混杂填料增强聚四氟乙烯复合材料的摩擦学性能研究

采用MM-200型摩擦磨损试验机对纳米SiC、MoS2和石墨填充聚四氟乙烯(PTFE)复合材料在干摩擦条件下与45#钢对摩时的摩擦磨损性能进行了研究,探讨了MoS2、石墨及纳米SiC的协同效应。认为纳米SiC的加入大大提高了复合材料的承载能力,石墨、MoS2的加入减少PTFE复合材料的摩擦因数。利用扫描电子显微镜(SEM)对PTFE复合材料的摩擦面进行了观察。结果表明:实验中5%nano-SiC和3%MoS2填充PTFE复合材料的摩擦磨损性能最好,且在高载荷下的摩擦磨损性能尤为突出,具有一定的应用价值。     

石墨填充对均苯型聚酰亚胺材料性能的影响

以均苯四甲酸酐(PMDA)和4,4'-二氨基二苯醚(ODA)为原料,通过热亚胺化的方式,合成不同石墨填充量的均苯型聚酰亚胺模塑粉,并对其化学结构、比浓对数黏度和石墨含量进行测试表征。将聚酰亚胺模塑粉热模压成型,制备聚酰亚胺复合材料,测试石墨填充对其力学性能和摩擦性能的影响。结果表明,石墨的加入对聚酰亚胺树脂的化学结构没有明显影响。随着石墨质量分数的增大,聚酰亚胺材料的力学性能有所下降,但高温性能保持能力有所提升。石墨的加入显著改善了聚酰亚胺材料的摩擦磨损性能,摩擦系数和磨痕宽度明显降低。     

混杂纤维/POE-g-MAH复合增强PA66耐磨材料

采用双螺杆挤出机制备聚酰胺66(PA66)/碳纤维/玻璃纤维材料和PA66/碳纤维材料,另外加入相容剂马来酸酐接枝聚烯烃弹性体(POE–g–MAH)来改善相界面的相容性,同时评价其力学性能和摩擦磨损性能。结果表明:在碳纤维增强PA66材料的研究过程中引入玻璃纤维可降低最高界面温度并且使摩擦系数降低,有助于改善PA66材料的摩擦学性能,共混物的摩擦过程以磨粒磨损和粘着磨损为主。此外,在添加入玻璃纤维后,15%混杂纤维填充比15%碳纤维单独填充的PA66材料拉伸强度提高9.89%,冲击强度提高34.02%;而添加入20%混杂纤维与20%碳纤维单独填充的PA66材料相比,拉伸强度提高了71.65%,冲击强度提高了26.23%。     

纳米SiC及其与石墨、二硫化钼填充PTFE基复合材料摩擦磨损性能研究

用摩擦磨损试验机对纳米碳化硅（SiC）及其与石墨、二硫化钼（MoS2）混合填充聚四氟乙烯（PTFE）复合材料在干摩擦条件下与45#钢对磨时摩擦磨损性能进行了研究,用洛氏硬度计对PTFE及其复合材料的硬度进行了测量,用扫描电子显微镜对PTFE复合材料磨损表面进行了观察。结果表明,纳米SiC的加入能提高PTFE复合材料的硬度和耐磨性,纳米SiC与MoS2混合填充会使PTFE复合材料的耐磨性提高更多,特别是在载荷增大时其耐磨效果更好。纳米SiC填充PTFE复合材料的摩擦因数比纯PTFE大,且随载荷增加有所减小, MoS2、石墨的加入可降低PTFE的摩擦因数。     

改性二硫化钼填充型复合材料的磨损性能及机理研究

以硅烷偶联剂(KH570)、十六烷基三甲基溴化铵(CTAB)、硬脂酸(SA)、马来酸酐(MA)及其复合改性荆对二硫化钼(MoS2)粉体进行表面改性,得到了良好亲油性的粉体;通过模压成型制得改性MoS2填充型聚苯硫醚(PPS)/聚丙烯(PP)复合材料.磨损试验表明,填充型复合材料的磨损率均低于未填充的材料,SA/MoS2填充型PPS/PP的磨损率最小,为0.7216%,KH570/MoS2填充型PPS/PP的磨损率是填充型试样中最高的,为5.4187%;扫描电镜(SEM)分析表明,受损程度与磨损率数据基本一致,并据此得出磨损机理:摩擦过程中,主要进行磨粒磨损和黏附转移磨损,开始时磨粒磨损占主导地位,磨损率较高,随后黏附转移磨损逐渐占据主导地位,磨损率较小,磨损过程中两者同时存在,并且相互转变.     

