Crystallization Kinetics of Calcium Aluminate Glasses Studied by Non-isothermal Techniques  

作　　者：王衍行 ZU Chengkui HE Kun ZHAO Huifeng HAN Bin CHEN Jiang 

机构地区：[1]Institute of Quartz and Special Glasses,China Building Materials Academy

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2013年第5期907-911,共5页武汉理工大学学报（材料科学英文版）

基　　金：Funded by the National Natural Science Foundation of China(No.60808024)

摘　　要：The crystallization kinetics of 38.0CaO-38.0Al2O3-10.5BaO-6.5MgO-6.0Y2O3-1.0（Na2O＋K2O） （wt%） glass was studied by differential scanning calorimeter （DSC） and X-ray diffraction （XRD） techniques. Tile results showed that DSC curves of calcium aluminate glass have a single glass transition temperature followed by one crystallization peak for the heating rates β = 5 K/min and two crystallization temperatures T1 and T2 for β≥ 10 K/min. The activation energies of crystallization obtained from the Gao-Wang model of the first exothermal peak and the second exothermal peak of calcium aluminate glass are 340 and 662 kJ/mol, respectively. The Avrami exponents of the both crystallization peaks are approximately 2, indicating the two- dimensional crystalline growth during its transformation from amorphous to crystalline. Ca12Al14O33, Ca3Al2O6 and unknown crystalline phases firstly appear when calcium aluminate glass is heat-treated. With the extending of heat-treatment duration, BaAl2O4 phase comes out.The crystallization kinetics of 38.0CaO-38.0Al2O3-10.5BaO-6.5MgO-6.0Y2O3-1.0（Na2O＋K2O） （wt%） glass was studied by differential scanning calorimeter （DSC） and X-ray diffraction （XRD） techniques. Tile results showed that DSC curves of calcium aluminate glass have a single glass transition temperature followed by one crystallization peak for the heating rates β = 5 K/min and two crystallization temperatures T1 and T2 for β≥ 10 K/min. The activation energies of crystallization obtained from the Gao-Wang model of the first exothermal peak and the second exothermal peak of calcium aluminate glass are 340 and 662 kJ/mol, respectively. The Avrami exponents of the both crystallization peaks are approximately 2, indicating the two- dimensional crystalline growth during its transformation from amorphous to crystalline. Ca12Al14O33, Ca3Al2O6 and unknown crystalline phases firstly appear when calcium aluminate glass is heat-treated. With the extending of heat-treatment duration, BaAl2O4 phase comes out.

关 键 词：calcium aluminate glass GLASS-CERAMIC CRYSTALLIZATION CALORIMETRY 

分 类 号：TQ171.1[化学工程—玻璃工业]