稀土对玻璃纤维填充金属-塑料多层复合材料抗冲击磨损性能的影响

研究了稀土元素处理玻璃纤维填充金属－塑料多层复合材料在冲击载荷、干摩擦条件下的摩擦和磨损性能，并利用扫描电子显微镜（SEM）对磨损表面进行了观察和分析，结果表明，用稀土表面改性剂处理玻璃纤维表面，可以提高玻璃纤维与聚四氟乙烯之间的界面结合力，改善复合材料的界面性能，并有利于在偶件表面形成分布均匀、结合强度高的转移膜，使复合材料与偶件表面之间的对摩减轻，大幅度地降低了复合材料的磨损，从而使复合材料具有优良的摩擦性能和抗冲击磨损性能。     

Tribological behavior of polyurethane-based composite coating reinforced with TiO2 nanotubes

The unmodified and hexamethylene diisocyanate (HDI) modified TiO₂ nanotubes, were used for fabricating TiO₂ nanotubes (TiNTs)/polyurethane (PU) composite coating. The effects of applied load and sliding speed on the tribological behavior of the composite coating were investigated using a block-on-ring wear tester. Compared to the TiO₂ nanotubes filled PU composite coating, the HDI modified TiO₂ nanotubes (TiNTs-HDI) filled one had the lower friction coefficient and higher wear life under various applied loads and sliding speed. Scanning electron microscope (SEM) investigation showed that the TiNTs-HDI filled PU coating had smooth worn surface under given applied load and sliding speed, and a continuous and uniform transfer film formed on the surface of the counterpart ring, which helped to reduce the wear of the coating. The improvement in the tribological properties of TiNTs-HDI/PU composite coating might due to an improvement in interfacial adhesion between TiNTs and PU after HDI treatment. The strong interfacial coupling of the composite coating made TiNTs-HDI not easy to detach from the PU matrix, and prevented the rubbing-off of PU composite coating, accordingly improved the friction and wear properties of the composite coating.     

The oxidation‐treated interface on tribological properties of carbon fibers‐reinforced PTFE composite under oil‐lubricated condition

The effect of air oxidation and ozone surface treatment of carbon fibers (CF) on tribological properties of CF reinforced polytetrafluoroethylene (PTFE) composites under oil‐lubricated condition was investigated. Experimental results revealed that ozone treated CF reinforced PTFE (CF–PTFE) composite had the lowest friction coefficient and wear under various applied loads and sliding speeds compared with untreated and air‐oxidated composites. X‐ray photoelectron spectroscopy (XPS) study of carbon fiber surface showed that, after ozone treatment, oxygen concentration was obviously increased, and the amount of oxygen‐containing groups on CF surfaces was largely increased. The increase in the amount of oxygen‐containing groups enhanced interfacial adhesion between CF and PTFE matrix. With strong interfacial adhesion of the composite, stress could be effectively transmitted to carbon fibers; carbon fibers were strongly bonded with PTFE matrix and large scale rubbing‐off of PTFE was prevented, therefore, the tribological properties of the composite were improved. Copyright © 2009 John Wiley & Sons, Ltd.     

Study on the friction and wear behavior of surface‐modified carbon nanotube filled carbon fabric composites

The functionalization of multi‐walled carbon nanotubes (MWNTs) was achieved by grafting furfuryl amine (FA) onto the surfaces of MWNTs. Furthermore, the functional MWNTs were incorporated into carbon fabric composites and the tribological properties of the resulting composites were investigated systematically on a model ring‐on‐block test rig. Friction and wear tests revealed that the modified MWNTs filled carbon fabric composite has the highest wear resistance under all different sliding conditions. Fourier transform infrared spectroscopy (FTIR), X‐ray photoelectron spectroscopy (XPS), and thermal gravimetric analysis (TGA) revealed that MWNTs were successfully functionalized and the modification led to an improvement in the dispersion of MWNTs, which played an important role on the enhanced tribological properties of carbon fabric composites. It can also be found that the friction and wear behavior of MWNTs filled carbon fabric composites are closely related with the sliding conditions such as sliding speed, load, and lubrication conditions. Copyright © 2010 John Wiley & Sons, Ltd.     

