碳基复合材料的制备及其摩擦学性能研究

发布时间：2018-03-05 05:32

本文选题：碳材料　切入点：聚酰亚胺　出处：《江苏大学》2017年硕士论文　论文类型：学位论文

【摘要】：在经济飞速发展和科技不断进步的今天,机械、航天和核工业已经占据了工业的主导地位,而在这些领域中摩擦的不可避免性,导致了润滑油的过度使用,这一现象加剧了能源危机和环境污染问题。为了资源和环境的可持续发展,发展绿色环保可持续发展的润滑体系变得尤为重要。首先是润滑剂的选择,水基润滑的来源比较广,而且成本比较低,已经在各种金属加工领域有着广泛的应用,用水基润滑代替油润滑也已经受到很多领域的青睐。因此探索一种高效可靠绿色环保的水基润滑添加剂对进一步推进水基润滑的应用具有重要意义。其次是固体润滑方向,如果材料本身具有润滑作用,那就会大大减轻资源的损耗和浪费。在固体润滑领域,碳材料、聚合物等都有着广泛的应用。本研究以研究绿色可持续发展的润滑体系为宗旨,研究了碳材料作为水基润滑添加剂的摩擦学行为以及碳材料作为聚合物自润滑复合材料添加剂的摩擦学行为。其主要研究内容如下:(1)通过改进的Hummers法制备了氧化石墨烯,并对多壁碳纳米管进行酸化处理。将制得的GO和MWCNTs-COOH通过溶液共混与真空过滤进行复合,制备GO/MWCNTs-COOH复合材料。研究了不同比例的GO/MWCNTs-COOH复合材料作为水基润滑添加剂的摩擦磨损行为。发现了GO:MWCNTs-COOH的最佳的比例为3:1,此时氧化石墨烯和碳纳米管之间通过π-π非共价键的结合形成了均一的网络插层结构,使得复合材料可以稳定的分散在水溶液中。GO/MWCNTs-COOH复合材料作为水基润滑添加剂的时候,在循环摩擦力的作用下有着协同作用,比相同含量的氧化石墨烯和碳纳米管单独加入水中时的润滑效果更优异。(2)通过原位聚合的方法将上述溶液共混真空过滤制备的GO/CNTs复合材料作为填料加入到聚酰亚胺(PI)基体中,制备GO/CNTs/PI复合材料。研究表明GO/CNTs复合材料对于PI基体具有协同增强的效果,GO/CNTs/PI复合材料具有优异的力学性能和热学性能,并且自润滑效果也非常显著。在干摩擦条件下,加入了GO/CNTs复合材料的PI基体的摩擦系数和磨损量都比纯的PI基体要低很多。同样地,在有水润滑介质时,GO/CNTs/PI复合材料摩擦磨损的行为依旧比纯的聚酰亚胺的摩擦性能优异。(3)通过冷压烧结的方法制备聚酰亚胺/聚偏氟乙烯复合材料和碳纤维/聚酰亚胺/聚偏氟乙烯复合材料,并研究了其力学、热学和摩擦学特性。研究表明:聚偏氟乙烯本身属于软质相,在加入了聚酰亚胺和碳纤维后,无论是力学还是摩擦学性能都得到了增强。聚偏氟乙烯的摩擦系数很低,但是磨损量却很高,加入了聚酰亚胺和碳纤维后,材料的耐磨性能得到了明显的改善,在固体润滑领域有很大的研究空间。
[Abstract]:Today, with the rapid development of economy and progress of science and technology, the mechanical, aerospace and nuclear industries have occupied the leading position of the industry, and the inevitable friction in these fields has led to the excessive use of lubricating oil. This phenomenon exacerbates the energy crisis and environmental pollution. For the sustainable development of resources and environment, it is particularly important to develop the lubricating system of green environmental protection and sustainable development. First, the choice of lubricant, the source of water-based lubrication is relatively wide. And the cost is relatively low, and has been widely used in various fields of metal processing, Water based lubrication instead of oil lubrication has been favored in many fields. Therefore, it is of great significance to explore an efficient, reliable, green and environmentally friendly water based lubricating additive to further promote the application of water based lubrication, followed by the direction of solid lubrication. If the material itself has lubricating effect, it will greatly reduce the loss and waste of resources. It is widely used in the field of solid lubrication, carbon materials, polymers, etc. The purpose of this study is to study the lubricating system of green and sustainable development. The tribological behaviors of carbon materials as water based lubricating additives and carbon materials as additives of polymer self-lubricating composites were studied. The main research contents are as follows: (1) graphene oxide was prepared by improved Hummers method. The multiwalled carbon nanotubes were acidified. The prepared go and MWCNTs-COOH were compounded by solution blending and vacuum filtration. GO/MWCNTs-COOH composites were prepared. Friction and wear behaviors of GO/MWCNTs-COOH composites with different proportions as water based lubricating additives were studied. It was found that the optimum ratio of GO:MWCNTs-COOH was 3: 1, and the 蟺-蟺 noncovalent reaction between graphene oxide and carbon nanotubes was found. The combination of keys forms a uniform network intercalation structure, So that the composite can be steadily dispersed in aqueous solution. GOR / MWCNTs-COOH composite is used as water based lubricating additive, and it has synergistic effect under the action of cyclic friction. The lubricating effect of graphene oxide and carbon nanotubes was better than that of graphene oxide and carbon nanotubes in water alone. The GO/CNTs composites prepared by vacuum filtration were added to the polyimide matrix by in-situ polymerization. GO/CNTs/PI composites were prepared. The results show that GO/CNTs composites have synergistic strengthening effect on Pi matrix. GOP / CNTs / Pi composites have excellent mechanical and thermal properties, and the self-lubricating effect is very remarkable. The friction coefficient and wear rate of Pi matrix added with GO/CNTs are much lower than that of pure Pi matrix. The friction and wear behavior of GO- / CNTs- / Pi composites is still better than that of pure polyimides in aqueous lubricating media.) Polyimide / PVDF composites and carbon fiber / polyimides were prepared by cold pressing sintering. Amine / polyvinylidene fluoride composites, The mechanical, thermal and tribological properties of polyvinylidene fluoride (PVDF) were studied. Both mechanical and tribological properties have been enhanced. The friction coefficient of PVDF is very low, but the wear rate is very high. With the addition of polyimide and carbon fiber, the wear resistance of the material is obviously improved. There is much room for research in the field of solid lubrication.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB332

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