PTFE基超声电机摩擦材料磨合阶段摩擦磨损特性研究

在超声电机运行200 h时间内,对超声电机的运行参数进行监测,采用激光共聚焦显微镜对定、转子表面粗糙度、表面形貌和磨屑特征等进行观察分析,探讨超声电机磨合期的时间及磨合期、稳定期的摩擦磨损特性.结果表明:1经过80 h磨合后,超声电机性能基本稳定.2磨合初期,摩擦材料磨损形式以黏着磨损为主,在定子表面可观测到尺寸较大的片状磨屑,进入摩擦稳定期后摩擦材料表面出现大量点蚀凹坑,表面疲劳磨损成为磨损形式之一,磨粒磨损始终存在并占重要部分;定子表面可观测到明显犁沟,磨损形式以磨粒磨损为主.3由于超声振动的存在,摩擦产生的磨屑不易在摩擦表面停留,进入稳定期后在摩擦界面难以观测到磨屑的大量存在,超声振动有排除磨屑的作用.

Friction and Wear Properties of PTFE-Based Friction Material Used in Ultrasonic Motor during Running-in Stage

In 200 hours,the operating parameters of ultrasonic motor (USM) were monitored and surface roughness,surface morphology,debris characteristics of stator and rotor were observed and analyzed used laser scanning confocal microscope to discuss friction and wear properties of USM. The result show that after running for 80 h,the performance of USM became stable. In the early stage,adhesive wear was the main wear mechanism and there were many large lump debris on the surface of stator. In stable friction stage,there were many corrosive pitting on worn surface of friction material and a small amount of particulate wear debris can be observed on stator surface. Fatigue wear was one of wear mechanisms. Abrasive wear was always the important wear mechanism in this stage. Apparent ploughs can be seen on the stator surface,the wear mechanism was abrasive wear. Due to the ultrasonic vibration,wear debris was removed from the friction surface in stable wear stage and therefore it is hard to observe wear debris on the interface of stator and rotor. The ultrasonic vibrations had an effect of eliminating the debris from the friction surface.