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1.
Five kinds of PEEK/CF composites, made by blending poly-ether-ether-ketone (PEEK) with three kinds of PAN type carbon fibers (CFs) and two kinds of pitch type CFs respectively, were injection-molded into gears. Their gear performance such as the load capability and the wear of tooth were evaluated. The wear properties of PEEK/CF gears extremely varied depending on the kinds of CFs, when the same type gears were combined and grease was initially applied. Also, the load capabilities were significantly influenced by the affinity between PEEK and CF. A composite gear reinforced with CF of the highest density indicated the highest load capability irrespective of the test conditions, due to the lowest abrasive property of the CF as well as the excellent affinity between PEEK and CF. Its load capability under a high temperature running condition was found to be superior to that of polyamideimide (PAI) composite gear or polyphenylenesulphide (PPS) composite gear.  相似文献   
2.
Various polymeric blends based on sulfonated poly(ether ether ketone) (sPEEK)/poly(vinylidene fluoride) (PVdF) were prepared for the membranes of direct methanol fuel cell. The blend membranes showed good compatibility within a limited composition range of less than around 10 wt% of PVdF. The blend membrane containing 2.5 wt% exhibited highest proton conductivity at room temperature among the tested blends. The dimensional stability was enhanced with introducing PVdF into the blend membrane. These could contribute to high performance of the cell based on the blend membrane.  相似文献   
3.
Driven by economical and ecological reasons, thermoplastic-based coatings become a potential solution for anti-wear purpose. Two coating design concepts, flame spraying and printing PEEK (poly-ether-ether-ketone)-based coatings on Al substrate, were introduced in this paper. An amorphous PEEK coating was obtained by these two techniques. After being annealed, the coating presents a semi-crystalline structure. The friction and wear behaviors of PEEK-based coatings were investigated by means of ball-on-disc tests. The results show that PEEK coatings exhibit an excellent tribological performance with a relatively low coefficient of friction and wear rate. The semi-crystalline PEEK coating exhibits a lower friction coefficient and wear rate than the amorphous one. The additions of micron-sized particles such as SiC and graphite in PEEK coating can improve significantly the coating wear resistance.  相似文献   
4.
In this work, the effects of sliding velocity and applied load on the tribological characteristics, i.e. friction coefficient and wear rate, of an amorphous poly-ether–ether–ketone (PEEK) coating was examined. Friction tests were performed on a ball-on-disc apparatus. Based on analyses of the worn tracks, a comprehensive attempt is made to approach the tribological mechanism of amorphous PEEK. A hypothesis is proposed that the tribological behaviour of the amorphous PEEK is closely related to its viscoelastic behaviour. The sliding velocity plays significant roles on the tribological characteristics by influencing the interface temperature and strain rate of the PEEK surface layer involved in the friction process. The applied load influences the tribological performance by varying the strain range in the surface layer.  相似文献   
5.
采用模压法制备了PEEK多元复合材料,用环-块磨损实验机对复合材料进行了磨损试验,用SEM方法对复合材料的磨损表面进行了观察和分析,并利用DSC、红外光谱(FTIR)和SEM分析方法对复合材料的磨屑进行了研究,并探讨了复合材料的磨损机制。结果表明:与PEEK相比,复合材料具有优良的摩擦学性能;PEEK复合材料磨屑的熔点比相应模压材料有所降低,且磨屑的熔限比相应的模压材料有所加宽;随着Ekonol含量的增加,复合材料的磨损机制发生了由粘着磨损为主向疲劳磨损为主的转变;通过磨屑形貌分析和对磨损表面的观察与分析所得的关于复合材料的磨损机制的结论是一致的。  相似文献   
6.
采用均匀设计法设计了CF/SiO2/PTFE/PEEK复合材料,并模压成型;在摩擦磨损试验机上研究了PEEK复合材料的摩擦学特性,应用回归分析法对其摩擦学特性试验数据进行了分析,得到了摩擦学特性参数的回归公式。结果表明,均匀设计法应用于PEEK复合材料的摩擦学特性研究是可行的,能有效预测复合材料的摩擦学特性参数,回归分析结果与复合材料的摩擦磨损试验数据相吻合。  相似文献   
7.
