宽温域环境中聚四氟乙烯及其复合材料摩擦学性能研究  

Tribological Performance of PTFE and Its Composite in Wide Temperature Range

作　　者：齐慧敏 胡超 李洁[1] 黄朝洋 周逸 崔俊楠 余家欣[1] 张嘎[2] QI Huimin;HU Chao;LI Jie;HUANG Chaoyang;ZHOU Yi;CUI Junnan;YU Jiaxin;ZHANG Ga(Key Laboratory of Manufacturing Process Testing Technology Ministry of Education,Southwest University of Science and Technology,Sichuan Mianyang 621010,China;State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Gansu Lanzhou 730000,China;State Key Laboratory of Tribology,Tsinghua University,Beijing 100084,China)

机构地区：[1]西南科技大学制造过程与测试技术教育部重点实验室,四川绵阳621010 [2]中国科学院兰州化学物理研究所固体润滑国家重点实验室,甘肃兰州730000 [3]清华大学摩擦学国家重点实验室,北京100084

出　　处：《摩擦学学报》2022年第1期65-73,共9页Tribology

基　　金：中国科学院兰州化学物理所固体润滑国家重点实验室开放课题(20zd3112);清华大学摩擦学国家重点实验室开放课题(20zd3120);西南科技大学博士基金(18zx7162);四川省科技厅重大前沿科学技术研究面上项目(2018JY0245)资助。

摘　　要：对比研究了−100~100℃范围内聚四氟乙烯(PTFE)及三氧化二铝/聚四氟乙烯(Al_(2)O_(3)/PTFE)复合材料的摩擦学性能.研究结果表明,PTFE因为蠕变,在升温过程中摩擦系数逐步降低,磨损率逐步升高.而引入Al_(2)O_(3)填料会显著影响PTFE的摩擦学行为,Al_(2)O_(3)/PTFE的摩擦系数普遍比PTFE高,而磨损率比PTFE低.摩擦学机理表明,滑动过程中形成的摩擦膜是决定摩擦学行为的关键因素.这对极端工况条件下高分子复合材料的设计具有重要的指导意义.In this paper,PTFE and Al_(2)O_(3)/PTFE composites were prepared by cold pressing and hot sintering technology.DSC characterization was performed to evaluate their thermal stability and the result showed that due to the high inert of Al_(2)O_(3),the crystal structure of PTFE was not changed and little effect on the thermal properties of PTFE was observed.Moreover,the tribological properties of PTFE and Al_(2)O_(3)/PTFE composites in temperature range from-100 to 100℃ were studied,and micro/nano tribological performance of PTFE and Al_(2)O_(3)/PTFE were compared at room temperature.Tribological results showed that the lowest friction coefficient of PTFE was 0.15 at 100℃,while its lowest wear rate was 1.0×10^(-6)mm^(3)/(N·m)at -100℃.After 25℃,the wear rate increased sharply and reached the maximum value of 1.0×10^(-3)mm^(3)/(N·m)at 50℃.With the increasing of temperature,the interlaminar energy of PTFE increased,which made it easier to produce creep by sliding shear,so that the friction coefficient of PTFE decreased and the wear rate increased gradually.The incorporation of Al_(2)O_(3)significantly affected the tribological behavior of PTFE.Above 25℃,the friction coefficient of Al_(2)O_(3)/PTFE was higher than that of PTFE,while the wear rate was lower than that of PTFE.The friction coefficient of Al_(2)O_(3)/PTFE reached the maximum value of 0.51 at -50℃,and then decreased gradually with the increase of temperature,and reached the minimum value of 0.22 at 100℃.It was assumed that PTFE was frozen at -100℃ and a small amount of Al_(2)O_(3)was released to act as lubricant,which made the friction coefficient of Al_(2)O_(3)/PTFE lower than that of PTFE.With the increase of temperature,more and more Al_(2)O_(3)nanoparticles were released,and the aggregation of large particles was not conducive to the lubrication,so the friction coefficient was larger than that of pure PTFE.With regard to the wear rate,the lowest of wear rate Al_(2)O_(3)/PTFE was observed at -100℃ and the highest was obtained at 50

关 键 词：PTFE Al_(2)O_(3) 高温 低温 摩擦膜 

分 类 号：TH117.3[机械工程—机械设计及理论]