文档介绍：硅酸盐学报· 2108 ·2009年气相二氧化硅/碳化硅复合绝热材料的制备与表征封金鹏1,倪文1,陈德平1,许为峰1,胡子君2,孙陈诚2(1. 北京科技大学土木与环境工程学院,北京 100083;2. 航天材料及工艺研究所,先进功能复合材料技术国防科技重点实验室,北京 100076) 摘要:采用碳化硅微粉作为红外遮光剂,通过干法成型工艺制备了具有优良高温绝热性能的气相二氧化硅/碳化硅复合绝热材料。利用场发射扫描电镜、热重–差热分析、导热系数测定等方法对复合材料的微观结构和热性能进行分析,研究了SiC粒度、添加量和复合材料密度对复合材料绝热性能的影响。结果表明:SiC的引入可明显降低红外辐射传热,有效提高材料高温绝热性能;当复合材料使用温度为500℃时,较适宜的SiC添加量为25%(质量分数),;此外,在满足材料力学性能要求的同时应尽可能降低其密度。关键词:气相二氧化硅;碳化硅;遮光剂;导热系数中图分类号:TB332 文献标志码:A 文章编号:0454–5648(2009)12–2108–04 PREPARATION AND CHARACTERIZATION OF FUMED SILICA/SiC THERMAL POSITES FENG Jinpeng1,NI Wen1,CHEN Deping1,XU Weifeng1,HU Zijun2,SUN Chencheng2(1. Civil & Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083; 2. National Key Laboratory of Advanced posite Materials, Aerospace Research Institute of Materials and Processing Technology, Beijing 100076, China) Abstract: Fumed silica/SiC thermal posites were essfully prepared. SiC was adopted as an opacifier to improve thermal insulating performance of posites at higher temperatures where the radiative heat transfer dominates. posites were characterized by using field emission scanning electron microscopy, thermogravimetric–differential thermal analysis and thermal conductivity measurement. The effects of particle size and content of SiC, and the bulk density of posites on thermal conduc-tivity of posites were investigated. Th