墨烯下发生塑性变形，最终在高负载下石墨烯发生破裂。在前两个阶段，摩擦仍然很低，但在石墨烯破裂时，摩擦会跃升至与裸露的 Pt(111)表面相同的值。虽然石墨烯大大提高了 Pt 衬底的承载能力，但在石墨烯破裂后，衬底的固有硬度和摩擦会恢复。
