碳化硅颗粒增强铝基复合材料的航空航天应用

综合评述了近年来碳化硅颗粒增强铝基复合材料在航空航天领域所获得的一系列成功应用，并较为详尽地介绍了它们的具体应用情况以及对相关产品与装备所产生的积极作用。此外，还例举、分析和展望了该种复合材料在我国航空航天飞行器惯寻系统、光机结构及电子元器件中的几个颇具前景的应用方向。     

Machinability of Metal Matrix Composites Reinforced by 3-D Network Structure

Metal matrix composites reinforced by three-dimensional (3-D) continuous network structure reinforcement (3DCNRMMC) are difficult to machine due to serious tool wear and poor surface roughness caused by the brittle and hard reinforcement which interpenetrate into ductile matrix. In order to achieve the approach of low cost of 3DCNRMMC, the machinability of it needs to be understood. The influences of three cutting parameters and volume fraction of reinforcement on cutting force were analyzed in detail. The results indicate that: (1) Due to the brittle phase(s) introduced into ductile matrix of composites, there is a large fluctuation of cutting force causing deterioration of machinability. The fluctuation ranges of cutting forces, initially increase rapidly with the increase of volume fraction of reinforcement and then decrease finally, are largest at the range of the volume fraction of 55–65%; (2) The influence of cutting parameters on cutting force is obvious. With the increases of cutting speed, cutting force decreases gradually unless cutting speed exceeds the value of 209 m/min. Cutting forces increase with increasing feed rate and depth of cut; (3) Owing to the large fluctuation of cutting force, there were some cratered surfaces caused by Si₃N₄ reinforcement pulling-out and flaking-off. Some brittle phase protruding from the machined surface caused the deterioration of machined surface.     

纳米碳含量对碳/碳化硅陶瓷的机械加工性及与玻璃熔体润湿性的影响

采用无压烧结法制备纳米碳颗粒(nano-Cp)改性碳化硅陶瓷 (C_p/SiC), 研究了不同纳米碳含量对C_p/SiC陶瓷的机械加工性及与玻璃熔体润湿性的影响。通过XRD和SEM对C_p/SiC陶瓷进行物相和显微分析。研究结果表明: 随着可加工相纳米碳含量的增加, C_p/SiC陶瓷的机械加工性能得到明显改善。根据陶瓷材料的机械加工指数(M)综合评价, M₁₅=0.921＞M₂₅=0.547＞M₅=0.056＞M₀=0.021(下标数字代表碳含量), 且15wt%C_p/SiC中的碳颗粒预先被氧化, 抑制了C_p/SiC陶瓷基体表面形成SiO₂, 阻止了C_p/SiC陶瓷与玻璃熔体的润湿, 使夹具材料与玻璃熔体不发生粘接, 适合用作玻璃夹具材料。     

碳化硅纤维增强陶瓷基复合材料的研究进展

对碳化硅纤维（SiCf)增强陶瓷基复合材料（CMCS）的研究现状与进展作了较系统的论述。讨论了SiCf增强CMCS的界面层作用,热膨胀系数不匹配对材料的影响,高温抗蠕变抗疲劳性能及抗氧化性能等。最后指出了SiCf增强CMCS作为高温结构陶瓷材料的研究方向以及尚等解决的问题。     

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.     

碳化硅陶瓷及其复合材料的热等静压烧结研究

本文通过采用热等静压（ＨＩＰ）这一先进的烧结工艺，研究了Ａｌ２Ｏ３添加量对ＳｉＣ陶瓷之显微结构与力学性能的影响。并成功地制备出Ｓｉ３Ｎ４粒子以及ＳｉＣ晶须补强的ＳｉＣ基复合材料，结果表明：Ａｌ２Ｏ３是ＨＩＰ烧结ＳｉＣ陶瓷及其复合材料的有效添加剂，当添加３ｗｔ％Ａｌ２Ｏ３时，采用ＨＩＰ烧结工艺在１８５０℃温度和２００ＭＰａ压力下烧结１ｈ就可获得密度分别高达９７．３％、９９．４％和９７．０％的ＳｉＣ的     

不同颗粒度SiC增强铝基复合材料的切削加工性能与适用刀具

铝基复合材料中增强粒子的大小对复合材料的切削加工性能影响极大，本文研究了不同颗粒度碳化硅颗粒对铝基复合材料切削加工性能的影响。并分析了不同颗粒度碳化硅增强铝基复合材料所适用的刀具。探讨了切削刀具对不同大小颗粒碳化硅增强铝基复合材料的切削机理     

碳化硅颗粒增强Al基复合材料的新型制备工艺

综述了碳化硅增强铝基复合材料的几种主要制备工艺,重点阐述了高能超声半固态复合法制备SiCp/Al复合材料.首先用渗流法制备SiC体积分数高的SiCp/Al预制块,进行SiC预分散,然后将预制块加入处于半固态温度条件下的铝合金熔体中,最后导入超声波进行搅拌.此法很好地改善了增强颗粒与基体之间的润湿性,使SiC在基体中均匀...     

