莫来石结合Al_2O_3-SiC浇注料的显微结构特征

Microstructure characteristic of mullite bonded Al_2O_3-SiC castable

借助SEM和EDAX研究了莫来石结合Al2O3 -SiC浇注料的显微结构特征。结果表明 :在莫来石结合Al2 O3 -SiC浇注料中 ,莫来石相与填充在其间隙的玻璃相形成连续基质 ;刚玉颗粒与基质中SiO2 反应生成的二次莫来石与基质中的原生莫来石交错存在 ,构成网状结构 ;SiC颗粒表面高温氧化生成的SiO2 膜 ,改善了SiC颗粒与基质的润湿性 ,是其与基质直接结合的媒介。

The microstructure of mullite bonded Al 2O 3-SiC refractory castable was studied by SEM and EDAX.In the mullite bonded Al 2O 3-SiC refractory castable,the continuous matrix are formed by the mullite phase and the glass phase that fills in the interstitions of mullite.The net structure is formed by the mullite in the matrix and the second mullite that is created by the alumina particles with SiO 2 in matrix.Silica film,formed by the oxidation of SiC at high temperature on the surface of SiC particles,improves the wetability between the SiC particle and the matrix and are the intermedium of the SiC particles directly bonded with the matrix.