多孔自润滑复合材料摩擦学性能及有限元模拟研究

发布时间：2018-03-18 01:18

  本文选题：多孔聚合物　切入点：自润滑　出处：《东北石油大学》2015年硕士论文　论文类型：学位论文

【摘要】：多孔聚合物基自润滑复合材料自身具备多孔结构或多孔载体,润滑油或润滑脂可以贮存在这些孔道或载体中。摩擦时,由于摩擦热和载荷的耦合作用,润滑油脂持续且稳定地析出,在摩擦表面形成稳定的润滑油膜,起到减摩耐磨作用,具有广阔的应用前景。本文制备了多孔聚合物基自润滑复合材料,研究了造孔剂含量或润滑添加剂对复合材料摩擦学性能的影响,结合扫描电子显微镜(SEM)对复合材料内部结构、磨损面及对偶面等进行多角度观察和分析,讨论了相关摩擦磨损机理。同时,借助有限元分析,进一步揭示多孔自润滑复合材料的孔隙结构及孔隙率与摩擦磨损性能之间的内在规律以及摩损面上自润滑膜的成膜机理。论文的主要研究内容和结论可归纳如下:1.选用聚醚醚酮(PEEK)为基体材料,NaCl为造孔剂,锂基润滑脂为润滑剂,采用模压滤取、真空熔渍方法制备了多孔聚醚醚酮(PEEK)基自润滑复合材料。首先,通过摩擦实验,考察了造孔剂含量对多孔PEEK复合材料内部结构与摩擦磨损性能的影响。其次,根据PEEK复合材料在持续旋转双环摩擦运动中摩擦热及应力变化特点,结合材料SEM分析,建立二维几何轴对称模型。最后,通过数值分析,考察了材料在温度场与应力场的性能特征,分析了孔隙率对多孔PEEK基复合材料的温度、位移及应力分布情况的影响。结果表明,模拟结果与实测值的最大误差小于7%。该研究有助于指导多孔PEEK基自润滑复合材料的制备及摩擦学性能的研究。2.以聚苯硫醚(PPS)为基体材料制备了多孔聚苯硫醚(PPS)基自润滑复合材料。实验结果表明,NaCl含量为30wt.%,孔隙率为21%时,多孔PPS复合材料的摩擦系数、磨损率及接触表面温度为最小值,分别为0.026、3.75×10-16m3(Nm)-1及44.3℃。与纯PPS相比,其摩擦系数减小90%,耐磨性能增强1.3×104倍。根据多孔材料微观形貌,建立二维等效体积单元模型,设计结构参数λ进行孔隙率计算。仿真复合材料摩擦运动,采用热-应力耦合场分析方法,考察了摩擦过程中材料的温度及应力分布云图。同时,分析了材料的孔结构及孔隙率对润滑脂的析出速率的影响,揭示了多孔PPS自润滑材料的自润滑机理。3.采用真空浸渍-滤洗方法制备了含油活性炭粉末(ACs-oil),然后将ACs-oil均匀地添加到环氧树脂中,制备了环氧树脂基自润滑复合材料(ACs-oil/EP)。考察了不同ACs-oil含量对ACs-oil/EP自润滑复合材料的摩擦学性能的影响。实验结果表明,摩擦条件为1MPa、0.52m/s,ACs-oil含量为10wt.%,复合材料摩擦系数与磨损率分别为0.47与11.5×10-14m3(Nm)-1。与纯环氧相比,摩擦系数降低26%,耐磨损性提高3.21倍。结合SEM和EDS分析断面、磨损面与对偶面微观形貌,讨论了ACs-oil/EP自润滑材料的自润滑机理。
[Abstract]:Porous polymer based self-lubricating composites have porous structures or porous carriers, and lubricating oil or grease can be stored in these channels or carriers. The lubricating oil precipitates continuously and stably, and forms a stable lubricating oil film on the friction surface, which has the function of reducing friction and wear resistance, and has broad application prospects. In this paper, porous polymer based self-lubricating composites were prepared. The effect of the content of pore-making agent or lubricating additive on the tribological properties of the composite was studied. The internal structure, wear surface and dual surface of the composite were observed and analyzed from different angles combined with the scanning electron microscope (SEM). The related friction and wear mechanism is discussed. At the same time, with the help of finite element analysis, The internal rules between pore structure, porosity and friction and wear properties of porous self-lubricating composites and the film forming mechanism of self-lubricating film on friction surface are further revealed. The main contents and conclusions of this paper can be summarized as follows. Using polyether ether ketone (PEEK) as matrix material and NaCl as pore-forming agent, The porous polyether ether ketone peek (PEEK) based self-lubricating composite was prepared by the method of molding filtration and vacuum melting with lithium grease as lubricant. The effects of pore-forming agent content on the internal structure and friction and wear properties of porous PEEK composites were investigated. Secondly, according to the characteristics of friction heat and stress of PEEK composites during the continuous rotating double-ring friction movement, the SEM analysis was carried out. A two-dimensional geometric axisymmetric model was established. Finally, through numerical analysis, the properties of the material in the temperature field and stress field were investigated, and the temperature of porous PEEK matrix composites was analyzed. The effect of displacement and stress distribution. The results show that, The maximum error between the simulated results and the measured values is less than 7. This study is helpful to guide the preparation and tribological properties of porous PEEK matrix composites .2.The porous polyphenylene sulfide (PPS) based composites were prepared by using polyphenylene sulfide (PPS) as matrix material. Self-lubricating composites. The experimental results show that when the NaCl content is 30 wt. and the porosity is 21, The friction coefficient, wear rate and contact surface temperature of porous PPS composites are the minimum values of 0.026 ~ 3.75 脳 10 ~ (-16) m ~ (-3) Nm ~ (-1) and 44.3 鈩，

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