外加颗粒增强金属基复合材料的现状及展望

综述了获得外加颗粒增强金属基复合材料(PMMC)的方法固态法和液态法,介绍了PMMC的最新技术及研究现状。     

颗粒增强金属基复合材料制备工艺评述

介绍了陶瓷颗粒增强金属基复合材料的进展状况，重点介绍了几种常用的制备方法，提出了一种新的制备工艺一块体分散法。指出了在制备技术中存在的主要问题及其解决方法。     

关于颗粒增强金属基复合材料的协同强化

复相材料的协同效应在其强度、韧性，断裂等特性和现象中表现得尤为明显，也是复相材料研究中认识最肤浅的内容。本研究通过对球形颗粒增强金属基复材料中模量强化与位位强化的分析，探讨了这两种强化间的协同作用。结果表明，该体系中协同强化作用是很明显的。一般通过适当的模型和数学处理，协同作者是可以逐步认识的。     

铸造金属基颗粒增强复合材料的研究现状与展望

铸造法是生产复合材料的主要方法之一。本文着重阐述了金属基颗粒增强复合材料的研究现状以及用各种铸造方法生产金属基颗粒增强复合材料的工艺，指出了生产过程中需要解决的一些主要问题，并展望了其应用前景。     

颗粒增强金属基复合材料热错配应力分析

基于弹塑性力学理论,分析了颗粒增强金属基复合材料在降温及升温循环过程中的热错酸应力,结果表明：降温期间复合材料基体发生了热错配塑性应变,升温期间则经历卸载过程;在升温期间存在一特定温度,此温度复合材料基体平均错配应力为零,在零应力温度下,热错配应力分布不均匀程度有所减小,零应力温度受复合材料冷却温度的影响,利用低温处理方法可以调整复合材料的零应力温度。     

SiCp增强金属基复合材料的研究进展

综述了SiCp增强金属基复合材料的国内外研究现状，着重介绍了SiCp增强金属基复合材料的制备、性能与应用前景。     

颗粒增强金属基复合材料的研究进展

介绍了颗粒增强金属基复合材料的发展现状及其分类与特点,着重介绍了铝基、镁基、钛基、铜基及镍基复合材料。综述了颗粒增强金属基复合材料的制备与成形技术;概述了粉末冶金法、多层喷射沉积法、搅拌铸造法、原位合成法以及挤压铸造法等工艺。最后提出了颗粒增强金属基复合材料存在的问题,指出了该复合材料将向组织均匀化、韧性化方向发展。     

颗粒增强金属基复合材料的研究进展

概述颗粒增强金属基复合材料的成型工艺,介绍各种工艺的制备过程、在制备技术中存在的主要问题及解决措施,列举典型制备工艺的优点及应用范围,介绍国内相关的研究成果和应用状况,并对其今后发展的方向进行了探讨。颗粒增强金属基复合材料具有成本低、高强度、高模量、高耐磨性、易于制造等优点。指出颗粒增强钢铁基复合材料是当前研究的重要方向之一,颗粒增强钢铁基复合材料具有广阔的应用前景。     

塑性加工对颗粒增强复合材料超塑性影响的研究

本文介绍通过塑性加工的形变方法，形变量，形变温度和形变速率等不同工艺途径获得颗粒增强铝基复合材料的超塑性。     

颗粒增强金属基复合材料国内专利分析

运用专利分析方法,对国内颗粒增强金属基复合材料的专利申请趋势、区域分布、主要专利权人、高产IPC及技术领域特征等进行分析,并剖析颗粒增强金属基复合材料的重要专利权人,识别该领域核心技术、重点技术发展趋势及开发应用情况,以期为掌握我国颗粒增强金属基复合材料产业发展趋势及驱动力,明确产业发展定位,识别未来市场产业需求提供有用的竞争信息。     

Effect of particle characteristics on deformation of particle reinforced metal matrix composites

