为了深入探讨硅探针在石墨烯台阶边缘的摩擦力变化特性及其微观摩擦机制，利用分子动力学方法建立模型，重点研究了不同的台阶层数、正压力作用下摩擦力变化规律，并利用x和z方向的应变云图分析摩擦特性.结果表明：正压力对石墨烯台阶边缘的摩擦力变化特性的影响不大，但台阶层数对石墨烯台阶边缘的摩擦力变化特性将产生较大影响；在压头爬上台阶的过程中，出现了明显挤压应力聚集的现象，在压头爬上多层台阶的过程中还伴随着挤压应力的释放；x方向的挤压应变以及z方向压坑中心圆的完整度是衡量摩擦力的重要指标
In order to further investigate the frictional force characteristics of the silicon probing at the edge of graphene and its microscopic friction mechanism, a model was established by using molecular dynamics method, focusing on the variation of frictional force under different levels and positive pressure. The friction characteristics were also analyzed by using the strain cloud in the x and z directions. The results show that the positive pressure has little effect on the frictional characteristics of the graded edge of graphene, but the change of the number of steps will have a great influence on the frictional characteristics. In the process of pressing on the step, the phenomenon of compressive stress accumulation is accompanied by the release of compressive stress in the process of multi-step climbing. The compressive strain in the x direction and the integrity of the center of the crater in the z direction are important indexes to measure the friction force.
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