TiO2对粉煤灰及石英砂制备微晶玻璃组织转变的影响

利用粉煤灰与石英砂制备微晶玻璃，并对其进行不同工艺的热处理．通过对热处理后的试样研究发现：当粉煤灰质量分数为30％，未加TiO2时，试样在780℃加热时首先析出过渡相Ca2SiO。，在随后的高温晶化过程中，过渡相溶解消失，析出更稳定的平衡相钙长石；当TiO2质量分数为0—15％时，随着TiO2含量的增加，在780℃加热时由析出梭形的Ca2SiO。微晶转变为析出粒状的钙长石微晶；当粉煤灰质量分数增加到40％，TiO2质量分数为3．5％时试样中出现网状微晶组织，而加入的形核剂TiO2质量分数达到5％时试样中无网状微晶组织出现，说明TiO2对网状组织的析出具有明显抑制作用．

Effects of TiO2 on the microstructure transformation of glass ceramics prepared by fly ash and quartz sand

Glass ceramics were prepared by fly ash and quartz sand,and subsequently heat treated with different processes.The glass ceramic specimens with different ingredients after heat treatment were investigated.When the mass fraction of ash fly is 30%,transitional phase Ca2SiO4 precipitates at first in the specimens without TiO2 during heating at 780 ℃,then it dissolves and disappears during crystallization at elevated temperatures,and finally the stable equilibrium phase of anorthite precipitates.When the mass fraction of TiO2 increases from 0 to 15%,the precipitates change from fusiform Ca2SiO4 microcrystals to granular anorthite microcrystals.When the mass fraction of fly ash increases to 40% and that of TiO2 is 3.5%,a reticular structure appears,and then it will vanish when the nucleation agent of TiO2 is added to 5%.It can be concluded that the precipitation of the reticular structure is restrained by TiO2.