Plasma treatment of carbon fiber on the tribological property of polyimide composite

The effect of different ratios of carbon fiber (CF) reinforcing polyimide (PI) and surface treatment of CF on the microstructure and wear resistance of surface layers was studied. The increase of CF content led to a gradual increase in the Interlaminar shear strength (ILSS) values, and the maximum ILSS value arises when the CF content is 15 vol%, with an improvement of 13.45% compared to virgin CF composites. The increased interfacial adhesion could be contributed mainly to the presence of branched PI at the interface region. SEM of the worn surface confirms that the plasma treatment efficiently improves the interfacial adhesion of CF/PI composite. Copyright © 2017 John Wiley & Sons, Ltd.     

Enhancement on interlaminar shear strength and water‐lubricated tribological performance of high‐strength glass fabric/phenolic laminate by the incorporation of carbon nanotubes

High‐strength glass fabric (HSGF)/phenolic laminates modified with different contents of carbon nanotubes (CNTs) were fabricated by hot‐compression technique. The effects of CNTs on the interface of HSGF/phenolic, interlaminar shear strength (ILSS) and water‐lubricated tribological performance of HSGF/phenolic laminate were investigated. The ILSS of the laminates were tested on a universal testing machine (DY35), and the tribological properties were evaluated by a block‐on‐ring tribo‐tester. The interfaces of HSGF/phenolic and the worn surfaces of the laminates were analyzed by scanning electron microscope. The results showed that the moderate incorporation of CNTs improved the interface of HSGF/phenolic and accordingly enhanced the ILSS of the laminate. Besides, the friction coefficient of HSGF/phenolic laminate sliding against stainless steel in water can be remarkably stabilized and lowered by the incorporation of CNTs due to the better water lubrication induced by added CNTs and the intrinsic self‐lubrication of CNTs which were further graphitized during the friction and wear process. And the wear rate of the laminate can be accordingly reduced by 1 order of magnitude. The results indicate that CNTs have excellent potential in enhancing both ILSS and tribological fabric/polymer laminate composite, which will greatly improve the current situation of deterioration on mechanical properties by adding traditional solid lubricants. Copyright © 2014 John Wiley & Sons, Ltd.     

Investigation of transfer film of PTFE/bronze composites on 2024Al surface

Polytetrafluoroethylene (PTFE) composites filled with 10–30% volume content of bronze powder were prepared through molding and sintering process. Transfer films of these composites were prepared on surface of 2024 Al bar through friction method under certain condition. Roughness, morphology, andelement of these transfer films were investigated using scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) methods. Tribological propertiesof these transfer films sliding against GCr15 steel ball were tested using a DFPM reciprocating tribometer. Worn surfaces were observed and analyzed using SEM and EDS methods. It was found that uniformity and continuity of the transfer films were obviously improved by the increase of bronze content of the composites. Transfer films with better uniformity and continuity holds longer wear life. Considerably lower friction coefficient and longer wear life of these transfer films indicate that the transfer films prepared in the experiment could effectively prevent direct contact of metal friction pair and thus protect them from heavy wear. SEM and EDS analyses of the worn surfaces indicate that adhesion wear and fatigue wear were main wear modes of the transfer film. Copyright © 2009 John Wiley & Sons, Ltd.     

The flexural and tribological properties of UHMWPE composite filled with plasma surface‐treated wood fibers

In this paper, the wear performance of an ultra‐high molecular weight polyethylene composites filled with wood fiber were studied using a pin‐on‐disc method. The effects of surface treatment of wood fiber and sliding load and on the friction and wear of the wood fiber/UHMWPE composite are reported. The test results showed that the sliding load is an important controlling factor; its effect is diminished when the wood fiber is modified.     

