氧化物陶瓷的多元系统中SiC晶须的原位合成及其机理研究

氧化物陶瓷（钾长石质瓷、锂质瓷、镁质瓷和钙质瓷）被广泛用作建筑陶瓷、日用陶瓷和工业陶瓷，与各行各业的发展息息相关。本项目针对各个材质的性能不足，拟在前期铝硅二元系统中原位合成SiC晶须的材料设计及研究基础上，耦合使用铝热还原碳化法、碳热还原法和直接合成法等技术方法，设计SiC晶须在不同材质的多元系统中原位合成的反应路线，在氧化物陶瓷中以原位合成的方式引入SiC晶须，旨在利用SiC晶须的高强、高韧和高热导率改善氧化物陶瓷的各项性能，获得SiC晶须改性陶瓷材料。本项目将系统地研究多元系统中SiC晶须的原位合成机理和生长过程，探讨助熔剂（K2O、Li2O、MgO和CaO）对晶须形貌和生长机制的影响，并通过调控原料共混物的熔融特性，对SiC晶须改性陶瓷材料进行致密化处理。最后，分析SiC晶须改性陶瓷材料的组成、结构和各项性能的相关性，揭示其内在规律，为SiC晶须在多元系统中的可控合成奠定科学基础。

Common oxide ceramics (i.e. potassium feldspathic ceramics, spodumene-based ceramics, magnesia ceramics, calcium-based ceramics) are comprehensively applied as building, domestic and industrial ceramics, which are highly related with the developments of various industries and trades. In this project, aiming at overcoming the weaknesses in the properties of different oxide ceramic matrix, SiC whiskers with excellent properties will be introduced into the matrix by in-situ synthesis method through the coupling uses of aluminium-assisted carbothermal reduction method, carbothermal reduction method and direct synthesis method, from which the technical routes for the in-situ synthesis of SiC whiskers in polynary systems are designed. Meanwhile, SiC whiskers toughed oxide ceramics will be obtained by improving the properties of oxide ceramic matrix with the assistance of SiC whiskers with high strength, high toughness and high thermal conductivity. The in-situ synthesis mechanism and the growth processes of SiC whiskers in the polynary systems during firing will be investigated systematically and the effects of flux oxides (i.e. K2O, Li2O, MgO and CaO) on the morphology and growth mechanism of SiC whiskers will be discussed. The densification of SiC whiskers toughed oxide ceramics will be conducted by adjusting the melting characteristics of ceramic blends. Finally, the relations among the phase compositions, microstructure and properties of SiC whiskers toughed ceramics will be analyzed, in which the inherent laws can be revealed. This project will establish a solid scientific foundation for the controllable preparation of SiC whiskers in the polynary systems of oxide ceramics.