NOL环层间剪切强度对T700S级干喷湿纺碳纤维湿法缠绕复合材料性能的影响

为研究影响碳纤维湿法缠绕复合材料性能的因素,通过国内外T700S级碳纤维表面状态、NOL环及φ150容器的性能试验,研究了NOL环层剪强度对T700S级干喷湿纺碳纤维湿法缠绕复合材料性能的影响。结果表明,T700S级干喷湿纺碳纤维φ150mm容器爆破性能与复合材料NOL环层剪强度相关,层剪强度越高,其φ150mm容器爆破性能越低。     

湿法缠绕成型T700碳纤维/氰酸酯树脂复合材料力学性能研究

研究了湿法缠绕成型的T700碳纤维/氰酸酯树脂复合材料NOL环及单向板力学性能。测试了树脂配方的粘度-温度特性,T700碳纤维/氰酸酯树脂复合材料NOL环的拉伸及剪切性能,采用SEM对NOL环拉伸试样破坏形貌进行了观察。测试了T700碳纤维/氰酸酯树脂单向板复合材料的常温拉伸性能、弯曲性能、层间剪切性能和高温弯曲性能。结果表明,树脂配方在25℃下的粘度为800 cps,可以直接在室温条件下用于复合材料湿法缠绕成型,并具有充分的使用期。NOL环的拉伸强度为2220 MPa,剪切强度为56. 8 MPa,树脂基体对碳纤维具有良好的浸润性,能够较好地发挥出碳纤维的高强度特性。T700碳纤维氰酸酯树脂单向板复合材料的高温力学性能优异,200℃下弯曲强度保留率高达60. 4%,250℃下弯曲强度保留率高达45. 0%。     

碳纤维湿法缠绕用高模量高韧性环氧树脂基体

设计了一系列针对碳纤维湿法缠绕的环氧树脂基体,测试了树脂浇注体及其复合材料的力学性能和热机械性能,研究了树脂基体对碳纤维复合材料界面性能的影响.试验结果表明,对韧性树脂体系,树脂基体的模量是发挥纤维强度的关键因素,模量的提升将大幅提高复合材料的综合性能.经复配和优化的树脂体系兼具高模量和高韧性,其T700碳纤维复合材料NOL环拉伸强度达到2480MPa,T800碳纤维复合材料NOL环拉伸强度达到2780MPa,玻璃化温度(Tg)超过200℃,具有优异的界面性能和耐热性能.     

基于NOL环的高性能纤维与环氧树脂的匹配性研究

纤维与树脂的界面对复合材料的整体力学性能有着显著的影响。基于NOL环的宏观力学测试一般被用来反映复合材料的界面粘结性能,因此适用于评价纤维与树脂之间的宏观力学性能匹配性。为了探究高性能碳纤维T700SC、T800HB及高强玻璃纤维与环氧树脂的宏观力学性能匹配性,本研究首先根据GB/T 1458—2008国家标准制备NOL环试样,再借助NOL环的拉伸和层间剪切强度测试分析了高性能纤维与环氧树脂不同匹配组合宏观力学性能差异的原因,并寻找出最佳匹配组合。结果表明:玻璃纤维与环氧树脂的界面存在最佳的粘结强度,而且不同粘结强度导致拉伸强度和破坏机理不同,而碳纤维复合材料界面性能较差,容易分层破坏;T800HB与环氧树脂的宏观力学匹配性优于T700SC,环氧树脂力学性能、碳纤维的表面微观结构与性质以及环氧树脂与碳纤维之间的相互作用关系是影响界面粘结性能的根本原因。该研究在高性能纤维单向复合材料的材料选择与设计方面具有现实意义。     

碳纤维／环氧树脂在橡胶内衬表面的全缠绕工艺设计

根据橡胶内衬碳纤维全缠绕压力气瓶的技术指标,依据网格理论对缠绕层和缠绕张力进行详细的理论设计计算,确定缠绕参数和工艺.选用的环氧树脂体系力学性能优异,其黏度满足缠绕成型工艺要求,同时复合材料NOL环的断面形貌表明该树脂体系与T800碳纤维界面结合良好.对缠绕成型的压力气瓶进行试验,检测表明.水压爆破试验和疲劳试验结果均满足复合材料气瓶的设计要求.     