Investigation of sub‐micron size cenosphere fillers and filler loading on the mechanical and tribological peculiarity of polyester composites

This paper investigates the effect of sub‐micron size cenosphere filler and filler loading on mechanical and dry sliding wear property of polyester composites. Composites are fabricated by filling with 10 and 20 wt% of 800 and 200‐nm size of cenosphere filler particles. Neat polyester composite is also prepared for comparison analysis. Dry sliding wear test is conducted for these composites over a range of sliding distance with different sliding velocities and applied loads on a pin‐on‐disc wear test machine. Taguchi methodology and analysis of variance (ANOVA) is used to analyze the friction and wear characteristics of the composites. The artificial neural network (ANN) approach is implemented to the friction and wear data for corroboration. In this work, mechanical properties of composites such as hardness, tensile strength, tensile modulus, flexural strength, and compressive strength revealed that mechanical properties and wear resistance of the composites increase with a decrease in the particle size. The measured Young's moduli are comparable to standard theoretical prediction models. The morphology of worn composite specimens has been examined by scanning electron microscopy to understand the dominant wear mechanisms. Finally, optimal factor settings are determined using a genetic algorithm (GA). Copyright © 2017 John Wiley & Sons, Ltd.     

The effect of surface modification with nitric acid on the mechanical and tribological properties of carbon fiber‐reinforced thermoplastic polyimide composite

Polyacrylamideacrylate (PAN)‐based carbon fibers were submitted to nitric acid oxidation treatments to improve the interfacial adhesion of the carbon fiber (CF)‐reinforced polyimide (CF/PI) composite. The carbon fiber surfaces were characterized by X‐ray photoelectron spectroscopy (XPS). Nitric acid oxidation not only affects the oxygen concentration but also produces an appreciable change in the nature of the chemical functions, namely the conversion of hydroxy‐type oxygen into carboxyl functions. Nitric acid oxidation treatment modifies the element constituting the fiber, the nitrogen concentration being about 1.2 times higher at the fiber external surface compared to the untreated one. The mechanical and tribological properties of the polymide (PI) composites reinforced by the carbon fibers treated with nitric acid oxidation were investigated. Results showed that the tensile strength of the CF/PI composites improved remarkably due to nitric acid treatment along with enhancement in friction and wear performance. Copyright © 2009 John Wiley & Sons, Ltd.     

Structure–tribological property relationship of nanoparticles and short carbon fibers reinforced PEEK hybrid composites

In a previous work, the roles of low‐loading, that is, 1 vol %, nano‐SiO₂ particles on the tribological behavior of short carbon fibers (SCFs)/polytetrafluoroethylene (PTFE)/graphite filled polyetheretherketone (PEEK) were studied. In the present work, the effects of nanoparticle content, varying from 1 to 4 vol %, on the structure and the tribological performance of the composite was investigated. The polished cross sections of the composites were inspected using a scanning electron microscope (SEM). The incorporated nanoparticles significantly reduce the friction coefficients of the composite. With low pressure‐sliding velocity (pv) factors, nanoparticle agglomerates seem to exert an abrasive effect on SCF, and thereby lead to high wear rates. Under such conditions, an increase in nanoparticle content decreases the wear resistance. With high pv factors, the nanoparticles remarkably improve the wear resistance of the composite and the nanoparticle contents do not play an important role on the wear resistance. The worn surfaces, transfer films and wear debris of the composites were analyzed. The tribological mechanisms were discussed. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 801–811, 2010     

稀土元素表面处理对玻璃纤维填充金属—塑料多层复合材料冲击磨损性能的影响

金属 塑料多层复合材料由钢背、烧结多孔青铜中间层和聚四氟乙烯 (ＰＴＦＥ)与填料混合物组成的表层复合而成 ,具有金属和塑料原有的优良性能 ,如高的机械性能、低的热膨胀系数和低的摩擦系数、良好的导热性和优异的减磨性[1～ 3 ] 。众所周知 ,玻璃纤维可用来提高ＰＴＦＥ复合材料的力学性能[4～ 6 ] 。纤维与基体之间的界面结合力起着控制聚合物复合材料力学性能的重要作用 ,并主要受纤维表面处理的影响[7～ 9] 。Ｗａｔａｎａｂｅ[10 ] 认为只填充玻璃纤维的ＰＴＦＥ复合材料在水中的磨损大于其它复合材料 ,玻璃纤维易受磨损且细碎的玻…     

