摘要
聚酰亚胺(polyimide,简称PI)分子主链中含有稳定的芳杂环结构,在高温状态下表现出较好的机械强度和耐磨性。针对空间超声电机对长寿命摩擦材料的需求,在纤维增强和纳米改性的基础上,研究二硫化钼含量对PI材料摩擦磨损性能的影响规律。首先,测试干摩擦条件下不同含量二硫化钼对PI复合材料摩擦磨损性能的影响;其次,通过扫描电子显微镜观察复合材料磨损表面,揭示材料的损伤机制以及转移膜的形成过程;最后,优选磨损率最低的PI复合材料,对超声电机摩擦材料进行加速寿命试验,将摩擦材料切片粘贴在定子磷青铜表面,配副为微弧氧化后铝合金转子,验证该材料在超声电机中应用的可行性。结果表明:随着二硫化钼含量的增加,复合材料的摩擦因数和磨损率均有明显下降。使用新型摩擦材料的TRUM-60型电机经过552 h磨合后,摩擦材料深度仅下降40.28μm,占材料总厚度的4.03%,电机输出机械特性依旧保持稳定。
Polyimide(PI)molecules contain stable aromatic heterocyclic structures in their main chains,exhibiting good mechanical strength and wear resistance at high temperatures.To address the demand for long-life friction material in space ultrasonic motors,the influences of molybdenum disulfide(MoS2)content on the tribological properties of PI composites based on fiber reinforcement and nano-modification is systematically investigated.First,the tribological properties of PI composites with different MoS2 contents are measured.Second,the worn surface of the composites is observed using scanning electron microscopy to reveal the damage mechanisms and the formation process of the transfer film.Finally,the PI composites with the lowest wear rate are selected as the friction material for the ultrasonic motor,which is matched with aluminum alloy rotor treated with micro-arc oxidation to verify its feasibility in an ultrasonic motor.The results show that the friction coefficient and wear rate of the composites decrease significantly with increasing MoS2 content.For a TRUM-60 motor using the new friction material,after 552 hours of run-in,the thickness of frictional material decreases by only 40.28μm,representing 4.03%of its total thickness,and the output mechanical properties remain stable.
作者
曹鑫鑫
赵盖
李兴明
丁庆军
CAO Xinxin;ZHAO Gai;LI Xingming;DING Qingjun(State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics Nanjing,210016,China;State Key Laboratory of Solid Lubrication of Lanzhou Institute of Chemical Physics,Chinese Academy of SciencesLanzhou,730000,China)
出处
《振动.测试与诊断》
北大核心
2025年第4期791-796,849,共7页
Journal of Vibration,Measurement & Diagnosis
基金
国家自然科学基金资助项目(52075247,U2037603)
中央高校基本科研业务费资助项目(NS2022016)
南京航空航天大学研究生科研与实践科研创新计划资助项目(xcxjh20210110)。
关键词
聚酰亚胺
摩擦磨损
二硫化钼
转移膜
超声电机
polyimide
friction and wear
molybdenum disulfide
transfer film
ultrasonic motor
