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。     

颗粒增强钛基复合材料的制备技术及微观组织

综述了近几年自生颗粒增强钛基复合材料的主要制备技术，其制备方法有粉末冶金、熔铸法、XD^TM法、燃烧合成法、燃烧合成-熔铸法、接触反应法、机械合金化法、激光熔覆法等。论述了不同制备方法中分别以碳化物和硼化物为增强相的钛基复合材料的微观组织。碳化物增强相主要有TiC，Ti2AlC，Ti3AlC等。硼化物增强相有TiB2和TiB。分别对增强相的形态进行了分析，并对钛基复合材料的发展提出了展望。     

钛颗粒增强镁基复合材料的制备方法

一种钛颗粒增强镁基复合材料的制备方法，步骤如下：选用钛颗粒以及镁或镁合金粉，镁粉或镁舍金粉体积百分比为70％-99％与钛粉1％～30％的体积百分比混合；将上述粉末连同玛瑙球按球料重量比3：1～4：1在球磨机上进行球磨，使之混合均匀；将混合均匀的粉末放入模具，在室温下压制成型；将压制的块体在真空炉中烧鲒；将烧结后的块体进行热挤压，挤压后冷加工制成零件或成品。     

自生颗粒增强铝基复合材料的制备工艺

采用原位反应工艺,通过在Al溶体中加入TiO,在一定温度下产生化学反应,反应生成Al3Ti颗粒,然后采用搅拌铸造法制备Al/Al3Ti复合材料,当TiO2加入量为20%～30%（质量分数）、反应温度为920℃时,铸态复合材料具有良好的力学性能。     

外加颗粒增强钢基复合材料的研究

采用离心铸造法获得了WC颗粒增强钢基复合材料环形件，其复合层厚度为15～18mm。分析表明：复合材料层的组织由大量的骨状的复式碳化物和针状马氏体基体组成；复合材料层中增强颗粒被高温钢液全部溶化，原位析出含W，Fe，Cr，Mo复式碳化物；基体合金被溶解的增强颗粒不同程度的合金化，复合层从外至内韧性升高、硬度降低，但梯度不大。     

颗粒增强金属基复合材料制备工艺的综述

概述了颗粒增强金属基复合材料的种类,介绍了目前颗粒增强金属基复合材料的常用的制备工艺.     

颗粒增强锌基复合材料研究现状与展望

颗粒增强锌基复合材料是当前研究较多、比较成熟、应用较广泛的金属基复合材料。综述了颗粒增强锌基复合材料的制备方法、界面微观结构、力学性能及摩擦磨损性能等的研究现状,分析了存在的技术难题,提出了今后的研究重点和发展方向。指出,喷射沉积快速凝固技术是继承传统铸造与粉末冶金发展起来的一种新型快速凝固技术,它将金属熔体的雾化和雾化液滴的沉积两个过程合为一体,直接由液态金属制备具有快速凝固组织特征的大块金属实体,是一种很有潜力的纳米颗粒增强锌基复合材料制备技术。     

颗粒增强镁基复合材料的制备工艺研究进展

综述了颗粒增强镁基复合材料的主要制备工艺和研究进展,重点介绍了粉末冶金法、搅拌铸造法和原位反应自生增强法等制备方法,并阐述了各种制备方法的特点和存在的问题。对颗粒增强镁基复合材料制备工艺的发展提出了自己的看法,指出半固态搅拌法是最适宜工业化生产的制备工艺,原位反应自生增强法是最具研究前景和发展潜力的制备工艺。     

颗粒增强铝基复合材料制备方法及其表面处理技术

颗粒增强铝基复合材料是当前研究比较多、比较成熟、应用较广泛的金属基复合材料。简要介绍了颗粒增强铝基复合材料的各种制备方法及应用现状，综述了该类复合材料表面处理技术的研究进展，确定了颗粒增强铝基复合材料化学镀镍工艺，测定了镀层的结合力和耐蚀性，结果表明所得镀层与基体结合良好，并且可以提高复合材料的耐蚀性。     

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。     

Review on preparation techniques of particle reinforced metal matrix composites

The need for new engineering materials with theadvancement of modern technology in the areas ofaerospace, automotive and numerous other industries haslead to a rapid development of metal matrix composites(MMCs) [1]. They can be tailored to have outstandingmechanical and physical properties such as high specificstrength and stiffness, good wear resistance, enhancedhigh-temperature performance, and better thermal andmechanical fatigue and creep-resistance than that ofmonolithic materials. Among…     

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.     

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.     

改善颗粒增强金属基复合材料塑性和韧性的途径与机制

评述了影响颗粒增强金属基复合材料塑性和韧性的各种因素,在此基础上深入研究了颗粒形状对ＳｉＣｐ／ＬＤ２复合材料塑性和断裂韧性的影响规律。采用有限单元法分析不同形状的ＳｉＣ颗粒增强的ＬＤ２复合材料的微区力学环境和整体力学行为,结果表明颗粒的尖锐化导致基体内应变集中和颗粒尖端断裂的可能性加剧,因而降低材料的塑性;而在外加载荷的作用下,由于复合材料基体整体均处于较高的加工硬化状态,因此颗粒形状对材料断裂韧     

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.     

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.     

Microstructures and wear resistance of large WC particles reinforced surface metal matrix composites produced by plasma melt injection

Large WC particles (− 840 μm-+ 420 μm) reinforced surface metal matrix composites (SMMCs) were produced using plasma melt injection (PMI) process on a Q235 (similar to ASTM A570 Gr. A) low carbon steel substrate. Microstructures of the SMMC were observed using scanning electron microscope (SEM), and the composition was determined with energy dispersion spectroscopy (EDS). Phases were analyzed with X-ray diffraction. Micro-hardness of the SMMC was tested. Wear losses of the SMMC layer were evaluated under dry friction conditions and compared with those of the substrate material. The results show that the large WC particles are caught by crystallized metal and stay in the upper part of the SMMC layer, and there is only a little melting on the outer surface. No sinking down of WC particles occurs. The SMMC layer is well bonded to the substrate, and the interface is crack free. The wear resistance of the Q235 substrate is greatly improved with large WC particles injected.     

离心铸造WC颗粒增强钢基复合材料辊环的研制

介绍了WCp/钢基复合材料轧辊的材料选择和制备工艺 ,并对其显微组织及力学性能进行了分析。工业实验结果表明 :复合材料轧辊的寿命比普通Cr12轧辊高 3倍以上     

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.