钙长石基多孔陶瓷中莫来石晶须的原位合成机理与调控

项目名称： 钙长石基多孔陶瓷中莫来石晶须的原位合成机理与调控

项目编号： No.51472023

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 一般工业技术

项目作者： 李翠伟

作者单位： 北京交通大学

项目金额： 83万元

中文摘要： 低热导率-高气孔率-高强度之间的矛盾制约了多孔陶瓷在近空间高超声速飞行器用防/隔热关键部件的应用,申请者前期研究结果表明晶须增强是解决此矛盾的有效方法。在此结果启发下，本项目以原位合成莫来石晶须增强钙长石多孔陶瓷为研究对象，集中研究莫来石晶须的原位合成机理及调控机制。主要研究内容包括：确定关键工艺参数，制备结构可调的莫来石晶须增强钙长石多孔陶瓷；研究气孔率、气孔尺寸、孔径分布及钙长石基体结构对晶须合成过程的影响,揭示莫来石晶须的合成机理；研究晶须含量、长径比及与界面结合对热学、力学性能的影响规律；探究晶须增强多孔陶瓷的热力匹配规律，确定晶须调控机制。本项目旨在揭示多孔条件下晶须合成机理、晶须增强材料的热力匹配规律及晶须调控机制，从而解决低热导率-高气孔率-高强度之间的矛盾。本项目的开展，能取得创新性的成果，其成功实施对促进多孔陶瓷在近空间高超声速飞行器用防/隔热关键部件的应用具有指导意义。

中文关键词： 多孔陶瓷；晶须；钙长石；莫来石；热导率

英文摘要： Due to its good properties, porous ceramics is one of the best substitute materials which can be used as thermal insulator materials in near space hypersonic vehicle. But the contradiction among high strength, high porosity and low thermal conductivity restricts its application. A recent study indicates that it is an effective way to solve that problem by adding mullite whiskers into anothite porous ceramics. This project focuses on in-situ synthesis mechanism and control mechanism of mullite whisker. The main content includes: conforming key processing parameters to prepare in situ synthesized mullite whiskers reinforced anothite porous ceramics with tunable microstructure; investigating the effects of pososity, pore size, pore distribution and the microstructure of anorthite matrix on synthesis of mullite whisker and revealing its synthesis mechanism; researching the effects of mullite whisker content, aspect ratio and interface structure on thermal and mechanic properties; finding the law between thermal conductivity and strength; revealing control mechanism of mullite whisker. The purpose of this project is to reveal the in-situ synthesis and control mechanism of mullite whisker and to solve the contradiction among high strength, high porosity and low thermal conductivity. It is reasonable to believe that creative results can be achieved by performing this project. The present study is beneficial to promote the applications of anorthite based porous ceramics in near space hypersonic vehicle.

英文关键词： porous ceramics;whisker;anorthite;mullite;thermal conductivity