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碳纤维增强TiC复合材料的抗热震性能 总被引:1,自引:0,他引:1
通过测量力学性能和热物理性能,研究了热压烧结碳纤维增强TiC复合材料(Cf/TiC,20vo%碳纤维)的抗热震性能。结果表明,碳纤维加入到TiC基体中,提高了复合材料的抗弯强度和断裂韧性,降低了复合材料的弹性模量和热膨胀系数,进而使得复合材料的抗热震断裂参数R,抗热震损伤参数R^TV和裂纹稳定性参数RST都得以提高,复合材料热震残留强度在热震温差超过900℃后迅速下降。复合材料热扩散率的提高有利于抗热稳定性能的提高,复合材料增强机理是纤维承载。韧化机理是纤维桥联和纤维拔出。 相似文献
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采用扫描电子显微镜和X射线光电子能谱仪对经高温氧化处理的碳纤维表面的形貌和活性基团进行研究,并用处理过的纤维制成纤维增强复合材料试样,进行了强度试验及断口分析,同时讨论了氧化法提高纤维和树脂间界面结合强度的机制。 相似文献
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通过模拟方向舵带定位铆钉的铝合金梁与复合材料蒙皮之间的胶接试验,论述了复合与铝合金之间高温胶接后,试验件的变形形式及变形量,同时对定位铆钉的位置及数量对实验件变形的影响,以及铝合金热胀变形时对定位铆钉本身的影响进行了分析讨论。 相似文献
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使用CVD技术提高纤维增强陶瓷基复合材料的密度是很困难的,因为它很难使反应气体完全渗入到基体里面,这是由于“瓶颈”效应所致,即CVD过程阻塞了基体表面的小气孔,进而封闭了通向大气孔的入口,为此提出了一种新的方法位控CVD(PCCVD),来克服上述通过控制反应气体通道位置试样的加热位置,从而达到控制沉积位置,使沉积界面始终处于开孔状态,使用PCCVD技术制造的C/SiC复合材料,实际密度可达到其理论 相似文献
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碳纤维增强热塑性复合材料(CRTP)因其具有众多优点而在航空航天、轨道交通、国防军工和风力发电等领域受到广泛的关注。本文总结了近年来国内外关于CRTP制备技术的研究进展,主要从预浸料制备工艺、碳纤维(CF)表面改性技术及CRTP成型工艺3个方面进行阐述,并详细介绍了不同预浸料制备工艺、CF表面改性技术和CRTP成型工艺的优缺点及对所制备CRTP性能的影响;最后对预浸料制备工艺、CF表面改性技术和CRTP成型工艺的发展方向进行了展望。 相似文献
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Continuous nanoscale carbon fibers can be developed by stabilization and carbonization of highly aligned and extensively stretched electrospun polyacrylonitrile copolymer nanofiber precursor under optimal tension. These carbon fibers, with diameters of tens of nanometers, are expected to possess a superior mechanical strength that is unlikely to be achieved through conventional approaches. This is because i) the innovative precursor, with a fiber diameter approximately 100 times smaller than that of conventional counterparts, possesses an extremely high degree of macromolecular orientation and a significantly reduced amount of structural imperfections, and ii) the ultrasmall fiber diameter also effectively prevents the formation of structural inhomogeneity, particularly sheath/core structures during stabilization and carbonization. 相似文献
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采用搅拌摩擦加工技术制备不同含量多壁碳纳米管增强铝基复合材料,并对复合材料高温力学性能进行研究。结果表明:多壁碳纳米管的添加使得铝基体材料微观组织更加细小,并形成了少量纳米晶;铝基体中有较高密度位错,并在局部呈位错缠结状分布。与未添加多壁碳纳米管的铝基体相比,复合材料的高温拉伸强度明显增强,且随着碳纳米管含量的增加,复合材料强度逐渐提高,而高温塑性不断降低,350℃时,6.6%(体积分数)MWCNTs/Al复合材料的抗拉强度达到78MPa,为未添加多壁碳纳米管铝基材强度的3.9倍;断口分析表明,随着测试温度的提高,韧窝逐渐变小,呈脆性断裂特征。 相似文献
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S. W. Kim S. H. Lee J. S. Kang K. H. Kang 《International Journal of Thermophysics》2006,27(6):1873-1881
