碳纤维改性聚四氟乙烯的摩擦及振动性能

Friction and Vibration Properties of Carbon Fiber Modified Polytetrafluoroethylene

文中研究了20%的碳纤维(体积分数)改性聚四氟乙烯在干摩擦和水润滑摩擦条件下的摩擦系数、磨损性能和摩擦振动性能。结果表明:(1)在干摩擦下,随着线速度增加,摩擦界面生成大量的热,黏着磨损和磨粒磨损严重,表面越来越粗糙,摩擦系数明显变大,摩擦振动加速度增加。而在水润滑条件下,随着线速度增加,摩擦界面间形成了一层水润滑膜,使摩擦系数降低,另外由于转速增加,使流噪声增加,从而使振动增加。(2)在干摩擦下,随着比压增加,摩擦系数和摩擦振动变化较大,而在水润滑条件下,随着比压增加,摩擦系数和摩擦振动变化较小。(3)干摩擦时,碳纤维增强聚四氟乙烯复合材料在不同比压下的磨损机理主要是磨粒磨损和黏着磨损;水润滑条件下,碳纤维增强聚四氟乙烯复合材料在高比压下的磨损机理主要是黏着磨损。因此,碳纤维改性聚四氟乙烯复合材料应该在水润滑条件下应用有利于提高耐磨性,降低摩擦系数和摩擦振动。

In this paper,the coefficient of friction(COF),wear performance and friction vibration performance of 20%(volume fraction)carbon fiber modified polytetrafluoroethylene(CF-PTFE)under dry friction and water lubricated friction conditions are studied.Results show:(1)Under dry friction,as the sliding linear velocity increases,a large amount of heat is generated at the friction interface,adhesive wear and abrasive wear are serious,the surface becomes rougher,the COF becomes significantly larger,and the frictional vibration acceleration increases.Under water lubricated conditions,as the linear velocity increases,a water lubrication film is formed between the friction interfaces,which reduces the COF.In addition,due to the increase in speed,the flow noise increases,thereby increasing the vibration.(2)Under dry friction,as the specific pressure increases,the COF and frictional vibration change greatly.While under water lubrication conditions,the COF and frictional vibration change less as the specific pressure increases.(3)During dry friction,the wear mechanism of CF-PTFE composites under different specific pressures is mainly abrasive wear and adhesive wear;under water lubricated conditions,the main wear mechanism of CF-PTFE composites under high specific pressures is adhesive wear.Therefore,the application of carbon fiber is beneficial to improve wear resistance of PTFE under water lubricated conditions,reducing COF and frictional vibration.This research provides a certain technological method for the application of CF-PTFE in frictional moving parts.