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传统的耐磨金属基复合材料普遍存在塑韧性低的问题。对氧化铝颗粒(Al2O3p)增强高锰钢复合材料进行球形网络构型设计,研究了构型方式、参数及热处理对复合材料压缩性能的影响。制备了3种构型参数(球径?分别为6 mm、7 mm、8 mm)结合两种构型方式(平行、错落)的Al2O3p/高锰钢球形网络复合材料、均匀复合材料和基体材料。结果表明:同构型方式下,随着构型参数(复合区体积分数)的增加,材料的压缩性能降低,其中?6材料的屈服强度、抗压强度和(抗压强度下)应变最佳,相比于均匀复合材料分别提升203.8%、236.1%和134.8%,屈服强度相比于基体材料提升107.5%;同构型参数下,错落排布比平行排布的屈服强度、抗压强度和应变分别提升10.9%、28.5%和16.3%;水韧处理后,错落排布材料的屈服强度降低35.2%,抗压强度提升11.0%,应变提升163.1%。裂纹易在基体区与复合区界面处萌生并进行扩展,基体能够阻碍裂纹的扩展;错落排布增大了复合区的最小间距,提升了塑性。 相似文献
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以碳纳米管、石墨烯为代表的超高性能纳米碳,具有优越的力、热、电等综合性能,是复合材料的理想增强体,以纳米碳为强化相少量加入到铝中,有望开发出高强、高模、低热膨胀的复合材料,并使复合材料保持轻质、易加工等特性,在航空、航天、国防等领域具有重大的应用前景,因而以纳米碳/铝为代表的新一代铝基复合材料备受关注。然而,碳纳米管等纳米碳易团聚,与铝等大多数金属并不浸润,且容易分布在晶界上诱导显著的晶粒细化,使得复合材料的强韧性等关键性能指标提升困难,或者使强度提高的同时使塑韧性下降显著,限制了其工程应用潜力。综述近年来国内外研究者在纳米碳/铝复合材料强韧化方面的策略和方法,包括纳米碳分散、界面和构型调控等,以期推动新一代轻质高强纳米碳/铝复合材料的发展,支撑国家未来重大工程应用。 相似文献
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高效热管理用金属基复合材料研究进展 总被引:1,自引:0,他引:1
从高导热复合构型、高导热复合界面及新型高导热纳米碳增强体3个方面,综述了热管理用铜基和铝基功能复合材料的研究进展,并对高导热金属基复合材料的未来发展方向进行了预测与展望.在材料组分相同的情况下,基于金属基体与导热增强体之间复合构型和复合界面的差异,制备的金属基复合材料的导热与热膨胀性能会发生显著变化.此外,由于纳米增强体与基体在形貌、尺寸及表面化学性质等方面的不相容性,在新型高导热金属基纳米复合材料的研发过程中,更需要兼顾高导热复合构型与复合界面的优化设计.可以预言,采用碳纳米管、石墨烯纳米片等新型纳米碳增强体,设计与制备具有微/纳米跨尺度分级复合构型的金属基复合材料将成为未来的研究热点. 相似文献
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石墨烯增强铜基复合材料的研究进展 总被引:1,自引:0,他引:1
综述了石墨烯/铜复合材料的球磨、液相混合和分子水平混合等制备方法及其力学、导电和导热等性能,总结了存在的主要问题;概述了层状仿生石墨烯/铜基复合材料的制备方法及性能,并展望了石墨烯/铜复合材料的研究方向及应用前景. 相似文献
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介绍了在先进复合材料的宏微观力学与强韧化设计领域内的国际发展趋势和国内发展状况、研究的科学意义、主要研究内容和面临的挑战、先进复合材料强韧化机制和原理、复合材料的宏微观力学理论与强韧化设计基本方法、存在的难点问题和发展方向。 相似文献
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Hot isostatic processing of metal matrix composites 总被引:1,自引:0,他引:1
The effect of four different Hot Isostatic Pressing (HIPping) treatments on porosity in the aluminium casting alloy A357 and stir-cast A357/15 vol% SiC particulate MMC has been investigated and the optimum treatment identified. The bend strength increased after HIPping relative to as-received. Such ceramic particle reinforced MMCs, however, do not have adequate toughness for many commercial applications. Metal reinforced MMCs made by combining an Al alloy matrix with stainless steel wire can provide a compromise between weight saving and toughness. The production, involving HIPping, of such a composite is discussed. 相似文献
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In an attempt to understand the cyclic deformation behavior of continuous fiber reinforced metal matrix composites, plastic strain controlled tests have been performed on tungsten monofilament-reinforced, multicrystalline, copper composites. The cyclic hardening response of the composites greatly depends on the fatigue dislocation structures corresponding to the strain amplitude. For example, at high strain amplitude, i.e. 1×10−3, secondary slip stimulated by the self-stresses of the primary dislocations becomes more active, and secondary hardening even occurs during saturation. At low strains, loop patches form and are associated with fine slip. At intermediate strains, persistent slip bands occur, but their distribution is altered by the presence of the fiber. The paper introduces a simple model to link the cyclic stress–strain response of the multicrystalline composites to those of monolithic single crystals and fibers. This model not only represents the fiber reinforcement by the rule of mixtures, but also adopts the Sachs model for the single crystal–polycrystal conversion factor. The results calculated by the model show very good agreement with the experimental data in all strain amplitudes at which the composites were fatigued. This encouraging outcome suggests that the new model could be applied to high-cycle fatigue of commercial continuous-fiber-reinforced polycrystalline metal matrix composites. 相似文献