PA6／纳米A12O3复合材料摩擦性能的研究

研究了纳米Al2O3填充PA6复合材料的摩擦性能。通过分析纳米Al2O3含量、载荷对材料摩擦系数和耐磨性能的影响，得到复合材料中纳米Al2O3为6wt％时，材料的摩擦性能最好。通过SEM图片分析试件摩擦表面形貌，发现复合材料的磨损机理从纯PA6材料的粘着磨损转为轻微的磨粒磨损和粘着磨损。     

固体润滑剂对玻纤PA66复合材料摩擦磨损性能的影响

采用双螺杆挤出造粒制备了不同固体润滑剂改性尼龙66(PA66)的复合材料,复合材料含30%玻纤(GF),对复合材料的力学性能和摩擦磨损性能进行表征,研究了不同润滑剂对材料性能的影响。结果表明,玻纤的添加可以明显提高材料的力学性能,固体润滑剂的加入,材料的力学性能稍微降低,但是变化不大。固体润滑剂聚四氟乙烯(PTFE)、石墨、二硫化钼(MoS_2)中,PTFE的减摩耐磨效果最佳,且PTFE的含量越高,复合材料的摩擦磨损性能越好,且不同润滑剂复配材料的摩擦磨损性能低于相同含量的PTFE。一定范围内,载荷越高,材料的摩擦因数越小;速度越快,材料的摩擦因数越高,但是磨损量随着速度和载荷的增加而显著提高。     

碳纳米管/石墨/碳纤维增强聚酰亚胺树脂复合材料的摩擦磨损性能研究

在本文中,通过浸涂和热成型工艺做准备,将石墨(GR)或碳纳米管(CNTs),或把两者一起结合在纳入碳纤维增强聚酰亚胺(CFRP)复合材料,利用块上环排列方法研究复合材料的摩擦磨损性能。实验结果表明,当它们单独使用时,理想型石墨比碳纳米管更有利于提高碳纤维增强塑料复合材料的摩擦学性能。值得注意的是,加入石墨时,碳纳米管填充碳纤维增强塑料复合材料的摩擦磨损性能进一步提高了,表明它们之间存在协同效应。     

纤维填充PTFE复合材料的摩擦学研究

在聚四氟乙烯（PTFE）中分别填充碳纤维（CF）、玻璃纤维（GF）及这两种纤维不同配比的混杂纤维（HF），制备了具有不同力学性能和摩擦磨损性能的PTFE基复合材料。探讨了填料组成对复合材料硬度和干摩擦条件下摩擦磨损性能的影响，并研究了PTFE基复合材料磨损表面的形貌学。结果表明，适量填充CF和GF均可提高PTFE的摩擦磨损性能，CF比GF效果更为显著；CF和GF的混杂纤维填充PTFE复合材料．表现出一定的协同性，比填充单种纤维，其效果更显著。     

PA6/纳米Al_2O_3复合材料摩擦性能的研究

研究了纳米Al2 O3 填充PA6复合材料的摩擦性能。通过分析纳米Al2 O3 含量、载荷对材料摩擦系数和耐磨性能的影响,得到复合材料中纳米Al2 O3 为 6wt%时,材料的摩擦性能最好。通过SEM图片分析试件摩擦表面形貌,发现复合材料的磨损机理从纯PA6材料的粘着磨损转为轻微的磨粒磨损和粘着磨损     

