连续纤维增强钛铝金属间化合物基复合材料的研究进展

综合论述了连续纤维增强钛铝金属间化合物基复合材料的进展情况,介绍了复合材料在发动机等航空航天领域应用的优势,总结归纳了基体的特性、常用纤维增强体、复合材料的力学性能、界面问题和制备技术.在此基础之上提出了今后的发展方向.     

颗粒增强Ti－Al化合物基复合材料

本文在介绍Ｔｉ－Ａｌ金属间化合物基体及其颗粒增强剂的基础上，重点讨论了利用ＸＤ合成法、自蔓延高温合成法及真空热压法制造ＴｉＢ２、ＳｉＣ、Ａｌ２Ｏ３、ＴｉＮｂ等颗粒增强Ｔｉ－Ａｌ金属间化合物基复合材料的力学性能，同时还对颗粒增强Ｔｉ－Ａｌ金属间化合物基复合材料的其它制造方法，如反应热压烧结法、冲击波固结法、高能高速法的工艺、特点也进行了简要叙述。     

Processing of Bamboo Fiber Reinforced Plastic Composites

Anatomical properties of bamboo fiber, like chemical constituents and ultra structure establish bamboo as superior to other known natural ligno-cellulosic fibers. Bamboo fibers have been separated and sized in the form of fibers and strips. These fibers and strips mat (in the form of orthogonal mat) have been used to reinforce epoxy and unsaturated polyester (USP) resins. A process has been developed to cast bamboo fiber reinforced plastic (BFRP) unidirectional, bidirectional and multidirectional composites. The resulting material combine the strength and resilience of bamboo fiber with dimensional stability and moisture resistance of thermosetting resin.     

连续纤维增强陶瓷基复合材料概述

八十年代以来 ,连续纤维增强陶瓷基复合材料以其优异的性能特别是高韧性 ,得到世界各国的极大关注和高度重视 ,并取得令人瞩目的发展。纤维增强陶瓷基复合材料已开始在航空、航天、国防等领域得到应用。本文从复合材料的增韧机制、制备方法、界面特性和界面改性以及应用等方面综述了国内外有关连续纤维增强陶瓷基复合材料的研究现状     

纤维增强CBT树脂基复合材料研究进展

介绍了环形对苯二甲酸丁二醇酯（CBT）的性能特点及其应用,综述了纤维增强CBT树脂基复合材料的国内外研究现状,包括制备工艺、力学性能以及应用等,并对其在复合材料领域的发展进行了总结与展望。     

电镀镍碳纤维增强铝基复合材料

提出一种碳纤维表面电镀镍的方法,通过正交实验优化了电镀镍配方及工艺条件,并研究了镀层的显微组织及镀液的成分、电流密度、电镀时间等工艺条件对沉镍速率和镀层质量的影响,并探讨了沉镍机理.用镀镍碳纤维制备铝基复合材料,观测碳纤维与铝的复合效果.     

A Novel Processing Technique for Tow Fiber Reinforced Metal Matrix Composites with Tailored Interfaces

A novel metal matrix composite processing technique based upon plasma-assisted physical vapor deposition (PVD) of metais/alloys has been developed wherein, starting with lower cost tow fibers, the tows are spread to separate the individual filaments and then each filament coated uniformly with the matrix by plasma sputtering inside a hollow cathode magnetron. The coated fibers are then densified into a composite. This technique allows the synthesis of metal matrix composites with high fiber volume fractions. The resulting composite exhibits a uniform microstructure with complete infiltration of the matrix. Further, the plasma-assisted deposition process spares the tow filaments from severe strength degradation normally associated with melt-infiltration processing. Also, for chemically or thermo-mechanically incompatible fiber-matrix systems, the technique allows the incorporation of an interfacial layer (engineered for greater chemical inertness or lower residual stresses) prior to the deposition of the matrix. This technique has been applied here to synthesize composites based on Nextel 610 tows and Superalloy matrices (Thermo-span, Haynes 214 or Inconel 718) with a Mo chemical barrier layer.     

Processing and Performance of Alumina Fiber Reinforced Alumina Composites

Processing of alumina fiber-reinforced alumina matrix composites by hot-pressing was described. The mechanical properties of the composites fabricated by different sintering conditions including temperature and pressure have been investigated. The results indicated that the higher sintering temperature and pressure corresponded to the higher bulk density and higher maximum strength of the composite, whereas the pseudo-ductility of the composite was lower. The preliminary results of the composite with monazite-coated fibers showed that maximum strength could be improved up to 35% compared with the noncoated fiber composite in the same sintering condition. Moreover, the fracture behavior of the composite changed from completely brittle fracture to non-brittle fracture under the suitable sintering conditions. SEM observation of the fracture surface indicated that the coating worked as a protective barrier and avoided sintering of the fibers together even at high temperature and pressure during densification process.     