Mechanical Properties,Water Absorption,and Chemical Resistance of Napier Grass Fiber Strand–Reinforced Epoxy Resin Composites

Napier grass fiber strands were used as reinforcement to obtain composites with epoxy resin as matrix. To improve the surface, these fiber strands were treated with alkali solution. The composites were prepared by means of hand lay-up molding, then the effects of Napier grass fiber strand loading on mechanical properties such as tensile, flexural and impact, interfacial bonding, and chemical resistance were investigated. The composite with 20 wt.% Napier grass fiber strands gives excellent mechanical properties and chemical resistance, showing that it has the best bonding and adhesion of the composites. SEM micrographs of fractured and worn surfaces clearly demonstrate the interfacial adhesion between fiber and matrix. Alkali-treated Napier grass fiber strand–reinforced composites have better resistance to water and chemicals than the untreated fiber strand composites.     

Influence of Epoxy Resin Treatment on the Mechanical and Tribological Properties of Hemp-Fiber-Reinforced Plant-Derived Polyamide 1010 Biomass Composites

In this study, we investigated the influence of epoxy resin treatment on the mechanical and tribological properties of hemp fiber (HF)-reinforced plant-derived polyamide 1010 (PA1010) biomass composites. HFs were surface-treated using four types of surface treatment methods: (a) alkaline treatment using sodium chlorite (NaClO₂) solution, (b) surface treatment using epoxy resin (EP) solution after NaClO₂ alkaline treatment, (c) surface treatment using an ureidosilane coupling agent after NaClO₂ alkaline treatment (NaClO₂ + A-1160), and (d) surface treatment using epoxy resin solution after the (c) surface treatment (NaClO₂ + A-1160 + EP). The HF/PA1010 biomass composites were extruded using a twin-screw extruder and injection-molded. Their mechanical properties, such as tensile, bending, and dynamic mechanical properties, and tribological properties were evaluated by the ring-on-plate-type sliding wear test. The strength, modulus, specific wear rate, and limiting pv value of HF/PA1010 biomass composites improved with surface treatment using epoxy resin (NaClO₂ + A-1160 + EP). In particular, the bending modulus of NaClO₂ + A-1160 + EP improved by 48% more than that of NaClO₂, and the specific wear rate of NaClO₂ + A-1160 + EP was one-third that of NaClO₂. This may be attributed to the change in the internal microstructure of the composites, such as the interfacial interaction between HF and PA1010 and fiber dispersion. As a result, the mode of friction and wear mechanism of these biomass composites also changed.     

Chemical modification on UHMWPE microparticles to improve the interfacial and tribological properties of UHMWPE/carbon fabric/phenolic laminate in water environment

Carbon fabric (CF)/phenolic laminates filled with pristine and chromic acid treated ultra high molecular weight polyethylene (UHMWPE) microparticles were fabricated. Their interfacial and tribological properties in water environment were comparatively investigated. The interlaminar shear strength (ILSS) of the laminates was tested on a universal testing machine (DY35), and the tribological properties were evaluated by a block‐on‐ring tribo‐tester. The worn surfaces and the interfaces of the laminates were respectively analyzed by scanning electron microscope (SEM) and field emission SEM (FESEM). The change of the chemical composition of UHMWPE microparticles after chromic acid etching was analyzed by Fourier transform infrared spectroscopy (FTIR). The chemical state of carbon fiber surface was examined using X‐ray photoelectron spectroscopy (XPS). The results revealed that the chromic acid treated UHMWPE microparticles had more remarkable effect than the pristine ones on improving not only ILSS and wear resistance of CF/phenolic laminate, but also its immunity to water environment. This should be attributed to the strengthened interfaces in treated UHMWPE/CF/phenolic laminate, which were characterized by the drawn dendritic UHMWPE fibrils firmly clinging on the surfaces of carbon fibers and resin in a Boston ivy‐like manner. Copyright © 2015 John Wiley & Sons, Ltd.     

