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碳/碳(C/C)复合材料是以碳为基体,碳纤维增强的复合材料,具有高比强度、高比模量、耐高温、耐腐蚀、耐疲劳、抗蠕变、导电、传热和膨胀系数小等一系列优异性能,既可作为结构材料承载重荷,又可作为功能材料发挥作用。同时,碳/碳(C/C)复合材料是一种能在超高温条件下工作的高温结构材料,所以在航空航天领域具有广阔的应用前景。本文综述了碳/碳(C/C)复合材料的制备相应力学、热学性能,化学性能和其在各领域的应用进展。 相似文献
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日本碳/碳复合材料的现状与进展 总被引:1,自引:0,他引:1
赵稼祥 《高科技纤维与应用》1998,23(1):23-25
本文从原材料、工艺、性能到应用,概述了日本有关研究机构对碳/碳复合材料的研究情况。 相似文献
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陶/碳材料自愈合抗氧化 总被引:1,自引:0,他引:1
碳材料以及碳/碳复合材料,是一种在高温下使用仍具有优良性能的结构材料。但是在高温下,如超过500℃,它却因易于被氧化而受到限制,仅能用于非氧存在的惰性环境之中。因此,人们对碳材料及碳/碳复合材料在高温下的抗氧化性保护产生了极大兴趣,并发现了具有较好保护性的硼硅酸盐玻璃。本文对此进行了研究,并对羊干、熔块对形成硼 硅酸盐的膜的影响作了实验。 相似文献
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详细地叔述了氧化碳/碳材料的制备、性能与应用。分析了抗氧化机制,指出,无论用硼酸盐浸渍还是用SiC涂层防氧化,其基本原理都是氧化后在碳/碳材料表面上形成一层完整的、致密的玻璃膜,这层膜抗挥发温度的高低就限定了它的使用温度。 相似文献
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介绍了化学气相沉积、原位热压、熔体浸渍、自蔓延高温合成等原位制备碳/陶复合材料的技术,展望了碳/陶复合材料的应用和发展前景。 相似文献
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采用不同表面宫能团的预氧化聚丙烯腈(PAN)纤维作为增强体,以酚醛树脂和煤沥青分别为基体材料制成的碳/碳复合材料已经开发出来了。树脂基复合材料的热解行为表现为:横截面收缩以及分别为18-24%和32-40%的重量损失,这取决于预氧化PAN纤维表面所含表面宫能团的数量。经1000℃热处理,树脂基复合材料的弹性强度和弹性模量分别在11.0-30MPa和30-50GPa范围内,而煤沥青基复合材料则在35-55MPa和30-50GPa范围内。经过石墨化(2700℃)处理后,树脂基复合材料的机械性能改变不大(复合物变脆),但煤沥青基复合材料的弱性强度则增加了4-6倍(200-250MPa),弹性模量增加2-3倍(100-120PGa)。因此,可利用预氧化PAN纤维作增强体来制备碳/碳复合材料,且与商业级碳纤维增强的碳/碳复合材料具有大致相同的机械性能(T-300,日本东丽制)。 相似文献
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碳/碳复合材料等温化学气相渗透工艺模糊系统建模 总被引:6,自引:1,他引:6
等温化学气相渗透(chemical vapor infiltration,CVI)是制备陶瓷基和碳基复合材料重要的传统工艺,该工艺主要的不足之处是周期极长,因此,优化工艺参数、提高沉积效率是目前等温CVI工艺研究的重点。在实验样本的基础上,利用遗传算法来自动获取和优化模糊规则,从而建立了碳/碳复合材料等温CVI工艺模糊系统。通过系统对训练样本和测试样本的输出,可以看出:系统具有较高的精度和泛化能力。利用该系统,得到了沉积温度、纤维体积分数和沉积室压强等参数对等温CVI工艺的影响规律,对实际生产中CVI工艺的制定有指导意义。 相似文献
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C16、C18混合脂肪酸中含有很多经济价值很高的组分,若能将这些组分分离出来加以利用,将极大地提高混合脂肪酸的利用价值,因此研究C16、C18混合脂肪酸的分离技术具有非常重要的意义。本文介绍了减压精馏、低温结晶、尿素包合、银离子络合、生物酶催化法等C16、C18混合脂肪酸分离方法在近十年来的研究进展,并分析了各种分离方法的优缺点和适用范围。减压精馏可以有效地将混合脂肪酸分离成C16组分与C18组分,但该法的主要问题是加热易使不饱和组分变质。尿素包合法最常用来分离C16、C18混合脂肪酸中的饱和组分与不饱和组分,目前对该法的研究主要集中在工艺条件的优化与改善。生物酶催化法选择性高、反应条件温和、绿色环保,目前已被用来分离α-亚麻酸以及γ-亚麻酸且效果良好。最后展望了C16、C18混合脂肪酸分离技术的发展前景,指出两种或多种分离方法组合以及生物酶催化法将是未来的发展趋势。 相似文献
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《Ceramics International》2022,48(16):22985-22993