碳纤维增强铜基复合材料摩擦与磨损行为的研究

研究了用热压法制造的碳纤维增强铜—5％锡基复合材料的摩擦磨损行为。对碳纤维的体积分数改变时,复合材料的摩擦系数,磨损速率的变化规律作了分析,进行了磨屑成分分析及磨面的形貌观察,初步提出了这种复合材料的磨损机制。实验结果表明:随着碳纤维含量的增加,复合材料的摩擦系数下降、磨损率减小,认为在给定的实验条件下,“碳纤维/铜—5％锡”复合材料的磨损是粘着和氧化共同作用的结果,在高温下或纤维体积含量较高时,氧化磨损是主要磨损形式。     

碳纤维增强铜基复合材料研究进展

本文综述了碳纤维在铜基复合材料中的作用及其表面处理技术的发展现状。总结了近年来碳纤维表面改性方法以及存在的主要问题,分析了碳纤维对铜基复合材料组织的形成及其性能的影响。最后展望了碳纤维的发展前景。     

Elastic Constants of Particle and Fiber Reinforced Metal Matrix Composites

Abstract

A model has been developed to predict the elastic moduli in composites reinforced with both particles and fibers. In the model the matrix material and the particles, which are assumed to be homogeneously distributed, form an effective matrix. The characteristics of this effective matrix is calculated using a theory formulated by Ledbetter and Datta. The effective matrix is then considered to be reinforced with fibers lying in one plane but randomly oriented in that plane. The effect of the 2-dimensionally random orientation of the fibers on the elastic moduli of the composites is determined in two steps. First the composite cylinders model by Hashin and Rosen for an aligned fiber system is employed, and then a geometric averaging procedure suggested by Christensen and Waals is performed. Using this model, the Young's and shear moduli were calculated for three samples with different aluminum matrices and volume fractions of particles (9, 13, and 17%) but the same fiber content (6%). The same elastic moduli were also determined using ultrasonic velocity measurements. The agreement between calculated and measured elastic moduli is found to be very good. Also, the elastic anisotropics between directions of the fiber rich plane and that normal to the plane could be predicted by the model.     

木纤维增强不饱和聚酯复合材料的性能研究

采用丙烯酸(AA)对木纤维表面进行改性处理,并对改性后的木纤维进行悬浮性测试。将改性处理后的木纤维与不饱和聚酯树脂复合,制备了木纤维增强不饱和聚酯复合材料,对其进行了拉伸和冲击等力学性能测试。结果表明:木纤维含量对复合材料的力学性能影响很大。随着木纤维含量的增加,复合材料的延伸率和拉伸强度均有所提高;当木纤维含量为15%时,改性处理试剂的最佳浓度为0.15mol/L。此时,材料的延伸率和拉伸强度增加的幅度均趋于平稳,力学性能变化不明显。     

连续纤维增韧陶瓷基复合材料的连接方法

连续纤维增韧陶瓷基复合材料(CMCs)在高温领域具有广阔的应用前景,但是由于其编织工艺的限制,难以制备十分精密和复杂的构件,而要使纤维增韧CMCs得到广泛的应用,必须解决复合材料与金属合金系列材料的连接问题.因而连接是CMCs走向工程应用需要解决的关键课题之一.综述了CMCs的连接现状,重点介绍了几种有效的连接CMCs的方法:钎焊、局部过渡液相连接、无压固相反应连接、聚合物分解连接、ARCJoinT、在线液相渗透连接等.     