活性碳纳米管对T700 CF/环氧树脂复合材料性能影响

本文通过对多壁碳纳米管进行酸化、酰氯化和氨基化处理,然后与活性稀释剂进行预反应,制备出了一种具有反应活性的碳纳米管。将0.5wt%的活性碳纳米管分散到环氧树脂中,通过湿法缠绕工艺制备出T700碳纤维/环氧树脂多尺度复合材料NOL环。实验结果表明,活性碳纳米管的加入能够显著降低树脂的表面能而对黏度影响不大;同时复合材料NOL环的拉伸强度、模量、断裂伸长率和层间剪切强度分别提高了8.9%、12.2%、1.8%和17.0%;树脂与纤维的界面黏结得到明显改善;复合材料玻璃化转变温度提高了16℃。     

M46J/BMP-316复合材料的成型工艺及其性能

针对耐高温的PMR-15型聚酰亚胺树脂BMP-316为基体材料、M46J碳纤维为增强材料的复合材料成型工艺，研究了它的亚胺化和固化工艺，尤其是固化过程中的压力控制；对M46J／BMP-316层合板和NOL环进行了常温和高温力学性能以及相关物理性能的测试；对碳纤维／聚酰亚胺复合材料M46J／BMP-316的性质作出一定的评价。     

国产T700碳纤维用环氧树脂及其复合材料性能研究

本文针对国产碳纤维特点研制一种新型改性环氧树脂配方,测试CCF700S碳纤维NOL环、单向板以及Ф150mm标准容器水压爆破,并对爆破后复合材料结合SEM对碳纤维的微观结构进行表征。试验结果表明,该改性环氧树脂体系与CCF700S碳纤维浸润性好,界面粘接能力强,力学性能优异,改性环氧树脂体系适用于CCF700S碳纤维湿法缠绕工艺。     

国产T800S级碳纤维表面特性对复合材料界面性能影响研究

对两种国产T800S级碳纤维与进口T800S碳纤维表面特性及其复合材料界面性能的关联性进行了研究。通过扫描电镜（SEM）与原子力显微镜（AFM）对三种碳纤维的表面形貌与粗糙度进行了表征;采用X射线光电子能谱（XPS）对三种碳纤维表面化学官能团比例进行了分峰计算;通过碳纤维表面静态接触角对纤维表面浸润性进行了分析。制备并表征了碳纤维NOL环与单向复合材料的力学性能与微观破坏形貌,通过对比分析确定了影响复合材料界面性能的关键性因素,对复合材料界面性能的进一步提升具有指导意义。     

碳纤维增强环氧改性氰酸酯树脂复合材料性能研究

分别采用热重分析(TGA)法、动态力学分析(DMA)法研究了碳纤维增强环氧改性氰酸酯树脂(CE/EP/CF)复合材料的热稳定性、耐热性及动态热力学性能,研究了此种复合材料强力环(NOL环)的力学性能。结果表明,CE/EP/CF复合材料具有优良的耐热性和热稳定性,玻璃化转变温度为226.33℃,NOL环层间剪切强度为48.7MPa。扫描电子显微镜(SEM)分析表明,CF与CE/EP树脂间的界面粘接良好。     

复合材料在城市建设中的应用

复合材料在城市建设中应用越来越广。简要介绍了桥梁防腐、碳纤维、玻璃纤维、涂料、胶粘剂、加气混凝土等在城市建设中的应用。     

Role of fibre–fibre and fibre–matrix adhesion in stress transfer in composites made from resin-impregnated paper sheets

Paper-reinforced plastics are gaining increased interest as packaging materials, where mechanical properties are of great importance. Strength and stress transfer in paper sheets are controlled by fibre–fibre bonds. In paper-reinforced plastics, where the sheet is impregnated with a polymer resin, other stress-transfer mechanisms may be more important. The influence of fibre–fibre bonds on the strength of paper-reinforced plastics was therefore investigated. Paper sheets with different degrees of fibre–fibre bonding were manufactured and used as reinforcement in a polymeric matrix. Image analysis tools were used to verify that the difference in the degree of fibre–fibre bonding had been preserved in the composite materials. Strength and stiffness of the composites were experimentally determined and showed no correlation to the degree of fibre–fibre bonding, in contrast to the behaviour of unimpregnated paper sheets. The degree of fibre–fibre bonding is therefore believed to have little importance in this type of material, where stress is mainly transferred through the fibre–matrix interface.     

非织造材料在汽车内饰中的应用

1非织造材料在汽车内饰中的应用 1．1汽车工业是纤维材料潜力巨大的市场 北美和欧洲汽车内饰材料市场将从2003年的170亿美元增加到2008年的220亿美元,主要内饰材料包括座椅、门内饰板、车厢地毯、车顶、仪表板、行李舱盖板以及吸音、隔热、隔振材料。     

Methodology for characterisation of glass fibre composite architecture

Abstract

The present study outlines a methodology for microstructural characterisation of fibre reinforced composites containing circular fibres. Digital micrographs of polished cross-sections are used as input to a numerical image processing tool that determines spatial mapping and radii detection of the fibres. The information is used for different analyses to investigate and characterise the fibre architecture. As an example, the methodology is applied to glass fibre reinforced composites with varying fibre contents. The different fibre volume fractions (FVFs) affect the number of contact points per fibre, the communal fibre distance and the local FVF. The fibre diameter distribution and packing pattern remain somewhat similar for the considered materials. The methodology is a step towards a better understanding of the composite microstructure and can be used to evaluate the interconnection between fibre architecture and composite properties.     

