TETRAGONAL TO ORTHORHOMBIC TRANSFORMATION DURING MULLITE FORMATION

被引：64

作者：

LI, DX ^{[1
]}

THOMSON, WJ ^{[1
]}

机构：

[1] WASHINGTON STATE UNIV,DEPT CHEM ENGN,PULLMAN,WA 99164

来源：

JOURNAL OF MATERIALS RESEARCH | 1991年 / 6卷 / 04期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1557/JMR.1991.0819

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The mullite formation process in both single phase and diphasic sol-gel precursors to mullite was studied using dynamic x-ray diffraction (DXRD). A metastable, tetragonal-like mullite phase was observed in all the single gels at temperatures from 980-degrees-C to 1200-degrees-C, but not in any of the other precursors. The tetragonal to orthorhombic mullite transformation was very slow as the lattice parameters, a and b, split and moved gradually away from each other as a result of a gradual decrease of alumina content in the mullite solid solution with increasing temperature from 1100-degrees-C to 1200-degrees-C. The formation of tetragonal mullite coincides with that of the Al-Si spinel. The occurrence of tetragonal mullite or the spinel (or both) is determined mainly by the processing conditions of the sol-gel precursors.

引用

页码：819 / 824

页数：6

共 28 条

[1] CELL DIMENSIONS, SOLID SOLUTION, POLYMORPHISM, AND IDENTIFICATION OF MULLITE AND SILLIMANITE [J].