The particle characteristics of 15% SiC particles reinforced metal matrix composites (MMC) made by powder metallurgy route were studied by using a statistical method. In the analysis, the approach for estimation of the characteristics of particles was presented. The study was carried out by using the mathematic software MATLAB to calculate the area and perimeter of each particle, in which the image processing technique was employed. Based on the calculations, the sizes and shape factors of each particle were investigated respectively. Additionally, the finite element model (FEM) was established on the basis of the actual microstructure. The contour plots of von Mises effective stress and strain in matrix and particles were presented in calculations for considering the influence of microstructure on the deformation behavior of MMC. Moreover, the contour maps of the maximum stress of particles and the maximum plastic strain of matrix in the vicinity of particles were introduced respectively.     

外加颗粒增强表层复合材料制备方法

按照采用热源和陶瓷增强颗粒的添加方式,对外加颗粒增强表层复合材料的制备方法分类.详细介绍了堆焊、激光熔覆、激光熔射、等离子熔化-注射等颗粒增强表层复合材料的制备方法,并分析了各种制备技术的优缺点.堆焊特点是基体与表层为冶金结合,效率高.激光熔覆可以实现输入的准确控制,冷却速度快,热畸变小.但是堆焊和激光熔覆过程都存在裂纹问题.激光熔射不受基体可焊性限制,可制备颗粒增强相连续分布的表层,避免裂纹的形成.等离子熔化-注射技术与激光熔射技术类似,可以制备出增强相体积分数从0～100%连续变化的梯度复合材料.避免由于增强颗粒分布不均引起的裂纹,实现低投入、低成本运行.     

Damage analysis for particle reinforced metal matrix composite by ultrasonic method

The damage characteristic of particle reinforced metal matrix composite （PMMC） was studied by ultrasonic non-destructive evaluation method. After the sample was damaged induced by tensile load, the ultrasonic wave that propagated in the sample were collected. The damage parameter was defined by ultrasonic parameter and the wave signals were analyzed by correlation method. The results show that with the increase of tensile load, the damage parameter increases and the correlation coefficient decreases. The fracture section morphologies of PMMC under tensile load were observed by SEM. It is found that there are many concaves in the metal matrix. Therefore the damage evolution can be concluded. The initial damage is induced by void nucleation, growth and subsequent coalescence in the matrix or interface separation.     

Cavitation-erosion mechanism of laser cladded SiC particle reinforced metal matrix composite

With 2 kW continuous wave Nd YAG laser, SiC ceramic powder was laser-cladded on the AA6061 alurniniurn alloy surface. Within the range of process parameters investigated, the parameters were optimized to produce the SiCk, reinforced metal matrix composites(MMC) modified layer on AA6061 alloy surface. After being treated, the modified layer is crack free, porosity-free, and has good metallurgical bond with the substrate. The microstructure and chemical composition of the modified layer were analyzed by such detection devices as scanning electronic microscope(SEM EDX) and X ray diffractometer(XRD). The performance of electrochemical corrosion and cavitation erosion and their mechanism were estimated by the microhardness tester, potentiostat and ultrasonicinduced cavitation device.     

Effect of particle cracking on the strength and ductility of Al-SiCp powder metallurgy metal matrix composites

The effects of particle cracking on the strength and ductility of Al-SiCp metal matrix composite material (MMC) was investigated. The composite was manufactured using a simple powder metallurgy (PM) technique of hot pressing followed by hot extrusion. Also, the effects of reinforcement weight fraction and strain rate variations on the strength and ductility of the same composite were examined. It was found that particle cracking plays a significant role in controlling the mechanical properties of the composite. It was shown that particle cracking is possible in an MMC material made with a low strength matrix (commercially pure aluminum), and increases with the increase of reinforcement weight fraction, applied strain rate, and amount of plastic deformation. The yield strength increases as a function of reinforcement weight fraction and to a lesser extent as the strain rate increases. The tensile strength increases at low SiCp weight fractions, then remains constant or decreases as more particles are added to the matrix.     