二硫化钼对SBRL力学性能和耐磨性能的影响

通过添加不同用量和种类的二硫化钼（MoS2）制备丁苯胶乳（SBRL）／MoS2复合材料,考察了复合材料的物理机械性能和耐磨性能。结果表明：随着MoS2用量增加,SBRL／MoS2复合材料的物理机械性能不断提高,摩擦因数不断降低,耐磨性能越好;MoS2经复配改性后,制备的SBRL／MoS2复合材料的物理机械性能和耐磨性能更好。     

Improved tribological properties of polyimide composites by micro–nano reinforcement

The hydroxylate carbon nanotubes (CNTs) were grafted by chemical method on the surface of the oxidized carbon fibers (CF) to improve the mechanical and tribological properties of polyimide (PI). The microstructure and fracture surface of the polyimide composites indicated that CF–CNTs hybrid as a multiscale reinforcement can distribute into the PI matrix homogeneously. Tribo-tests further showed that CF–CNTs hybrid had a better effect on hardness increment, impact strength enhancement, friction reduction, and wear resistance. Compared to the neat PI, the friction coefficient and wear rate of CF–CNTs/PI composite deceased by 23.2 and 55.9%, respectively. In particular, the loading capacity and high speed resistance of CF–CNTs/PI composite were greatly improved. The corresponding wear mechanisms were also discussed by observing the worn surface of the PI composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47900.     

铜及其氧化物填充UHMWPE力学、摩擦学性能研究

在超高分子量聚乙烯(UHMWPE)中分别填充铜粉、氧化铜粉和氧化亚铜粉,用万能材料试验机、摩擦磨损试验机等研究了三种填料对UHMWPE复合材料力学性能和摩擦磨损性能的影响,利用扫描电子显微镜对几种材料的磨损表面进行了观察和分析。结果表明,在填料添加量相同时,铜粉的减摩耐磨效果最好,氧化铜粉的减摩耐磨效果次之,氧化亚铜粉的减摩耐磨效果最差;以体积分数25％的铜粉填充的UHMWPE复合材料,具有良好的力学性能和摩擦学性能,是一种有应用前景的聚合物基减摩抗磨材料。     

Tribological behavior of polyetheretherketone composites containing short carbon fibers and potassium titanate whiskers in dry sliding against steel

Polyetheretherketone (PEEK) composites reinforced by short carbon fibers (SCF) and potassium titanate whiskers (PTW) were prepared using twin‐screw extrusion compounding and injection molding. The tribological properties of hybrid composites were investigated in dry sliding condition against steel. The effects of filler contents on the wear behavior were studied. It was found that the hybrid composite showed an excellent tribological property in dry sliding condition. Applied load had great effect on the tribological behavior of the composites. In most cases, the friction coefficient of the composite decreased with the load rising. The composites with higher CF contents showed outstanding tribological performances at low load but could worsen the wear behavior at high load. Because of the positive effect of PTW, high PTW loading composites presented low wear rate at low load. At high loads, the composites with lower PTW contents had better wear resistance. The scanning electron microscopy (SEM) observation revealed that abrasion wear was attributed to the lower wear resistance of the high PTW content composite at high load. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Influence of PTFE as a solid lubricant on the mechanical,electrical, and tribological properties of CF-reinforced PC composites

The objective of this research was to study the effects of polytetrafluoroethylene (PTFE) as a solid lubricant on the mechanical, electrical, and tribological properties of carbon fiber (CF)-reinforced polycarbonate (PC) composites. Samples were prepared by means of single-screw extrusion and injection molding processes. The mechanical tests included tensile, flexural, and failing weight impact tests, while the electrical tests consisted of surface and volume resistivity tests. The tribological testing was conducted under dry sliding conditions using pin-on-disk configuration. The results showed that the addition of CF managed to significantly reduce the electrical resistivity as the CF loading approached 10–15 wt%. The addition of PTFE managed to reduce the resistivity of the composite, that is, from 4.51 to 0.53 × 10 (Ωcm). The incorporation of 15 wt%. CF resulted with an increase of 45% in tensile strength and 51.5% in flexural strength, while the addition of PTFE had a negative impact on both properties. It was shown that PTFE was able to reduce the friction coefficient, μ and wear rate, K up to 0.257 and 6.35 × 10⁶ (mm³/Nm), respectively, which can be attributed to the excellent abilities of PTFE to form transfer film. The composite consisting of 15 wt% CF and 10 wt%. PTFE showed highest improvement in term of electrical resistivity, and is deemed the most suitable composition for this study. Scanning electron microscopy was also carried out to further elucidate the fracture and wear mechanism of the PC/CF/PTFE composites.     