Thermo-physical Properties of Continuous Carbon Fiber Reinforced Copper Matrix Composites

Continuous carbon fiber reinforced copper matrix composites with 70％(volume fraction)of carbon fibers prepared by squeeze casting technique have been used for investigation of the coefficient of thermal expansion(CTE)and thermal conductivity．Thermo-physical properties have been measured in both, longitudinal and transversal directions to the fiber orientation．The results showed that Cf／Cu composites may be a suitable candidate for heat sinks because of its good thermo-physical properties e．g．the low CTE(4.18×10-6／K)in longitudinal orientation and(14．98×10-6／K)in transversal orientation at the range of 20-50℃，a good thermal conductivity(87．2 W／m·K)in longitudinal orientation and(58．2 W／m·K)in transversal orientation．Measured CTE and thermal conductivity values are compared with those predicted by several well-known models．Eshelby model gave better results for prediction of the CTE and thermal conductivity of the unidirectional composites．     

碳纤维增强陶瓷基复合材料界面的研究进展

界面相作为复合材料基本组元之一,其结构组成与性能对材料的性能有着极其重要的影响.综述了碳纤维增强陶瓷基复合材料界面相的功能要求、界面结合类型.阐述了界面相厚度对复合材料性能的影响,适当的界面厚度有利于复合材料获得最佳性能.重点介绍了目前碳纤维表面涂层工艺的研究现状,并分析了各种制备工艺的优缺点.最后指出了今后碳纤维增强陶瓷基复合材料界面的研究方向.     

连续纤维补强增韧碳化硅基陶瓷复合材料研究进展

连续纤维补强增韧碳化硅基陶瓷复合材料具有密度低、强度和韧性高、抗氧化、耐高温等综合性能,已在国外宇航领域得到了广泛的应用.综述了国内外连续纤维补强增韧C/SiC陶瓷复合材料的研究进展,主要包括国内外在增韧机理、基体复合技术、界面技术以及应用等方面的研究进展情况.     

短碳纤维增强铝基复合材料孔隙率的研究

阐述了搅拌铸造制备短碳纤维增强铝基复合材料孔隙率的测定方法,分析了复合材料中形成孔隙的原因,试验从复合温度、搅拌桨形状、搅拌速度、保温时间和碳纤维加入量等条件入手,研究了影响搅拌铸造制备铝基复合材料孔隙率的关键因素.结果表明:复合温度控制在760℃、采用平面搅拌桨、搅拌速度为1200r/min、保温30min可有效降低复合材料的孔隙率,提高复合材料质量.     

碳纤维增韧陶瓷基复合材料界面的研究

综述了纤维增韧陶瓷基复合材料界面的研究现状，分析了现有的界面相的结构、界面结合类型和界面结合的机理，对碳纤维制备界面涂层方法进行了归纳总结，分析了目前碳纤维增韧陶瓷基复合材料界面材料的功能和要求，指出了今后碳纤维增韧陶瓷基复合材料界面材料发展的研究方向。     

表面镀Ni碳纤维增强Cu基复合材料的制备和表征

为提高碳纤维/铜(Cf/Cu)复合材料中Cf与Cu基体的结合强度,通过电化学法在Cf表面沉积一层约1μm厚的Ni镀层,进而沉积厚约6μm的Cu镀层,将镀覆Ni-Cu复合镀层的短纤维复合丝在800℃、20MPa下利用放电等离子烧结(SPS)制备镀镍碳纤维增强的铜基复合材料(Cf/Cu(Ni)),并与相同烧结工艺下制备的相同碳纤维体积分数的Cf/Cu复合材料进行对比。利用XRD和SEM分别研究了碳纤维表面Ni镀层的物相及表面形貌,用附带EDS的SEM研究了Cf与Ni-Cu复合镀层断面、Cf/Cu(Ni)复合材料表面及断口形貌,采用电子式万能试验机研究了未经修饰的碳纤维、镀Ni碳纤维、镀Cu碳纤维和Cf/Cu(Ni)以及Cf/Cu复合材料的拉伸性能。结果表明,镀Ni碳纤维复合丝的拉伸强度略高于未经修饰的碳纤维,断裂伸长率则略低于未经修饰的碳纤维,拉伸过程中Ni镀层无剥离,这与其表面Ni镀层和Cf的结合强度较高有关。Cf/Cu(Ni)复合材料呈塑性断裂,力学性能明显优于Cf/Cu复合材料,拉伸强度提高20%以上。     

Processing of Sisal Fiber Reinforced Composites by Resin Transfer Molding

In this paper, a linear flow model based on Darcy's law was used in the experiment to measure permeability of sisal textile. The Kozeny-Carman equation was employed to predict the permeability of sisal textile and the Kozeny constant was calculated through experimental results. Both experimental and predicted permeability values of sisal textiles were compared. Effects of fiber surface treatments and fiber volume fraction on the permeability of sisal textile were also studied in this research. Comparisons of mechanical properties of sisal-textile-reinforced composites manufactured by different processing technologies were made.