Development of novel silk/wool hybrid fibre polypropylene composites

Recycling and reusing fibrous waste is one of the most important environmental tasks that face the world, to reduce environmental loading and promote the most effective use of resources. In this study, the shuttle-less loom silk selvedge waste and wool fibres were used to produce functional composites. First, the silk selvedge waste was opened and converted into fibrous form. The opened silk fibres were mixed with wool and polypropylene staple fibres in the proportions of 35/15/50, 35/35/30 and 15/35/50. The functional composites were produced by compression moulding technique with optimum process conditions. The effect of silk and wool fibre content on the mechanical properties of silk/wool hybrid fibre polypropylene composites was studied by measuring the tensile strength, flexural strength and impact strength of the resultant composite material. The thermal conductivity and water uptake properties of the composites were also studied. The morphology of silk/wool hybrid fibre polypropylene composites was analyzed by scanning electron microscopy technique. It was found that the composite containing 35/15/50 silk/wool/polypropylene showed the best performance in mechanical properties. The tensile, flexural and impact strengths of 35/15/50 silk/wool/polypropylene composite sample were found to be 30.21 MPa, 19.88 MPa and 0.713 J, respectively. The results also showed that the thermal conductivity was the least while the silk and wool fibre contents were the most in the composite. The water absorption study showed that the composite containing more fibre content possessed maximum water uptake properties. The study strongly suggests that the silk/wool hybrid fibre polypropylene composite materials are quite capable of serving as a potential cost effective, technologically viable, and attractive substitute to the conventional glass epoxy composites used as electrical insulating materials in printed circuit boards.     

Mechanical Properties of Thermoplastic Butadiene–Styrene (SBS) and Oxidized Short Carbon Fibre Composites

This work reports on some results of research conducted on composite materials consisting of a butadiene–styrene (SBS) thermoplastic elastomer matrix filled with short carbon fibres previously subjected to oxidative treatment to increase the surface functionality. Scanning electron microscopy confirms the existence of interactions between the matrix and the fibre, which are not observed for commercial fibre fillers and which translate into mechanical strength increments, in terms of the Young’s modulus, tensile and tear strengths for the oxidized fibre composites. The stress–strain curves of the composites show yield point phenomena as strain is applied longitudinally to the main fibre orientation. In oxidized fibre composites the stress and strain coordinates are a function of the degree of oxidation (greater strain for more strongly oxidized fibre) and fibre strength (lower stress for longer treatment times). © 1997 SCI.     

Vegetable fibres in automotive interior components

This paper gives a brief status of the state of the art of the use of plastic/vegetable fibre composite materials for interior car parts and the technologies to realise such parts (injection moulding, low pressure injection moulding, thermoforming, thermocompression and co-injection moulding). The development activity on composite plastic-wood materials to be used in the automotive sector performed by J.C.A. is also presented, in particular the research lines performed on several kinds of vegetable fibres (eucalyptus, jute, flax, kenaf) to be applied on semi-finished products: granules (short vegetable fibre) for injection moulding, and extruded sheets (long and short vegetable fibre) for thermoforming.     

Stress distribution in carbon-post applied with different composite core materials: a three-dimensional finite element analysis

The aim of this study was to investigate, using three-dimensional finite element analysis [3D-FEA], the stress and/or strain distribution of five different resin composites used in combination with carbon fibre posts. FEA models of five different light-cured composites were employed. The stress distribution of composite in combination with carbon fibre post was analysed under two different loading conditions: (i) polymerization shrinkage and (ii) load of 150 N with a 35° tilt to the long axis of the tooth. The Material Fatigue Rate [MFR%] of composite materials, dentin and fibre post was calculated. The highest stress values were recorded for Heliomolar and Clearfil-Photo P. The lowest stresses and MFR% values were attained when using Diamond Crown. High MFR% value [>45%] for carbon posts were found in all the tested cases under load. Composite materials with a Young’s modulus similar to that of dentin should be selected for the restoration of endodontically-treated teeth when using carbon fibre posts. The peak of the polymerization stress of the composite core is localized at the ferrule level. This might induce an open margin with higher risk of coronal leakage.     

Thermophysical and Tribological Properties of Composite Materials Reinforced with Polyoxadiazole Fibres

The effect of the technology for manufacture of a composite material on the coefficient of linear thermal expansion is examined. The low- and high-temperature extrema of the dilatometric curve are found. The effect of physicochemical transformations both in the phenol—formaldehyde binder and in the Arselon reinforcing fibre is demonstrated. The important decrease in the friction coefficient of polymer composite materials with respect to steel in reinforcement with polyoxadiazole fibre in comparison to cotton fibre is demonstrated. __________ Translated from Khimicheskie Volokna, No. 3, pp. 50–53, May–June, 2005.