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An analytical/computational fracture mechanics scheme, combined with finite element computations, is presented to explain observed fracture patterns in angle ply fiber-reinforced ceramic composite laminates. Unlike polymeric composites, where microcracks are channeled parallel to the fiber directions, cracks in ceramic composites initiate perpendicularly to the load axis. The results presented herein provide rational explanations for the experimental observations and confirm the advantages bestowed by multi-directional reinforcements. Such reinforcements would still allow the development of multitudes of matrix cracks, bridged by intact fibers, that lead to the desirable gradual and `graceful' failure of the composite. At the same time, multidirectional reinforcement prevents premature failures by constraining the laminate against interfacial fiber/matrix debondings. Such debondings, which may otherwise grow rapidly along the abovementioned weak interfaces, may readily occur in unidirectionally reinforced off-axis laminates, as noted in a preceding article. 相似文献
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High-speed turning experiments on metal matrix composites 总被引:3,自引:0,他引:3
The hard abrasive ceramic component which increases the mechanical characteristics of metal matrix composites (MMC) causes quick wear and premature tool failure in the machining operations. The aim of the paper is to compare the behaviour of high rake angle carbide tools with their diamond coated versions in high-speed machining of an Al2O3Al 6061 MMC. The influence of the cutting parameters, in particular cutting feed and speed, on tool wear and surface finish has been investigated. The higher abrasion resistance of the coatings results in increased tool life performances and different chip formation mechanisms. 相似文献
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Coating on reinforcements affects the interface bonding of a composite, and is therefore usually used for improving the composite's properties. The behaviour of SiC coating on carbon fibre in reinforced aluminium metal castings, Fe on carbon fibre-reinforced copper and alumina coating on K2O · 6TiO2 whisker-reinforced aluminium composites were investigated, respectively, by modern techniques such as TEM, SEM etc. with the goal of controlling the interfacial interaction and wettability of reinforcement with the matrices. SiC coating produced by a polycarbosilane solution process effectively improved the strength because it successfully controlled oxidation of the carbon fibres themselves and the harmful reaction between the carbon fibres and molten aluminium during the fabrication process and heating process of the composites. The metal coating, Fe, made by electrical plating, strengthened the bonding of carbon fibres with copper by changing the bonding state of the interface from a mechanical one to a partly chemical one. Therefore the strengths of the resulting composites were improved. The alumina coating on K2O · 6TiO2 also controlled the diffusion of the K element from the whiskers into the aluminium matrix and altered the reaction with aluminium, and led to the optimization of interfacial bonding between the whiskers and a superior composite. 相似文献