Nucleation, crystallization behavior and microstructure of mica glass-ceramics in the system SrO ? 4MgO ? xAl_2O3 ? 6SiO_2 ? 2MgF_2 (x=l, 1.5 and 2)

摘要

The effect of varying Al_2O_3 content on the crystallization and microstructure behavior of strontium containing glasses based on the system SrO · 4MgO · Al_2O_3 · 6SiO_2· 2MgF_2 was investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The glass transition temperature (T_g) and first crystallization peak temperature (T_p~1) reduced with decrease in the alumina content. Glasses with x ≥ 1.5 exhibited a second crystallization peak temperature (T_p~2). The first crystallization peak temperature (T_p~1) corresponded to the formation of strontium fluorophlogopite and second crystallization peak temperature (T_p~2|) corresponded to the formation of strontium aluminum silicate.