Interfacial studies on the ozone and air‐oxidation‐modified carbon fiber reinforced PEEK composites

In this work, ozone modification method and air‐oxidationwere used for the surface treatment of polyacrylonitrile(PAN)‐based carbon fiber. The surface characteristics of carbon fibers were characterized by XPS. The interfacial properties of carbon fiber‐reinforced (polyetheretherketone) PEEK (CF/PEEK) composites were investigated by means of the single fiber pull‐out tests. As a result, it was found that IFSS (interfacial shear strength) values of the composites with ozone‐treated carbon fiber are increased by 60% compared to that without treatment. XPS results show that ozone treatment increases the amount of carboxyl groups on carbon fiber surface, thus the interfacial adhesion between carbon fiber and PEEK matrix is effectively promoted. The effect of surface treatment of carbon fibers on the tribological properties of CF/PEEKcomposites was comparativelyinvestigated. Experimental results revealed that surface treatment can effectively improve the interfacial adhesion between carbon fiber and PEEK matrix. Thus the wear resistance was significantly improved. Copyright © 2009 John Wiley & Sons, Ltd.     

Effects of clay and surface plasma‐treated carbon fiber on wear behavior of thermoplastic POM composites

In engineering applications, experimental data and insight from scientific investigations on wear properties of polyoxymethylene (POM) composites are important for engineers to understand how to design and formulate POM materials with high resistance to wear. In this work, clay and carbon fiber were utilized and incorporated into POM and the mechanical and wear properties, in specific wear rate, were then assessed. The experimental results suggested that the addition of clay increased the tensile modulus and strength. The mechanical and wear properties of POM composites were found to improve with the addition of the carbon fiber. Carbon fiber/clay/POM composite exhibited the lowest specific wear rate and friction coefficient.     

The surface modification of carbon fiber for thermoplastic HDPE composites

The interfacial adhesion strength between the fiber and the matrix greatly affects the properties of the carbon fiber (CF)–reinforced composite. The presence of surface functional groups on the fiber and changes in surface roughness were determined by X-ray photoelectron spectroscopy, scanning electron microscopy (SEM), and Raman spectroscopy. The effect of surface modification of CF on the mechanical properties and tribological properties of the composites is enhanced. The performance has been significantly improved. SEM analysis showed that modification had a positive effect on the interface between fiber and matrix. In the paper, the method of CF modification and the treatment of enhanced high-density polyethylene have simple and effective characteristics, which can be widely used and have guiding significance for industrial production.     

Modification effects of short carbon fibers on mechanical properties and fretting wear behavior of UHMWPE composites

The present work comparatively studied the modification effects of short carbon fiber (CF) on the mechanical properties and fretting wear behavior of ultra‐high molecular weight polyethylene (UHMWPE)/CF composites. The interactions between CFs and UHMWPE interface were also investigated in detail. The results showed that, with the increase in fiber content, the compressive modulus and hardness of the composites increased, while its impact strength decreased. It was found that filling of CF can reduce the friction and wear of UHMWPE. In addition, the UHMWPE‐based composites reinforced with nitric acid‐treated CF exhibited better mechanical properties, lower friction coefficient, and higher wear resistance than those of untreated UHMWPE/CF composites. This was attributed to the improvement of interfacial adhesion and compatibility between CF and UHMWPE matrix caused by surface chemical modification of CF. Copyright © 2015 John Wiley & Sons, Ltd.     

Effect of solid lubricant particles on the tribological properties of PTFE composites lubricated with natural seawater

An orthogonal test was used to design different mixture ratios of molybdenum disulfide(MoS₂), graphite, and SiO₂ particles, which were filled with polytetrafluoroethylene (PTFE) composite. MoS₂-, graphite-, and SiO₂-modified PTFE was obtained by pressing and sintering, and the processing parameters were determined using progressive studies and experiments. The friction and wear properties of different PTFE composites lubricated with natural seawater were analyzed using an MMU-5G wear tester. A laser scanning confocal microscope was employed to examine the morphological characteristics of the worn surface. Moreover, the influence of particle proportions on the tribological property of composites was analyzed. Results show that the addition of SiO₂, MoS₂, and graphite can increase the bearing capacity, improve the wear resistance, reduce the friction coefficient, and increase the self-lubricating ability of the PTFE matrix.