氟等离子体对石墨烯纳晶碳膜的刻蚀加工及摩擦学性能调控  

Tribological Behavior Regulation of Graphene Nanocrystallites Embedded Carbon Film by Fluorine Plasma Etching

作　　者：郭美玲 杨雷 李鹏阳[1] 许振涛 许超愿 王权岱[1] 李言[1] GUO Meiling;YANG Lei;LI Pengyang;XU Zhentao;XU Chaoyuan;WANG Quandai;LI Yan(School of Mechanical and Precision Instrument Engineering,Xi’an University of Technology,Xi’an 710048;Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System,Xi’an Jiaotong University,Xi’an 710049)

机构地区：[1]西安理工大学机械与精密仪器工程学院,西安710048 [2]西安交通大学现代设计及转子轴承系统教育部重点实验室,西安710049

出　　处：《机械工程学报》2024年第15期216-226,共11页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51905423、52275210、52075439);西安市碑林区应用技术研发储备工程(GX2337)资助项目。

摘　　要：针对石墨烯低摩擦特性在宏观应用中存在的机械强度低、磨损寿命短等问题,提出采用氟等离子体刻蚀加工调控石墨烯纳晶碳膜以提升其摩擦学性能。通过表征刻蚀加工对碳膜形貌和结构的影响,提出氟等离子体刻蚀加工机理包括原子去除和离子注入两方面。一方面刻蚀加工可通过物理轰击或发生化学反应去除碳膜表面原子,有效降低碳膜表面粗糙度。另一方面刻蚀加工可通过亚表面注入使碳膜表层结构重组,sp3键含量增加,氟原子含量增加。通过测试刻蚀加工对碳膜性能的影响,发现刻蚀后碳膜表层引入的氟原子使其表面悬键钝化、表面能降低,表层sp3键含量的增加使碳膜的硬度提高。最终相比石墨烯纳晶碳膜,刻蚀重构碳膜展现出优异的摩擦学性能:当法向载荷为2 N时,摩擦因数从0.22降低至0.08,磨损寿命从120圈增加至大于15000圈。并分析得到摩擦学性能提升原因在于表面粗糙度的显著降低、表面悬键钝化和机械性能的提升。In macroscopic tribological applications,graphene-based carbon films exhibit low friction coefficient but weak mechanical strength and short wear life.Aimed at these problems,a fluorine plasma etching technology is proposed to promote the tribological property of a graphene nanocrystallites embedded carbon(GNEC)film.By characterizing the influences of the fluorine plasma etching on the morphology and structure of the GNEC film,it is found that the etching has two functions:atom removal and ion implantation.On the one hand,the etching can remove the carbon atoms in surface asperities through physical bombardment or chemical reaction to effectively reduce the film surface roughness.On the other hand,the etching induced subplantation can restructure the film top-surface to make its sp3 bonds and fluorine atoms increase.Then the effects of the fluorine plasma etching on the film properties are measured.The results show that after the etching,the film surface energy decreases because the introduced fluorine atoms would passivate the dangling bonds on the film surface,and the film hardness is enhanced due to the increased sp3 bonds.Therefore,compared with the GNEC film,the restructured film after the fluorine plasma etching exhibits the excellent tribological property.Under the normal load of 2 N,the friction coefficient decreases from 0.22 to 0.08,and the wear life increases from 120 cycles to more than 15000 cycles.The reasons for the improved tribological property after the fluorine plasma etching are the reduced surface roughness,the passivation of surface dangling bonds,and the enhanced mechanical property.

关 键 词：氟等离子体刻蚀 石墨烯基碳膜 表层结构重组 表面悬键钝化 摩擦磨损性能 

分 类 号：TH117[机械工程—机械设计及理论]