Tuning the properties of carbon fiber-reinforced poly(phenylene sulphide) laminates via incorporation of inorganic nanoparticles

Novel carbon fiber (CF)-reinforced poly(phenylene sulphide) (PPS) laminates incorporating inorganic fullerene-like tungsten disulfide (IF-WS₂) nanoparticles were prepared via melt-blending and hot-press processing. The influence of the IF-WS₂ on the morphology, thermal, mechanical and tribological properties of PPS/CF composites was investigated. Efficient nanoparticle dispersion within the matrix was attained without using surfactants. A progressive rise in thermal stability was found with increasing IF-WS₂ loading, as revealed by thermogravimetric analysis. The addition of low nanoparticle contents retarded the crystallization of the matrix, whereas concentrations equal or higher than 1.0 wt% increased both the crystallization temperature and degree of crystallinity compared to those of PPS/CF. Mechanical tests indicated that with only 1.0 wt% IF-WS₂ the flexural modulus and strength of PPS/CF improved by 17 and 14%, respectively, without loss in toughness, ascribed to a synergistic effect between the two fillers. A significant enhancement in the storage modulus and glass transition temperature was also observed. Moreover, the wear rate and coefficient of friction strongly decreased, attributed to the lubricant role of the IF-WS₂ combined with their reinforcing effect. These inorganic nanoparticles show great potential to improve the mechanical and tribological properties of conventional thermoplastic/CF composites for structural applications.     

Friction and wear mechanisms of PA66/PPS blend reinforced with carbon fiber

The mechanical and tribological properties of carbon fiber (CF) reinforced polyamide 66 (PA66)/polyphenylene sulfide (PPS) blend composite were studied in this article. It was found that CF reinforcement greatly increases the mechanical properties of PA66/PPS blend. The friction coefficient of the sample decreases with the increase of CF content. When CF content is lower (below 30%), the wear resistance is deteriorated by the addition of CF. However, the loading of higher than 30% CF significantly improves the tribological properties of the blend. The lowest friction coefficient (0.31) and the wear volume (1.05 mm³) were obtained with the PA66/PPS blend containing 30% CF. The transfer film and the worn surface formed by sample during sliding were examined by scanning electron microscopy. The observations revealed that the friction coefficient of PA66/PPS/CF composite depends on the formation and development of a transfer film on the counterface. The abrasive wear caused by ruptured CFs (for lower CF content) and the load bearing ability of CFs (for higher CF content) are the major factors affecting the wear volume. In addition, the improvements of mechanical properties, thermal conductivity, and self‐lubrication of bulk CFs are also contributed to the wear behavior of PA66/PPS/CF composite. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

The effect of annealing of milled carbon fibers on the mechanical and tribological properties of solid-lubricant thermoplastic polyimide-based composites

The mechanical and tribological properties of polyimide (PI)-based composites loaded with polytetrafluoroethylene (PTFE) and milled carbon fibers (MCF) in the as received and annealed states were studied in order to increase adhesion to the polymer matrix. It has been shown that loading with micron-range MCF (200 μm) doubles elastic modulus of the composites while all other physical and mechanical properties remain at neat PI levels. The three-component composite loaded with annealed MCF and PTFE has possessed the highest wear resistance. In comparison with neat PI, its wear rate has decreased by ∼312 times for the metal-polymer tribological contact and by ∼286 times for the ceramic-polymer one. Based on the obtained experimental data, the most preferential conditions for their implementation (load-speed modes for the given types of the tribological contacts) have been determined using a developed computer algorithm. The designed solid-lubricant ''PI + 10 wt% PTFE + 10 wt% MCF_annealed'' composite has been recommended for both metal-polymer and ceramic-polymer tribological units.