利用高铝粉煤灰合成堇青石陶瓷材料的微观结构研究

Study on the microstructures of cordierite ceramics using high-alumina fly ash

以高铝粉煤灰、工业烧结镁砂及硅微粉为主要原料,按照堇青石的理论组成、以及富镁配方、缺镁配方、富铝配方和缺铝配方进行配比,并经120 MPa压力成型后在1280℃下进行烧成.实验结果表明:富镁配方的综合性能最佳,同时通过对烧结体进行XRD衍射和SEM扫描电镜微观结构分析,发现富镁配方的烧结体中含有大量六方晶系的α-堇青石和斜方晶系的β-堇青石,从而确定富镁配方为最佳配方.

High-alumina fly ash, industrial sintered magnesia and silica powder are used as main raw materials to prepare cordierite ceramic materials, based on stoichiometric ratio of cordierite composition and rich magnesium formula, poor magnesium formula, rich aluminum formula as well as poor aluminum formula, respectively. The above raw materials were mixed and molded under 120 MPa, and then were sintered at 1 280℃ to get the cordierite ceramics. XRD and Scanning electronic microscopy are carried out to investigate the phase composition and microstructure of cordierite ceramics. The results show that the rich magnesium formula processing is the best approach for preparation because crcordierite and （3-cordierite phases are both found in sintered compacts.