利用煤矸石铁尾矿制备CaO-MgO-Al2O3-SiO2系微晶玻璃

为了综合利用固体废弃物，以煤矸石和铁尾矿为主要原料制备CaO-MgO-Al2O3-SiO2系微晶玻璃。利用DSC，XRD和SEM等分析测试手段，研究了核化和晶化温度对微晶玻璃析晶行为及显微形貌的影响，通过Kissinger方程计算了各基础玻璃试样析晶活化能E和动力学参数k(Tp)，并利用Augis-Bennett公式计算了各试样的晶化指数n。试验结果表明：随着核化和晶化温度的升高，主晶相衍射峰以先增强后减弱的趋势变化，主晶相为普通辉石(Ca(Mg，Al)(Si，Al)2O6)，体系的最佳晶化温度为1 040 ℃，其抗弯强度为216.49 MPa，耐酸性为99.21%；对于不同升温速率的基础微晶玻璃试样，20 ℃/min升温速率的析晶活化能最低为324.75 kJ/mol，k(Tp)=0.55，n=3.92，玻璃晶核为三维生长，整体结晶，4个试样的晶核生长方式相同。

Preparation of CaO-MgO-Al2O3-SiO2 glass-ceramic from coal gangue and iron ore tailings

In order to comprehensively utilize solid waste，the CaO-MgO-Al2O3-SiO2 glass ceramics were prepared from coal gangue and iron ore tailing.Effect of nucleation and crystallization temperature on crystallization behavior and microstructure of glass-ceramic samples were analyzed by DSC，XRD and SEM.The crystallization activation energy，E，and the crystallization kinetic parameter，k(Tp)，were calculated by employing the Kissinger equation.The avrami exponent，n，was calculated by the Augis-Bennett equation.The results show that as nucleation and crystallization temperature increases，the intensity of XRD peak increases first，and then decreases；the major crystalline phase of the glass-ceramics is augite (Ca(Mg，Al)(Si，Al)2O6)；the optimal crystallization temperature is 1 040 ℃，its flexural strength 216.49 MPa and acid corrosion 99.21%.For samples with different heating rates，the crystallization activation energy by a heating rate as 20 ℃ is the lowest with a value of 324.75 kJ/mol，the k(Tp) 0.55 and n 3.92.The glass nuclei is thoroughly grown in three-dimension.Also，four kinds of samples have the same way of crystallization.