镧系稀土氯化物催化制备高强韧炭/炭复合材料基础研究

项目名称： 镧系稀土氯化物催化制备高强韧炭/炭复合材料基础研究

项目编号： No.51202233

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 无机非金属材料学科

项目作者： 邓海亮

作者单位： 中国航天科技集团公司第四研究院

项目金额： 25万元

中文摘要： 成本高、韧性差等问题限制了炭/炭复合材料的进一步发展与应用。稀土元素及其化合物具有独特的化学性能，作为催化剂已广泛用于烃类的裂解、芳构化和碳纳米管的制备，但国际上从未将其用于催化热解烃类制备炭/炭复合材料。我们的研究表明，预制体中添加氯化镧可大大缩短炭/炭复合材料的制备周期，并且其强度和韧性显著提高。基于此新发现，本项目提出采用镧系稀土氯化物催化热解二甲苯制备炭/炭复合材料，旨在明确稀土氯化物类型及其在预制体中的含量、沉积温度等对热解炭沉积动力学、基体显微结构、材料的力学、摩擦磨损及烧蚀性能的影响规律，获得强韧性高、摩擦磨损和烧蚀性能优异的低成本、高性能炭/炭复合材料及制备工艺。通过系统分析二甲苯热解的中间产物组分及终产物微观结构阐明热解炭的形成与沉积机理，并结合热解炭与纤维的界面结构研究揭示稀土化合物对炭/炭复合材料性能改善的内在作用机制，为深入挖掘炭/炭复合材料的性能潜力奠定理论基础。

中文关键词： 稀土；炭/炭复合材料；化学气相渗透；显微结构；力学性能

英文摘要： The further development and application of carbon/carbon (C/C) composites are limited due to the high cost and low toughness. Rare earth elements and their compounds have been used widely as catalysts in the decomposition and aromatization of hydrocarbons, and in the synthesis of carbon nanotubes, because rare earth elements have special chemical characteristics. However, no work is available on the application of rare earth elements or compounds in catalytic production of C/C composites. Our previous research shows that, as the content of lanthanum chloride in carbon fiber felts increases, the densifying time of C/C composites decreases, whereas the strength and the toughness of the composites increase obviously. In the present work, lanthanide chlorides are introduced into carbon fiber felts for catalytic production of C/C composites from xylene pyrolysis. The influences of lanthanide chloride's type and content, combined with deposition temperature, on the deposition kinetics and microstructure of pyrocarbon, as well as the mechanical, tribological and ablative properties of C/C composites are investigated. Subsequently, the composites with high strength and toughness, excellent tribological and ablative properties could be produced based on the optimization of densification parameters. Simultaneously, the fo

英文关键词： Rare earth；carbon/carbon composites；chemical vapor infiltration；microstructure；mechanical properties