Aluminium matrix composites: Challenges and opportunities

Aluminium matrix composites (AMCs) refer to the class of light weight high performance aluminium centric material systems. The reinforcement in AMCs could be in the form of continuous/discontinuous fibres, whisker or particulates, in volume fractions ranging from a few percent to 70%. Properties of AMCs can be tailored to the demands of different industrial applications by suitable combinations of matrix, reinforcement and processing route. Presently several grades of AMCs are manufactured by different routes. Three decades of intensive research have provided a wealth of new scientific knowledge on the intrinsic and extrinsic effects of ceramic reinforcement vis-a-vis physical, mechanical, thermo-mechanical and tribological properties of AMCs. In the last few years, AMCs have been utilised in high-tech structural and functional applications including aerospace, defence, automotive, and thermal management areas, as well as in sports and recreation. It is interesting to note that research on particle-reinforced cast AMCs took root in India during the 70’s, attained industrial maturity in the developed world and is currently in the process of joining the mainstream of materials. This paper presents an overview of AMC material systems on aspects relating to processing, microstructure, properties and applications.     

On the Strength of Silicon Carbide Particulate Reinforced Aluminium Alloy Matrix Composites

In the present study, the modified continuum model, quench strengthening and dislocation pile-up model was respectively used to estimate the yield strength of SiCp/AI composites. The experimental results showed that the modified shear lag model or quench strengthening model would underestimate the yield strength of SiCp/AI composites. However, the modified Hall-Petch correlation on the basis of the dislocation pile-up model, expressed as σcy = 244 + 371λ-1/2, fitted very well with the experimental data, which indicated that the strength increase of SiCp/AI composites might be due to the direct blocking of dislocation motion by the particulate-matrix interface. Namely, the dislocation pile-up is the most possible strengthening mechanism for SiCp/AI composites.     

Effect of Graphene Nanoplate and Silicon Carbide Nanoparticle Reinforcement on Mechanical and Tribological Properties of Spark Plasma Sintered Magnesium Matrix Composites

Processing of magnesium （Mg） matrix composites reinforced with low reinforcement content （up to 4-5 vol.%） of graphene nanoplates （GNPs） and silicon carbide （SIC） nanoparticles using bait milling and spark plasma sintering （SPS） is reported. Near full densification was observed for all the composite compositions at the sintering temperature of 450 ~C （soaking time of 5 min and applied pressure of 50 MPa）. Detailed analysis of the microstructure and mechanical and tribological （under dry sliding contact with alumina counter-face） properties with reinforcement content in Mg-GNP and Mg-SiC is presented. Mg-GNP and Mg-SiC composites reinforced with about 2 vol.% of reinforcement content exhibited significant improvement in microhardness and wear resistance as compared with Mg compacts.     

石墨颗粒含量对(Grp+Al2O3-SiO2f)/ZL109混杂复合材料摩擦磨损性能的影响

利用挤压铸造法制备了硅酸铝短纤维(Al2O3-SiO2f)和石墨颗粒(Grp)混杂增强ZL109铝合金复合材料,并研究了石墨颗粒含量对该混杂复合材料摩擦磨损性能的影响规律.结果表明:石墨颗粒在混杂复合材料中可以起到明显的自润滑作用,特别在干摩擦高速磨损条件下其作用更为明显.当石墨颗粒含量超过5～8%时,混杂复合材料的摩擦系数保持在一个稳定的低值.无论在干摩擦还是在油润滑磨损条件下,单一硅酸铝短纤维增强复合材料的耐磨性较基体大幅度提高,而经石墨颗粒混杂后复合材料的耐磨性进一步提高,其含量在5～8%之间时其相对耐磨性取得最高值,而增强体更有利于复合材料干摩擦磨损性能的提高.     

