关键词: MgO-Al2O3-SiO2系统;玻璃组成;分相;析晶

Abstract: The influences of compositions on phase-separation and crystallization of MgO-Al2O3-SiO2 system were discussed.Samples of different component points in every stage of thermal treatment were analysed by XRD、TEM and DTA.The results show that the higher MgO/Al2O3 and the higher SiO2 content in the composition,the more beneficial to produce phase-separation of MgO-Al2O3-SiO2 system.When MgO/Al2O3 is greater than 3 and SiO2 contentis more than 68mol％,the phase-separation can be observed in the quenching sample.When SiO2 content is high,it is easy to gather the liquid droplets together to form a interconnected worm-like second phase.With the decreasing of SiO2 content,the crystallization peaktemperature(Tp) of the glass gradually decreases,and the crystallization exothermic peak becomes sharp,the glass crystallization improves.The lower the SiO2 content and the higher MgO/Al2O3,the glass crystallization becomes easier.

Key words: MgO-Al2O3-SiO2 system;glass composition;phase-separation;crystallization