面向低温环境的聚合物摩擦学性能及其改性研究进展

Research Progress of Polymer Tribological Properties and Modification inLow Temperature Environment

聚合物及其复合材料具有力学性能好、摩擦系数低、耐磨性能强等优点,常被应用于制造摩擦副关键基础件,如密封圈、齿轮、轴承保持架、转子叶片、活塞等。但迄今针对低温工况的聚合物摩擦学研究甚少,主要工作集中在常温和高温工况。面向低温环境的聚合物及其复合材料的摩擦学应用与相关制备、改性工艺的相关理论并不完备,极端服役环境下聚合物的摩擦学损伤失效机理还尚未完全清楚。此外,聚合物材料虽然具有众多优良的性能,但是其表面硬度低、温度影响大、易变形等缺点也同样明显,限制了其在低温摩擦学领域的应用,为此,研究者通过填充填料、表面处理等方法对聚合物进行了改性研究,取得了一定的成果。目前,由于航空航天等前沿技术的不断发展,聚合物在真空低温环境下的摩擦学性能受到了广泛关注,聚四氟乙烯、聚酰亚胺、聚醚醚酮等聚合物自润滑材料已被应用于空间飞行器领域来制作润滑和密封部件。研究者利用石墨、石墨烯、二硫化钼、芳纶纤维、玻璃纤维等对聚合物进行改性,制备了在低温环境下具有低摩擦系数、高耐磨性的聚醚醚酮/石墨、聚四氟乙烯/芳纶纤维、聚四氟乙烯/超高分子量聚乙烯等复合材料,促进了聚合物在低温摩擦学领域的应用。本文系统分析了低温环境下温度、环境介质、滑动速度、载荷、滑动方向等因素对聚合物摩擦学性能的影响,对面向低温环境的聚合物摩擦学改性进行了简要总结,以期促进聚合物低温环境下摩擦学应用及其相关研究的进一步发展。

Polymers and composite materials have the advantages of good mechanical properties,low friction coefficient,and strong wear resistance.They are often used in the manufacture of key basic components of friction pairs,such as sealing rings,gears,bearing cages,rotor blades,pistons,etc.So far there has been very little research on polymer tribology for low temperature conditions,and the main work has focused on normal temperature and high temperature conditions.The theory of tribology applications and related preparation and modification processes of polymers and composites for low temperature environments is not complete.The tribological damage failure mechanism of polymers in extreme service environments is not yet fully understood.In addition,although polymer materials have many excellent properties,their shortcomings such as low surface hardness,large temperature effect,and easy deformation are also obvious.These shortcomings limit their application in the field of low temperature tribology.In order to solve this problem,the researchers carried out modification research on the polymer through filling fillers,surface treatment and other methods and have achieved certain results.At present,due to the continuous development of cutting-edge technologies such as aerospace,the tribological properties of polymers in va-cuum and low temperature environments have attracted widespread attention.Polymer self-lubricating materials such as polytetrafluoroethylene,polyimide,and polyether ether ketone have been used in spacecraft to make lubricating and sealing components.The researchersmodified the polymer with graphite,grapheme,molybdenum disulfide,aramid fiber,glass fiber,etc.And prepared PTFE/graphite,PTFE/Aramid fiber,PTFE/UHMWPE with low friction coefficient and high wear resistance under low temperature environment and other composite materials which have promoted the application of polymers in the field of low temperature tribology.This review systematically analyzes the influence of temperature,environmental medium,sliding speed,load,sliding direction and other factors on polymer tribological properties under low temperature environment,and briefly summarizes the polymer tribological modification for low temperature environment.In order to promote the further development of tribology applications and related research in low temperature environment of polymers.