Effects of particle size on residual stresses of metal matrix composites

A finite element analysis was carried out on the development of residual stresses during the cooling process from the fabrication temperature in the SiCp reinforced AI matrix composites. In the simulation, the two-dimensional and random distribution multi-particle unit cell model and plane strain conditions were used. By incorporating the Taylor-based nonlocal plasticity theory, the effect of particle size on the nature, magnitude and distribution of residual stresses of the composites was studied. The magnitude thermal-stress-induced plastic deformation during cooling was also calculated. The results show similarities in the patterns of thermal residual stress and strain distributions for all ranges of particle size. However, they show differences in magnitude of thermal residual stress as a result of strain gradient effect. The average thermal residual stress increases with decreasing particle size, and the residual plastic strain decreases with decreasing particle size.     

Thermal residual stresses and stress distributions under tensile and compressive loadings of short fiber reinforced metal matrix composites

1　ＩＮＴＲＯＤＵＣＴＩＯＮＤｕｅｔｏｌａｒｇｅｒｄｉｆｆｅｒｅｎｃｅｉｎｔｈｅｒｍａｌｅｘｐａｎｓｉｏｎｃｏ ｅｆｆｉｃｉｅｎｔｂｅｔｗｅｅｎｔｈｅｆｉｂｅｒａｎｄｔｈｅｍａｔｒｉｘａｎｄｓｐｅｃｉａｌｇｅｏｍｅｔｒｉｃａｌｓｈａｐｅｏｆｔｈｅｆｉｂｅｒ ,ｔｈｅｔｈｅｒｍａｌｒｅｓｉｄｕａｌｓｔｒｅｓｓｅｓ (ＴＲＳ) ｇｅｎｅｒａｔｅｄｄｕｒｉｎｇｃｏｏｌｉｎｇｆｒｏｍｈｉｇｈ(ｐｒｏｃｅｓｓｉｎｇ)ｔｅｍｐｅｒａｔｕｒｅｔｏｒｏｏｍｔｅｍｐｅｒａｔｕｒｅｈａｖｅｉｍｐｏｒｔａｎｔｉｎｆｌｕｅｎｃｅ…     

Simplified prediction model for elastic modulus of particulate reinforced metal matrix composites

Some structural parameters of the metal matrix composite, including particulate shape and distribution do not influence the elastic modulus. A prediction model for the elastic modulus of particulate reinforced metal matrix Al composite was developed and improved. Expressions of rigidity and flexibility of the rule of mixing were proposed. A five-zone model for elasticity performance calculation of the composite was proposed. The five-zone model is thought to be able to reflect the effects of the MMC interface on elastic modulus of the composite. The model overcomes limitations of the currently-understood rigidity and flexibility of the rule of mixing. The original idea of a five-zone model is to propose particulate/interface interactive zone and matrix/interface interactive zone. By integrating organically with the law of mixing, the new model is found to be capable of predicting the engineering elastic constants of the MMC composite.     

Developments in the non-traditional machining of particle reinforced metal matrix composites

The non-traditional machining of particulate reinforced metal matrix composites is relatively new. However, researchers seem to pay more attention in this field recently as the traditional machining of particulate reinforced metal matrix composites is very complex. This research investigates different non-traditional machining, such as electro-discharge, laser beam, abrasive water jet, electro-chemical and electro-chemical discharge machining of this composite materials. The machining mechanism, material removal rate/machining speed and surface finish have been analysed for every machining process. This analysis clearly shows that vaporisation, melting, chemical dissolution and mechanical erosion are the main material removal mechanisms during non-traditional machining. The thermal degradation and the presence of reinforcement particles mainly damage the machined surface. The understanding of electro-discharge, laser beam and abrasive water jet machining is more developed than that of electro-chemical and electro-chemical discharge machining for particulate reinforced MMC.