烧结工艺对合成莫来石晶相结构的影响

The influence of sintering technique on crystalline phases and microstructures of mullite synthesized

讨论不同烧结温度和保温时间对利用铝厂工业污泥与硅石为原料合成的莫来石材料晶相结构的影响.采用XRD和SEM表征各试样的晶相组成和显微结构.实验结果表明:污泥和硅石经高温煅烧各试样最多存在3Al2O3.2SiO2,Al2O3.SiO2和α-Al2O33种晶相,分析结果确定最佳烧成温度为1 480℃,保温时间为5 h,该条件的合成料中3Al2O3.2SiO2的含量达86.8%.

Mullite was successfully synthesized with waste aluminum slag and silicon rock. The influences of different sintering temperature and time on the crystalline structures were discussed. XRD and SEM techniques were used to characterize the crystalline phases. The results show that： three crystalline phases were formed at most in each specimen, they are： mullite（3Al2O·2SiO2 ） high - temperature stable phase, mullite （Al2O3·SlO2 ） with structure defect and α- Al2O3. The best sintering temperature was determined to be 1 480 ℃, the best sintering time was 5 h, under such conditions, the amount of 3Al2O3·2SiO2 is up to 86.8%.