Crystallization of CaO–MgO–Al2O3–SiO2 glass prepared by float process

Abstract

CaO–MgO–Al₂O₃–SiO₂ (CMAS) glass was prepared by float process. The effects of TiO₂ and heat-treatment on properties and crystallization behaviors of float glasses were investigated by atomic force microscope, differential scanning calorimeter, X-ray diffraction, electron probe microanalyzer, field emission scanning electron microscope and viscosity test. The results showed that CMAS parent glasses produced by float process had a high surface flatness (Ra is less than 80.1 ± 0.1 nm) and low tin penetration (14 μm). When the concentration of TiO₂ increased from 3.51 to 5.01 wt %, the glass transition temperature was decreased, and the crystallization temperature was shifted from 913 to 887°C using differential scanning calorimeter. Field emission scanning electron microscope images showed that phase separation was discovered in CMAS parent glass (containing 3.51 wt % TiO₂) treated at 670°C. Diopside as a major crystalline phase was precipitated in CMAS glass-ceramics nucleated at 700°C for 30 min and followed by crystallization at 910°C for 30 min.