In this study, C/C–SiC and C/C–SiC–ZrC composites were prepared via chemical vapor infiltration and polymer infiltration pyrolysis, and the ablation mechanism under hypersonic oxygen-rich environmental conditions was investigated. The C/C–SiC composites demonstrate an excellent ablation resistance in a hypersonic oxygen-rich environment with a relatively low temperature and speed of approximately 1800 K and 1100 m/s, respectively. It is only in the ablation center area with higher temperatures that a certain degree of thermochemical ablation was observed. The mass and linear ablation rates of C/C–SiC composites (0.027 g/s and 0.117 mm/s, respectively) showed a significant increase in a hypersonic oxygen-rich environment with a temperature and velocity of approximately 2050 K and 2000 m/s, respectively. The high-temperature ablation resistance of ZrC-modified C/C–SiC–ZrC composites improved significantly. However, the ZrC ceramic component had a considerable impact on the ablation resistance of the material. The structural integrity of C/C–20SiC–30ZrC composites was relatively high in hypersonic oxygen-rich environments with a jet temperature and velocity of 2050 K and 2000 m/s, respectively, and mass and linear ablation rates were 0.012 g/s and 0.015 mm/s, respectively. When the ZrC content increased by 40%, the ablation resistance of the composite reduced significantly, whereas the mass and linear ablation rates increased to 0.043 g/s and 0.130 mm/s, respectively. 相似文献
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Shraddha SinghV.K. Srivastava 《Ceramics International》2011,37(1):93-98
The electrical properties of carbon/carbon (C/C) and carbon/carbon-silicon carbide (C/C-SiC) ceramic composites were measured. The results show that the capacitance decreases rapidly with an increase in frequency and it becomes constant above a frequency of 500 kHz, whereas the dissipation factor increases with increasing frequency. C/C-SiC composites give higher value than C/C composites due to the presence of microcracks. 相似文献
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《Journal of the European Ceramic Society》2020,40(15):5120-5131
The objective of this paper is to determine the influence of the nature of the C/C/SiC composite on the oxidation rate of fibers and the interphase and the development of oxidation pathways using characterization techniques such as Xray micro-tomography (μCT), scanning electron microscope (SEM) and optical microscopy (OM). The microstructure of two C/C/SiC composites (named 2D-RMI and 2D-CVI) was characterized before and after ageing tests performed by Thermogravimetric Analysis (TGA) under dry air at 1000 °C and 1300 °C. The three techniques are complementary and tomography appears to be a promising means for monitoring the oxidation of parts in service. Moreover, the oxidation of a fiber does not develop in a parallel plan to the section but as conical shape. To calculate the oxidation kinetics related to the surface, it is therefore necessary to take into account the geometry of the fibers that offers a much more important reactive surface. 相似文献