PEEK基自润滑复合材料的摩擦学研究和应用   总被引:1,自引:1,他引:1  
聚醚醚酮(PEEK)基自润滑复合材料具有摩擦因数低、耐磨性好等特点,可以在无润滑、高温、潮湿、污染、腐蚀等恶劣环境下使用。本文综述了对聚醚醚酮(PEEK)基复合材料摩擦学研究的新进展,讨论了纤维增强、无机填充、有机共混改性以及温度、对偶和介质、固体润滑剂等对PEEK基复合材料摩擦学性能的影响,介绍了PEEK基复合材料在人工关节假体材料方面的应用,指出PEEK摩擦复合材料今后的研究方向,以期扩大PEEK复合材料的摩擦学工程应用。  相似文献   
8.
研究了不锈钢纤维/碳纤维混杂增强聚醚醚酮(PEEK)树脂基半金属摩擦材料的配比、成型工艺对其摩擦磨损性能的影响,对其摩擦磨损机理进行了初步分析.结果表明:制备摩擦材料的优化工艺条件是热压温度320 ℃、压力35 MPa、保温时间3 min/mm,固化处理工艺为80 ℃×30 min 150 ℃×30 min 270 ℃×30 min 320 ℃×180 min;最佳配方为19.63%的PEEK、7.57%的不锈钢纤维、10.97%的碳纤维、6.51%的腰果壳油粉及55.33%的填料.经优化工艺制备的摩擦材料的摩擦因数稳定,磨损率低,摩擦材料的磨损在低温区主要属于磨粒磨损,在较高温度时属于粘着磨损和磨粒磨损的共同作用.  相似文献   
9.
A series of blends with Polytetrafluroethylene (PTFE) powder and Polyetheretherketone (PEEK) was developed by varying the PTFE contents in steps of 5 wt.% from 0 to 20 wt.%. The composites were evaluated for their friction and wear properties at room temperature as well as high temperature in low amplitude oscillating wear (LAOW) mode against steel (100 Cr 6) ball against polymer plate. The same blends were also evaluated in abrasive wear mode to study the influence of harsh operating conditions on wear and friction performance. Incorporation of PTFE benefited PEEK in various ways such as it increased the tribo-utility of the latter by increasing its limiting load value, removing its stick-slip tendency, lowering coefficient of friction and specific wear rate significantly. With increase in PTFE content, benefits to the wear performance increased regularly. This was not the case for friction coefficient. Lowest μ was recorded for 15% PTFE contents. The enhancement in wear and friction performance, however, was at the cost of strength properties which decreased substantially with increase in PTFE content. At 100 °C, friction coefficient and wear rates of all blends increased marginally. In abrasive wear mode, on the other hand, PTFE filled PEEK showed poorer wear resistance than neat PEEK. This was correlated with strength properties and it was observed that these blends closely followed the predictions of Ratner–Lancaster plot. SEM was used to examine the micro-structural features of worn surfaces.  相似文献   
10.
The tribological properties of two kinds of high temperature resistant thermoplastic composites, polyetheretherketone (PEEK) and polyetherimide (PEI), reinforced with short carbon fibre (SCF), graphite flakes, and sub-micro particles of TiO2 and ZnS, were investigated in dry sliding conditions. Friction and wear experiments were conducted on a pin-on-disc apparatus, using composite pins against polished steel counterparts, performed within moderate pv-ranges at room and elevated temperatures (up to 150 °C). It was found that conventional fillers, i.e. SCF and graphite flakes, could effectively enhance both the wear resistance and the load-carrying capacity of the base polymers. With the addition of sub-micro particles, the frictional coefficient and wear rate of the composites were further reduced especially at elevated temperatures. On the basis of microscopic observation of worn surfaces, dominant wear mechanisms are discussed.  相似文献   
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