With restrictions for environmental protection being strengthened, thermoplastics reinforced with natural fibers such as jute, kenaf, flax, etc., have replaced automotive interior materials such as chemical plastics. In this study, the thermal conductivity of several kinds of thermoplastic composites in the form of board composed of 48.5 mass% polypropylene (PP) and 48.5 mass% natural fiber (NF), and reinforced with 3.0 mass% maleated polypropylene (MAPP) and 0.3 mass% silane as the coupling agents, were measured at temperatures of −10, 10, and 30°C, using a heat flow meter apparatus. The results show that the thermal conductivity is in the range of 0.05–0.07 W · m−1 · K−1, and the thermal conductivity increased about 10–15% by adding MAPP and about 10–25% by soaking in a silane aqueous solution. The tensile strength was also measured, and the result shows similar trends as the thermal conductivity.Paper presented at the Seventeenth European Conference on Thermophysical Properties, September 5–8, 2005, Bratislava, Slovak Republic. 相似文献
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Single Carbon Fibers with a Macroscopic‐Thickness, 3D Highly Porous Carbon Nanotube Coating 下载免费PDF全文
Mingchu Zou Wenqi Zhao Huaisheng Wu Hui Zhang Wenjing Xu Liusi Yang Shiting Wu Yunsong Wang Yijun Chen Lu Xu Anyuan Cao 《Advanced materials (Deerfield Beach, Fla.)》2018,30(13)
Carbon fiber (CF) grafted with a layer of carbon nanotubes (CNTs) plays an important role in composite materials and other fields; to date, the applications of CNTs@CF multiscale fibers are severely hindered by the limited amount of CNTs grafted on individual CFs and the weak interfacial binding force. Here, monolithic CNTs@CF fibers consisting of a 3D highly porous CNT sponge layer with macroscopic‐thickness (up to several millimeters), which is directly grown on a single CF, are fabricated. Mechanical tests reveal high sponge–CF interfacial strength owing to the presence of a thin transitional layer, which completely inhibits the CF slippage from the matrix upon fracture in CNTs@CF fiber–epoxy composites. The porous conductive CNTs@CF hybrid fibers also act as a template for introducing active materials (pseudopolymers and oxides), and a solid‐state fiber‐shaped supercapacitor and a fiber‐type lithium‐ion battery with high performances are demonstrated. These CNTs@CF fibers with macroscopic CNT layer thickness have many potential applications in areas such as hierarchically reinforced composites and flexible energy‐storage textiles. 相似文献
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利用快速通电加热技术,模拟针刺C/C复合材料的高温工作环境;运用双槽口剪切试验方法对材料在不同温度下的剪切强度进行研究;通过扫描电子显微镜观察试样断口形貌;采用红外测温技术测定了试样槽口及剪切截面温度。结果表明:材料剪切强度在一定范围内随温度升高而增加,1 800 ℃时剪切强度达到最大(35.6 MPa);针刺C/C复合材料室温下的主要破坏形式为纤维拔出及断裂,而高温下纤维与基体界面结合强度高,纤维拔出少,发生脆性断裂;随着温度升高,电流增大,槽口与剪切截面温差增大,较大的热应力及电流烧损使得材料在2 300 ℃时的剪切强度显著降低。 相似文献
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两种碳纤维增强Cf/BN-Si3N4复合材料性能对比 总被引:1,自引:0,他引:1
采用XRD,XPS和SEM对T300和T700两种碳纤维的物相结构、表面成分以及表面形貌进行了分析.分别以两种碳纤维编织件为增强体,采用先驱体浸渍一裂解(PIP)工艺制备了Cf/BN-Si3N4复合材料,并对其力学性能和微观结构进行分析.结果表明,两种碳纤维的石墨化程度、表面活性均相近,表面形貌差别很大.两种纤维增强的复合材料密度相当,但力学性能以及断裂行为有明显区别.与T300碳纤维增强的复合材料相比,T700增强的复合材料弯曲强度更高,弹性模量略低,具有更好的韧性.碳纤维表面状态的差异是纤维与基体的结合强弱以及复合材料力学性能不同的主要原因. 相似文献
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