Nucleation and crystallization kinetics of a multicomponent lithium disilicate glass by in situ and real-time synchrotron X-ray diffraction

摘要

In this study, the high-temperature phase transformation of a multicomponent lithium disilicate glass was investigated by in situ and real-time synchrotron X-ray diffraction in the SiO_2-Li _2O-P_2O_5-Al_2O_3-ZrO _2 glass system. Quantitative phase analysis via the Rietveld method was performed on the high-resolution data aiming to reveal the crystallization sequence, crystallization kinetics, and the role of P_2O_5 on nucleation. It is found that the nucleation of lithium metasilicate (LS) and lithium disilicate (LS_2) in this complex glass is triggered by the steep compositional gradients associated with the disordered lithium phosphate (LP) precursors in the glass matrix. The LS_2 crystals grow at the expense of the LS, cristobalite, and quartz phases in the glass during the isothermal crystallization process at 770 C. The nucleation kinetics is temperature dependent, and the induction period of nucleation is longer at a lower temperature.