Microstructure Development and Mechanical Properties of Ni Matrix/Carbide Composites

Nickel alloy matrix/dispersed carbide (VC, NbC, WC) composites were prepared by either flame-spray, liquid phase sintering, or solid state sintering. A commercial Ni-B-Si alloy was mixed with 15% vol. of carbide particles and used to prepare composite coatings by flame-spray, bulk composite materials by solid state sintering (below 1045^°C) or liquid phase sintering (above 1050^°C). Phase characterization was performed by X-ray diffraction, optical microscopy, scanning electron microscopy and X-ray fluorescence in energy and wavelength dispersive spectroscopy modes. Similar microstructural features were produced by thermal spray and liquid phase sintering: a Ni-rich matrix and a boron-rich intergranular phase. Sintered samples showed higher wear resistance than the coatings obtained by flame spraying. In both cases the wear mechanism is dominated by the plastic flow of the Ni-rich ductile matrix and the fracture of a boron-rich intergranular phase, the latter serving as a retainer. Carbide removal was observed for solid state sintered samples.     

基体各类对混杂复合材料摩擦磨损性能的影响

研究了基体种类对SiC和石墨（Gr)颗粒混杂增强铝基复合材料的摩擦磨损性能的影响。各种铝基体的混杂复合材料的耐磨性有明显差异,纯铝基混杂复合材料具有最好的耐磨性,其次是A356,2024和6061为基体的混杂复合材料。     

短碳纤维增强碳化硅基复合材料的制备与力学性能

利用注浆成型结合反应烧结的方法制备了高强度短碳纤维增强碳化硅基复合材料, 研究了分散剂(四甲基氢氧化铵)的含量和混料时间对浆料粘度的影响; 短碳纤维的体积分数、碳化硅粉的粒径对复合材料微观结构和力学性能的影响。结果表明, 添加0.1wt%的四甲基氢氧化铵得到的浆料粘度最低, 混料时间控制在6 h为佳。添加35vol%短碳纤维的复合材料的弯曲强度达到(412±47) MPa。由5 μm粒径碳化硅粉制备的复合材料的力学性能最佳, 其弯曲强度可达(387±40) MPa。将5与50 μm粒径的碳化硅粉进行2 : 1混合后得到的复合材料的力学性能优异, 弯曲强度可达(357±41) MPa。     

炭纤维针刺预制体增强C/SiC复合材料的制备与性能研究

以炭纤维复合网胎针刺织物为预制体, 采用“化学气相渗透法+先驱体浸渍裂解法”(CVI+PIP)混合工艺, 制备了C/SiC陶瓷复合材料; 研究了针刺预制体的致密化效率以及复合材料的微观结构和力学性能, 并与目前常用的三维编织C/SiC复合材料和预氧丝针刺织物增强C/SiC复合材料进行了对比. 结果表明, 针刺预制体的致密化效率明显高于三维编织预制体, 在相同致密工艺条件下, 炭纤维针刺织物增强复合材料和预氧丝针刺织物增强复合材料的密度分 别达到2.08和2.02g/cm³, 而三维编织预制体增强复合材料的密度仅为1.81g/cm³. 炭纤维针刺复合材料的力学性能高于预氧丝针刺复合材料, 弯曲强度和剪切强度分别达到237和26MPa.     

Cf/SiC复合材料的应用研究进展

Cf/SiC复合材料充分结合了碳纤维和SiC基体的优势,表现出低密度,高强度,高韧性,耐高温,耐烧蚀,抗冲刷,高硬度和高耐磨性等特点,成为航空航天、军事、能源等领域理想的高温结构材料.目前Cf/SiC复合材料已达到实用化水平,研究重点已转向应用研究.本文主要介绍Cf/SiC复合材料在热结构部件、热防护系统及高温光学部件等领域的研究进展.     

复合材料在传动过程中的摩擦磨损行为

采用化学气相渗透法(CVI)制备了二维碳纤维增强碳化硅(C/SiC)陶瓷基复合材料. 基于耦合应力等效模拟系统的开发, 采用摩擦扭矩的变化表征传动过程的摩擦磨损性能. 研究了以传动为背景的高载荷、低转速摩擦磨损行为及机理. C/SiC复合材料以其较低的摩擦扭矩、低的磨损率特别是在高载荷下的较小变形验证了良好的耐磨特性以及承载能力. 相同条件下其磨损率只有Ti合金的1/10～1/20. 低转速下磨损机理以磨粒磨损为主, 高载荷没有引起表面热裂纹.     

SiCp颗粒增强铝基复合材料塑性变形中过程的强化机制与断裂机制研究

综述了SiCp颗粒增强铝基复合材料的强化机制与断裂机制.分析了影响SiCp颗粒增强铝基复合材料强化、断裂的因素及其低塑性的原因,在此基础上提出改善其塑性的几点设想.